MicroRNA-31-3p Expression is a Predictive Biomarker of Anti-EGFR Efficacy in Patients with RAS Wild-type Metastatic Colorectal Cancer

SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 140,250 new cases of CRC will be diagnosed in the United States in 2018 and about 50,630 patients are expected to die of the disease. The lifetime risk of developing CRC is about 1 in 21 (4.7%). Advanced colon cancer is often incurable and standard chemotherapy when combined with anti EGFR (Epidermal Growth Factor Receptor) targeted monoclonal antibodies such as VECTIBIX® (Panitumumab) and ERBITUX® (Cetuximab) as well as anti VEGF agent AVASTIN® (Bevacizumab), have demonstrated improvement in Progression Free Survival (PFS) and Overall Survival (OS). The benefit with anti EGFR agents however is only demonstrable in patients with metastatic CRC, whose tumors do not harbor KRAS mutations in codons 12 and 13 of exon 2 (KRAS Wild Type). It is now also clear that even among the KRAS Wild Type patients, about 15-20% have other rare mutations such as NRAS and BRAF mutations, which confer resistance to anti EGFR agents.

MicroRNAs (MiRNA) are small non-coding RNA molecules that play a key role in the regulation of intracellular processes through post-transcriptional regulation of gene expression. It has been shown that MicroRNAs controlling expression of oncogenes and tumor suppressor genes are frequently deregulated in cancer cells. One MiRNA which is frequently deregulated in a variety of cancers is MiR-31, which is frequently overexpressed in colorectal cancer, with high expression correlating with advanced disease. A mature sequence of MiR-31, MiR-31-3p, has been shown to predict outcomes among for colorectal cancer patients treated with anti-EGFR therapy such as ERBITUX® and VECTIBIX®.

FIRE-3 is an open-label, randomized Phase III trial in which FOLFIRI plus ERBITUX® was compared with FOLFIRI plus AVASTIN®, as first line treatment in patients with metastatic ColoRectal Cancer (CRC). This study suggested that patients with KRAS exon 2 wild-type metastatic CRC had a longer Overall Survival (OS) when treated with FOLFIRI plus ERBITUX® compared with FOLFIRI plus AVASTIN®.

Based on the premise that MiR-31-3p expression has been shown to be associated with response to anti-EGFR therapy, in previously published studies, the authors investigated the predictive role of this biomarker in the FIRE-3 study patient population, in its ability to differentiate outcomes between patients receiving anti-EGFR and anti-VEGF therapy. In this study, MiR-31-3p expression was measured in primary tumors obtained from 340 RAS wild-type mCRC patients enrolled in the FIRE-3 Trial. The study population included 164 patients randomized to receive FOLFIRI plus ERBITUX® and 176 patients to FOLFIRI plus AVASTIN®. Patients were divided into subgroups, defined by Low or High MiR-31-3p expression.

It was noted that patients with Low MiR-31-3p expression benefited from ERBITUX® combination compared to AVASTIN® for PFS (HR=0.74;P=0.05), OS (HR=0.61;P<0.01) and Objective Response Rate (P<0.01). There was however no difference in outcomes among High MiR-31-3p expressors between the two treatment groups.

It was concluded that MiR-31-3p expression level is a validated predictive biomarker of anti EGFR therapy efficacy for RAS wild-type mCRC patients, and can enable clinicians to identify patients who would benefit from first-line anti-EGFR treatment. MiRNAs are well preserved in Formalin-Fixed Paraffin-Embedded (FFPE) tissues and MiR-31- 3p expression levels can be measured using RT qPCR. Validation of miR-31-3p Expression to Predict Cetuximab Efficacy When Used as First-Line Treatment in RAS Wild-Type Metastatic Colorectal Cancer. Laurent-Puig P, Grisoni ML, Heinemann V, et al. Clin Cancer Res. 2018 Aug 14. pii: clincanres.1324.2018. doi: 10.1158/1078-0432.CCR-18-1324. [Epub ahead of print]

Dual Inhibition Improves Outcomes for Patients with BRAF-Mutated Colorectal Tumors

Dual Inhibition Improves Outcomes for Patients with BRAF-Mutated Colorectal Tumors
SUMMARY: ColoRectal Cancer (CRC) is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society estimates that approximately 135,430 new cases of ColoRectal Cancer will be diagnosed in the United States in 2017 and over 50,260 patients are expected to die of the disease. The DNA MisMatchRepair (MMR) system is responsible for molecular surveillance and works as an editing tool that identifies errors within the microsatellite regions of DNA and removes them. Defective MMR system leads to MSI (Micro Satellite Instability) and hypermutation, triggering an enhanced antitumor immune response. MSI (Micro Satellite Instability) is therefore a hallmark of defective/deficient DNA MisMatchRepair (MMR) system and occurs in 15% of all colorectal cancers. Defective MisMatchRepair can be a sporadic or heritable event. Approximately 65% of the MSI tumors are sporadic and MSI-High tumors tend to have better outcomes. Patients with stage IV colorectal cancer are now routinely analyzed for extended RAS and BRAF mutations. KRAS mutations are predictive of resistance to Epidermal Growth Factor Receptor (EGFR) targeted therapy. Approximately 5-10% of all metastatic CRC tumors present with BRAF V600 mutations and BRAF V600 is recognized as a marker of poor prognosis in this patient group. These patients tend to have aggressive disease with a higher rate of peritoneal metastasis and do not respond well to standard treatment intervention. Approximately 25% of the BRAF-mutated population in the metastatic setting has MSI-High tumors, but MSI-High status does not confer protection to this patient group.BRAF-and-EGFR-Inhibition-in-MAPK-Pathway
The Mitogen-Activated Protein Kinase pathway (MAPK pathway) is an important signaling pathway which enables the cell to respond to external stimuli. This pathway plays a dual role, regulating cytokine production and participating in cytokine dependent signaling cascade. The MAPK pathway of interest is the RAS-RAF-MEK-ERK pathway. The RAF family of kinases includes ARAF, BRAF and CRAF signaling molecules.BRAF is a very important intermediary of the RAS-RAF-MEK-ERK pathway. The BRAF V600 mutations results in constitutive activation of the MAP kinase pathway. Inhibiting BRAF can transiently reduce MAP kinase signaling. However, this can result in feedback upregulation of EGFR signaling pathway, which can then reactivate the MAP kinase pathway. This aberrant signaling can be blocked by dual inhibition of both BRAF and EGFR.
ZELBORAF® (Vemurafenib), is a selective oral inhibitor of mutated BRAF whereas ERBITUX® (Cetuximab) is a monoclonal antibody targeting Epidermal Growth Factor Receptor (EGFR). Preclinical studies have shown that adding CAMPTOSAR® (Irinotecan) to ZELBORAF® and ERBITUX®, in patients with refractory BRAF V600E metastatic CRC, led to a durable responses and this combination was safe and tolerable. However, both single agent ZELBORAF® and ERBITUX® were shown to have limited activity in this patient group.
Based on this scientific rationale, a phase II trial was conducted (SWOG 1406), in which 106 metastatic ColoRectal Cancer patients, with mutations in BRAF V600 and extended RAS wild-type, were enrolled. Patients were randomized to receive CAMPTOSAR® 180 mg/m2 IV every 14 days and ERBITUX® 500 mg/m2 IV every 14 days, with or without ZELBORAF® 960 mg orally twice daily. The median age was 62 years and about 50% of patients had received 1 prior regimen for metastatic or locally advanced unresectable metastatic CRC, and 39% had received prior treatment with CAMPTOSAR® . Prior therapy with anti-EGFR agent or RAF or MEK inhibitors was not allowed. Crossover from the control arm to the experimental group was allowed, after documented disease progression. The primary endpoint was Progression Free Survival.
The median Progression Free Survival was 4.4 months with the triplet, versus 2.0 months with CAMPTOSAR® plus ERBITUX® (HR=0.42; P =0.0002). The response rate was 16% versus 4%, and the Disease Control Rate was 67% versus 22% (P =0.001), with a higher Duration of Response with the addition of ZELBORAF® to CAMPTOSAR® and ERBITUX® (Triplet). Approximately 50% of the patients in the control group crossed over to the experimental group at the time of disease progression. Overall Survival data and efficacy at cross-over, data, remain immature. Patients in the experimental group (Triplet group) experienced more grade 3/4 toxicities such as neutropenia, anemia and nausea, and this increase was attributed to increased duration of exposure to therapy.
The authors concluded that the addition of ZELBORAF® to the combination of CAMPTOSAR® and ERBITUX® resulted in a 58% reduction in the risk of disease progression and a higher Disease Control Rate, suggesting that simultaneous EGFR and BRAF inhibition (Dual Inhibition) is effective in BRAF V600 mutated ColoRectal Cancer. Subgroup analysis will examine the role of CAMPTOSAR® pre-treatment and the outcomes of patients based on tumor MicroSatellite Instability. Randomized trial of irinotecan and cetuximab with or without vemurafenib in BRAF-mutant metastatic colorectal cancer (SWOG 1406). Kopetz S, McDonough SL, Morris VK, et al. J Clin Oncol 35, 2017 (suppl 4S; abstract 520)

XARELTO® in Cancer Patients Associated with Fewer Episodes of VTE Compared with FRAGMIN® but Increase in Nonmajor Bleeding

SUMMARY: The Center for Disease Control and Prevention (CDC) estimates that approximately 1-2 per 1000 individuals develop Deep Vein Thrombosis (DVT)/Pulmonary Embolism (PE) each year in the United States, resulting in 60,000-100,000 deaths. Venous ThromboEmbolism (VTE) is the third leading cause of cardiovascular mortality, after myocardial infarction and stroke.

Approximately 20% of cancer patients develop VTE and there is a two-fold increase in the risk of recurrent thrombosis in patients with cancer, compared with those without cancer. The current recommendations are treatment with parenteral Low Molecular Weight Heparin (LMWH) preparations for at least 6 months or probably longer, as long as the cancer is active. This however can be inconvenient and expensive, leading to premature discontinuation of treatment. LMWH accelerates the inhibition by Antithrombin of activated Factor X, in the conversion of Prothrombin to Thrombin. Direct Oral AntiCoagulants (DOACs) have been proven to be noninferior to COUMADIN® (Warfarin), a Vitamin K antagonist, for the treatment of acute VTE, and are associated with less frequent and less severe bleeding and fewer drug interactions. However, the efficacy and safety of DOACs for the treatment of cancer-associated VTE have not been established. The Direct Oral AntiCoagulants (DOACs) include PRADAXA® (Dabigatran), which is a direct Thrombin inhibitor and XARELTO® (Rivaroxaban), ELIQUIS® (Apixaban), SAVAYSA® (Endoxaban), BEVYXXA® (Betrixaban) which are Factor Xa inhibitors. Compared to COUMADIN® , the New Oral Anticoagulants have a rapid onset of action, wider therapeutic window, shorter half-lives (7-14 hours in healthy individuals), no laboratory monitoring and fixed dosing schedule. In the EINSTEIN trial which compared XARELTO® with LMWH followed by COUMADIN® in patients with acute symptomatic DVT or PE, only 5.5% of patients had active cancer at baseline.

This study was conducted to assess VTE recurrence rates in patients with active cancer, treated with either XARELTO® or FRAGMIN® (Dalteparin) and whether XARELTO® would offer an alternative treatment for cancer patients with VTE. SELECT-D (Selected Cancer Patients at Risk of Recurrence of Venous Thromboembolism) is a randomized, open-label, multicenter pilot trial in which patients with active cancer, who had symptomatic Pulmonary Embolism (PE), incidental PE, or symptomatic lower-extremity proximal Deep Vein Thrombosis (DVT) were enrolled to receive either XARELTO® or FRAGMIN®. Active cancer was defined as a diagnosis of cancer (other than Basal-cell or Squamous-cell skin carcinoma) in the previous 6 months, any treatment for cancer within the previous 6 months, recurrent or metastatic cancer, or cancer not in Complete Remission (hematologic malignancy). In this study, 58% of the patients had metastatic disease, approximately 25% of patients had Colorectal cancer and 83% were receiving chemotherapy at the time of their VTE. A total of 406 patients were randomly assigned in a 1:1 ratio to receive either FRAGMIN® 200 IU/kg SC once daily for the first 30 days and then 150 IU/kg SC daily for an additional 5 months or XARELTO® 15 mg orally twice daily for 3 weeks, then 20 mg once daily for a total of 6 months. Patients were assessed at 3-month intervals until month 12 and then at 6-month intervals until month 24. The primary outcome was VTE recurrence over 6 months, using compression ultrasound (CUS). Secondary outcomes were major bleeding and Clinically Relevant NonMajor Bleeding (CRNMB).

The cumulative VTE recurrence rate at 6 months was 11% for patients receiving FRAGMIN® and 4% for patients receiving XARELTO® (HR=0.43). The 6-month cumulative rate of major bleeding was 4% for FRAGMIN® and 6% for XARELTO® (HR= 1.83). Corresponding cumulative rate of CRNMB at 6 months was 4% and 13% respectively. Most major bleeding events were GI, and there were no CNS bleeds. Patients with esophageal or gastroesophageal cancer experienced more major bleeds with XARELTO® than with FRAGMIN® (36% versus 11%). Overall Survival at 6 months was 70% with FRAGMIN® and 75% with XARELTO®.

It was concluded that XARELTO® was associated with relatively low VTE recurrencein patients with cancer but with higher Clinically Relevant NonMajor Bleeding, compared with LMWH, FRAGMIN®. Comparison of an Oral Factor Xa Inhibitor With Low Molecular Weight Heparin in Patients With Cancer With Venous Thromboembolism: Results of a Randomized Trial (SELECT-D). Young AM, Marshall A, Thirlwall J, et al. Journal of Clinical Oncology 2018;36:2017-2023

Hyperprogressive Disease after Immunotherapy in Advanced Non-Small Cell Lung Cancer

SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 14% of all new cancers and 27% of all cancer deaths. The American Cancer Society estimates that for 2018 about 234,030 new cases of lung cancer will be diagnosed and over 154,050 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Immunotherapy with PD-1 (Programmed cell Death 1) and PD-L1 (Programmed cell Death Ligand 1) inhibitors have demonstrated a clear survival benefit both as a single agent or in combination, compared with standard chemotherapy, in both treatment-naive and previously treated patients for advanced Non Small Cell Lung Cancer (NSCLC). Immuno-Oncology therapies unleash the T cells by blocking the Immune checkpoint proteins, thereby resulting in T cell proliferation, activation and a therapeutic response.

Recent reports of an acceleration of tumor growth during immunotherapy, defined as HyperProgressive Disease (HPD), has been observed in 9% of advanced malignancies and in 29% of patients with Head and Neck cancer treated with PD-1/PD-L1 inhibitors. It has been postulated that high level of interferon gamma (IFN-gamma) usually released by PD-1 blockade may have detrimental effects on immunity. Alternatively PD-1/PD-L1 blockade may upregulate Interleukin 6, Interleukin 17, and neutrophil axis, generating a potent aberrant inflammation, responsible for immune escape and accelerated growth.

HyperProgressive Disease should be differentiated from Pseudoprogression. The later  is defined as progressive disease, followed by Complete Response and/or Partial Response or Stable Disease longer than 6 months. The Tumor Growth Rate (TGR) estimates the increase in tumor volume over time based on two Computed Tomography (CT) scan measurements. TGR can be used to quantitatively assess tumor dynamics and kinetics during treatment and can be specifically applied to identify the subset of patients experiencing HPD.

This study was conducted to investigate whether HPD is observed in patients with advanced NSCLC treated with PD-1/PD-L1 inhibitors compared with single-agent chemotherapy and whether there is an association between treatment and HPD. This multicenter, retrospective study included 406 consecutive eligible patients with confirmed Stage III or IV NSCLC treated with PD-1/PD-L1 inhibitors such as OPDIVO® (Nivolumab), KEYTRUDA® (Pembrolizumab), TECENTRIQ® (Atezolizumab), or IMFINZI® (Durvalumab) as monotherapy in second or later line treatment, at eight French institutions between November 2012 and April 2017. The control cohort included equivalent data collected on 59 eligible patients with advanced NSCLC, who had failed a Platinum-based regimen and received single-agent chemotherapy (Taxanes, Pemetrexed, Vinorelbine , or Gemcitabine) in 4 French institutions from August 2011, to June 2016. The median age was 50 years, over 70% of the patients had nonsquamous histology and approximately 20% of the patients had PD-L1 positive status (1% or more by IHC) confirmed. The median followup was 12.1 months. Measurable disease (defined by Response Evaluation Criteria in Solid Tumors – RECIST version 1.1) on at least two CT scans before treatment and one CT scan during treatment, was required. HyperProgressive Disease (HPD) was defined as disease progression on the first CT scan during treatment with an absolute increase in Tumor Growth Rate exceeding 50%. The Primary end point was assessment of the HyperProgressive Disease rate in patients treated with Immunotherapy or chemotherapy.

Among those treated with PD-1/PD-L1 inhibitors, HyperProgressive Disease was noted in 13.8% of patients. HPD was significantly associated with more than two metastatic sites prior to treatment with PD-1/PD-L1 inhibitors, compared with those without HPD (62.5% versus 42.6%; P=0.006). However, baseline tumor burden and number of previous lines of therapy did not make a significant difference. Patients experiencing HPD within the first 6 weeks of beginning PD-1/PD-L1 inhibitor therapy had significantly lower median Overall Survival compared with those with progressive disease without HyperProgression at the first evaluation (3.4 months versus 6.2 months; HR=2.18; P=0.003). Pseudoprogression was observed in 4.7% patients.

Among patients treated with single-agent chemotherapy, only 5.1% were classified as having HyperProgressive Disease and the median Overall Survival was 4.5 months in those with HPD and 3.9 months in other patients with progressive disease without HyperProgression at the first evaluation (P=0.60).

The authors concluded that HyperProgressive Disease is more common with PD-1/PD-L1 inhibitors compared with chemotherapy, among previously treated patients with advanced NSCLC, and is also associated with high number of metastatic sites at baseline and poor survival. They added that the present study is the largest analysis exploring HPD to date and is the first conducted, in a dedicated NSCLC population, with a control cohort of chemotherapy-treated patients Hyperprogressive Disease in Patients With Advanced Non–Small Cell Lung Cancer Treated With PD-1/PD-L1 Inhibitors or With Single-Agent Chemotherapy. Ferrara R, Mezquita L, Texier M, et al. JAMA Oncol. Published online September 6, 2018. doi:10.1001/jamaoncol.2018.3676

Smoking Associated with Increased Risk of Recurrence and Mortality among Prostate Cancer Patients after Curative Therapy

SUMMARY: Prostate cancer is the most common cancer in American men with the exclusion of skin cancer, and 1 in 9 men will be diagnosed with prostate cancer during their lifetime. It is estimated that in the United States, about 164,690 new cases of Prostate cancer will be diagnosed in 2018 and 29,430 men will die of the disease. Approximately 35% of the patients with Prostate cancer will experience PSA only relapse within 10 years of their primary treatment with Radical Prostatectomy or Radiation Therapy and a third of these patients will develop documented metastatic disease within 8 years following PSA only relapse. Several studies have addressed how diet and environmental factors affect the risk of Prostate cancer.

According to the American Cancer Society, tobacco use is responsible for nearly 1 in 5 deaths in the United States and accounts for at least 30% of all cancer deaths. Tobacco smoke contains more than 70 well known carcinogens and smoking is known as a preventable risk factor for several genitourinary malignancies cancers such as upper tract urothelial carcinoma, Bladder cancer and Renal Cell Carcinoma. The effect of smoking on the incidence of Prostate cancer has however remained unclear. Nicotine in tobacco smoke has been implicated as a disease driver and there is a significant correlation between smoking and multigene hypermethylation. Further, more unfavorable pathologic features have been noted during Radical Prostatectomy among smokers. Additionally, there is an independent association of cigarette smoking with time to castration resistance, in patients with advanced Prostate cancer undergoing Androgen Deprivation Therapy.

The purpose of this study was to systematically review and analyze the association of smoking status with biochemical recurrence, metastasis, and cancer-specific mortality among patients with localized Prostate cancer undergoing primary curative treatment with radical prostatectomy or radiotherapy. The authors performed a systematic search of original articles published between January 2000 and March 2017 using PubMed, MEDLINE, Embase, and Cochrane Library databases and they identified a total of 5157 studies of which 16 articles were selected for qualitative analysis and 11 articles were selected for quantitative analysis. All included studies were observational and nonrandomized. The meta-analysis overall included 22 549 patients, of whom 4202 (18.6%) were current smokers at the time of primary curative treatment, and 18,347 (81.4%) were nonsmokers (former and never smokers combined). The overall median follow-up was 72 months. The prespecified outcomes evaluated were, biochemical recurrence, metastasis, and cancer-specific mortality.

It was noted that current smokers had a significantly higher risk of experiencing BCR (BioChemical Recurrence) compared with nonsmokers whether they had undergone RP or RT (HR=1.40; P< 0.001). The same findings were noted among former smokers (HR=1.19; P<0.001). Current smokers were also at a higher risk of metastasis (HR=2.51; P<0 .001) and cancer-specific mortality (HR=1.89; P<0.001), but this was not observed among former smokers, for metastasis (HR=1.61; P=0.31) and cancer-specific mortality (HR=1.05; P=0.70).

It was concluded that current smokers at the time of primary curative treatment for localized Prostate cancer are at higher risk of experiencing Biochemical Recurrence, metastasis, and cancer-specific mortality, suggesting that smoking is a modifiable risk factor that affects all disease phases of Prostate cancer. Health Care Providers caring for Prostate cancer patients should be encouraged to counsel patients on smoking cessation, given the risk of poorer outcomes associated with smoking. The authors also noted that this is the first systematic review and meta-analysis that investigated the association of smoking with oncologic outcomes, after primary treatment for localized Prostate cancer. Association of Smoking Status With Recurrence, Metastasis, and Mortality Among Patients With Localized Prostate Cancer Undergoing Prostatectomy or Radiotherapy A Systematic Review and Meta-analysis. Foerster B, Pozo C, Abufaraj M, et al. JAMA Oncol. 2018;4:953-961.

FDA Approves KEYTRUDA® for Cervical Cancer

SUMMARY: The FDA on June 12, 2018, approved KEYTRUDA® (Pembrolizumab) for patients with recurrent or metastatic Cervical cancer with disease progression on or after chemotherapy, whose tumors express PD-L1 (Combined Positive Score-CPS, of 1 or more) as determined by an FDA-approved test. The American Cancer Society estimates that for Cervical cancer in the US for 2018, about 13,240 new cases of invasive Cervical cancer will be diagnosed and about 4,170 women will die of the disease. Cervical pre-cancers are diagnosed far more often than invasive Cervical cancer. Cervical cancer is most frequently diagnosed in women between the ages of 35 and 44 and in the US. Hispanic women are most likely to get Cervical cancer, followed by African-Americans, Asians and Pacific Islanders, and whites.

Approximately 5% of new diagnoses of Cervical cancer accounts for stage IV disease. However, metastatic disease develops in 15-60% of women, usually within the first two years of completing primary treatment. A select group of women with locally recurrent or limited metastatic disease may be potentially cured with surgical resection or radiotherapy. This however may not be feasible in the majority of cases. Patients with recurrent and metastatic Cervical cancer have a poor prognosis, with limited systemic treatment options. There is currently no consensus on the standard of care for second-line systemic treatment of recurrent or metastatic Cervical cancer, and as such represents a significant unmet clinical need.

KEYTRUDA® (Pembrolizumab) is a fully humanized, Immunoglobulin G4, anti-PD-1, monoclonal antibody, that binds to the PD-1 receptor and blocks its interaction with ligands PD-L1 and PD-L2. It thereby reverses the PD-1 pathway-mediated inhibition of the immune response and unleashes the tumor-specific effector T cells.

The FDA approval was based on KEYNOTE-158 study, which is a multicenter, non-randomized, open-label, multi-cohort phase II basket study trial, investigating the antitumor activity of KEYTRUDA® in 11 different advanced cancer types, who had progressed on standard-of-care therapy. Basket Trial by definition allows the testing of one drug on a single mutation in a variety of tumor types, at the same time, thereby potentially increasing the number of patients who are eligible to receive certain drugs. KEYTRUDA® was investigated in 98 patients with recurrent or metastatic Cervical cancer, enrolled in a single cohort of the KEYNOTE- 158 trial.

Key eligibility criteria for this cohort included patients with histologically or cytologically confirmed advanced Cervical cancer who had progressed on or intolerant to one or more lines of standard therapy and had tumor sample available for biomarker analysis. Patients were treated with KEYTRUDA® 200 mg IV every 3 weeks until documented disease progression or unacceptable toxicity..PD-L1 positivity, defined as a Combined Positive Score (CPS) of 1 or more, was evaluated retrospectively by ImmunoHistoChemistry (IHC) using the PD-L1 IHC 22C3 pharmDx Kit. Median age was 46 years and 77 patients (79%) of enrolled patients had PD-L1 positive tumors. Primary endpoint was Objective Response Rate (ORR) assessed by independent central review. Secondary endpoints included Duration of Response (DOR), Progression Free Survival (PFS), Overall Survival (OS) and safety.

With a median follow up time of 11.7 months, the ORR in the 77 PD-L1 positive patients was 14.3% including 2.6% Complete Responses and 11.7% Partial Responses. The estimated median response duration was not reached, 91% had response duration of 6 months or more, and no responses were observed in patients whose tumors did not have PD-L1 expression (CPS less than 1). The most common adverse reactions in at least 10% of patients were fatigue, fever, nausea, vomiting, diarrhea/colitis, abdominal pain, constipation, hypothyroidism, and dyspnea. KEYTRUDA® was discontinued due to adverse reactions in 8% of patients.

It was concluded that KEYTRUDA® is the first anti-PD-1 therapy approved for the treatment of advanced Cervical cancer, providing an important new second-line option for certain patients with this disease, with durable antitumor activity and manageable toxicity profile. Pembrolizumab treatment of advanced cervical cancer: Updated results from the phase 2 KEYNOTE-158 study. Chung HC, Schellens JH, Delord J, et al. J Clin Oncol 36, 2018 (suppl; abstr 5522)

American Cancer Society Updates Colorectal Cancer Screening Guideline for Average Risk Adults

The ACS recently updated Colorectal Cancer Screening Guideline using prevailing evidence as well as microsimulation modeling analyses. The new guideline does not prioritize among screening test options. This is because test preferences vary among individuals and the guidelines development committee emphasized that screening rates could be improved by endorsing the full range of tests without preference. Adults born around 1990 have twice the risk of colon cancer and four times the risk of rectal cancer compared with adults born around 1950, who have the lowest risk. In the updated guideline, screening is recommended earlier, starting at age 45 years and may be performed  with either a high-sensitivity stool-based test or a structural (visual) exam, depending on patient preference and test availability.

Role of Bone-Modifying Agents in Multiple Myeloma American Society of Clinical Oncology Clinical Practice Guideline Update

SUMMARY: Multiple Myeloma is a clonal disorder of plasma cells in the bone marrow and the American Cancer Society estimates that in the United States, 30,770 new cases will be diagnosed in 2018 and 12,770 patients are expected to die of the disease. Multiple Myeloma in 2018 remains an incurable disease. The therapeutic goal therefore is to improve Progression Free Survival (PFS) and Overall Survival (OS). ASCO recently issued a clinical practice guideline update on the role of Bone-Modifying Agents (BMA) in Multiple Myeloma following a systematic literature review of 35 relevant studies by an expert panel. In the updated guidelines, ASCO has recommended expanding the use of bisphosphonates to include all patients being treated for active Multiple Myeloma. The previous guidelines recommended BMAs only for patients with lytic disease. The new recommendation was based on results from the phase III MRC Myeloma IX Trial, which demonstrated the benefit of bisphosphonate therapy in patients with newly diagnosed multiple myeloma who did not have lytic bone disease.

Indications to initiate a BMA – Key Recommendations

Patients with lytic disease on plain radiographs or other imaging studies

For patients with Multiple Myeloma who, on plain radiograph(s) or other imaging studies (MRI or CT scan), have lytic destruction of the bone or compression fracture of the spine from osteopenia, AREDIA® (Pamidronate) 90 mg IV over at least 2 hours or ZOMETA® (Zoledronic acid) 4 mg IV over at least 15 minutes every 3 to 4 weeks is recommended. Alternative treatment includes the use of XGEVA® (Denosumab), a monoclonal antibody that targets Receptor Activator of Nuclear factor Kappa-B Ligand (RANKL).

Patients with solitary plasmacytoma or smoldering (asymptomatic) or indolent myeloma

Starting bisphosphonates in patients with Solitary Plasmacytoma or Smoldering (asymptomatic) or indolent Myeloma is not recommended.

Adjunct to pain control in patients with pain as a result of osteolytic disease and those receiving other interventions for fractures or impending fractures

AREDIA® or ZOMETA® IV is recommended for patients with pain as a result of osteolytic disease and as an adjunctive treatment of patients receiving radiation therapy, analgesics, or surgical intervention to stabilize fractures or impending fractures. XGEVA® is an additional option.

Patients with myeloma with normal plain radiograph or osteopenia in bone mineral density measurements

The Expert Panel supports starting intravenous bisphosphonates in patients with Multiple Myeloma with osteopenia (osteoporosis), but no radiographic evidence of lytic bone disease.

Patients with monoclonal gammopathy of undetermined significance

Starting bisphosphonates in patients with Monoclonal Gammopathy of Undetermined Significance is not recommended, unless osteopenia/osteoporosis exists.

Dosing and selection of BMAs

As a result of increased concerns over renal adverse events, Guidelines recommend that patients with preexisting mild to moderate renal impairment (estimated Creatinine Clearance, 30-60 mL/min) should receive a reduced dosage of ZOMETA®. No changes in infusion time or interval are required. ZOMETA® has not been studied in patients with severe renal impairment and is not recommended for use in these patients. Recent data that compare XGEVA® with ZOMETA® has demonstrated fewer adverse events related to renal toxicity with XGEVA®, and this may be preferred in patients with compromised renal function. AREDIA® 90 mg administered over 4-6 hours is recommended for patients with extensive bone disease and existing severe renal impairment (serum creatinine level more than 3.0 mg/dL (265 µmol/L or an estimated Creatinine Clearance of less than 30 mL/min. Although no dosing guidelines are available for patients with preexisting renal impairment, the Expert Panel recommends that clinicians consider reducing the initial AREDIA® dose in that setting. Infusion times less than 2 hours with AREDIA® or less than 15 minutes with ZOMETA® should be avoided.

Duration of therapy

The Expert Panel suggests that bone-targeting treatment continue for a period of up to 2 years. Less frequent dosing has been evaluated and should be considered in patients with responsive or stable disease. In patients who do not have active Myeloma and are on maintenance therapy, the physician may consider a 3-month interval of bisphosphonate administration. There are no data to support a more precise recommendation for the duration of bisphosphonate therapy in this group of patients. For those patients for whom bisphosphonates were withdrawn after 2 years, the drug should be resumed upon relapse with new-onset Skeletal Related Events. XGEVA® should not be stopped abruptly, given its reversible mechanism of action.

Monitoring

The Expert Panel recommends that serum creatinine should be monitored before each dose of AREDIA® or ZOMETA®, in accordance with FDA-approved labeling. XGEVA® does not require monitoring of renal function. In patients who develop renal deterioration without an apparent cause during bisphosphonate therapy, ZOMETA® or AREDIA® should be withheld. Bisphosphonate therapy can be resumed at the same dosage as that before treatment interruption, when serum creatinine returns to within 10% of the baseline level. XGEVA® requires no dose modification. Serum Calcium should be monitored regularly, and serum Vitamin D levels should be evaluated intermittently. Hypocalcemia is an adverse effect of all bone resorptive agents and is more pronounced with XGEVA®. Patients should be Calcium and Vitamin D repleted. The Expert Panel also recommends intermittent evaluation (every 3-6 months) of all patients receiving AREDIA® or ZOMETA® therapy for the presence of albuminuria, on a spot urine sample. In patients who experience unexplained albuminuria, a 24-hour urine collection should be obtained to assess for more than 500 mg/24 hours of urinary albumin, and discontinuation of the drug is advised until renal problems are resolved. These patients should be reassessed every 3-4 weeks with a 24-hour urine collection for total protein and Urine Protein ElectroPhoresis, and AREDIA® should be reinstituted over a longer infusion time (4 hours or more) and at doses not to exceed 90 mg every 4 weeks, when renal function returns to baseline. The Expert Panel supports the use of screening urinalysis for proteinuria, but underscores that a 24-hour urine collection for the determination of total protein and electrophoresis is required if the test is positive. Although no similar guidelines are available for ZOMETA®, some Expert Panel members recommend that ZOMETA® be reinstituted over a longer infusion time (30 minutes or more).

Biochemical markers

Use of the biochemical markers of bone metabolism to monitor bone-modifying therapy use, is not suggested for routine care.

Osteonecrosis of the jaw

OsteoNecrosis of the Jaw (ONJ) is an uncommon but potentially serious complication of IV bisphosphonates and XGEVA®. The Expert Panel agrees with the recommendations described in the revised FDA label for ZOMETA® and AREDIA®, Dear Doctor letters, a white paper, and various position papers or statements. All patients should receive a comprehensive dental examination and appropriate preventive dentistry before bone-modifying therapy. Active oral infections should be treated, and sites that are at high risk for infection should be eliminated. While on therapy, patients should maintain excellent oral hygiene and avoid invasive dental procedures, if possible. Continuation of a bone-targeting agent in the setting of ONJ has to be individualized and dependent on a risk-benefit ratio and the severity of bone disease.

Role of bone-modifying agents in multiple myeloma: American Society of Clinical Oncology clinical practice guideline update. Anderson K, Ismaila N, Flynn PJ, et al. J Clin Oncol. 2018;36:812-818.

HER2 Testing in Breast Cancer American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Focused Update

SUMMARY: Breast cancer is the most common cancer among women in the US and about 1 in 8 women (12%) will develop invasive breast cancer during their lifetime. Approximately 266,120 new cases of invasive breast cancer will be diagnosed in 2018 and about 40,920 women will die of the disease. The HER or erbB family of receptors consist of HER1, HER2, HER3 and HER4. Approximately 15-20% of invasive breast cancers overexpress HER2/neu oncogene, which is a negative predictor of outcomes without systemic therapy. HERCEPTIN® (Trastuzumab) is a humanized monoclonal antibody targeting HER2, and adjuvant and neoadjuvant chemotherapy given along with HERCEPTIN® reduces the risk of disease recurrence and death, among patients with HER2-positive, early stage as well as advanced metastatic breast cancer. Since the approval of HERCEPTIN®, several other HER2-targeted therapies have become available. Accurate determination of HER2 status of the tumor is therefore essential for patients with invasive breast cancer, to ensure that those most likely to benefit are offered a HER2-targeted therapy and those who are unlikely to benefit can avoid toxicities as well as financial burden associated with those drugs.

Laboratory testing for HER2 status in patients with breast cancer in the US is performed according to guidelines developed by an Expert panel of members of the American Society of Clinical Oncology (ASCO) and the College of American Pathologists (CAP). The ASCO/CAP guidelines were first published in 2007 and were updated in 2013. The Expert panel in 2018 developed and issued a focused update of the clinical practice guideline on HER2 testing in breast cancer. This new information made available since the previous update in 2013 addresses uncommon clinical scenarios and improves clarity, particularly for infrequent HER2 test results that are of uncertain biologic or clinical significance. There are currently two approved methods for determining HER2 status in breast cancer: ImmunoHistoChemistry (IHC) and In Situ Hybridization (ISH). This new guideline enables the Health Care Provider, how to best evaluate some of the less common patterns in HER2 results emerging from ISH.

Guideline Questions

1) What is the most appropriate definition for ImmunoHistoChemistry (IHC) 2+ (IHC equivocal)?

2) Must Human Epidermal growth factor Receptor 2 (HER2) testing be repeated on a surgical specimen if the initially tested core biopsy is negative?

3) What is the optimal algorithm for less common patterns observed when performing dual-probe In Situ Hybridization (ISH) HER2 testing in breast cancer?

Updated Recommendations

1) Immunohistochemistry (IHC) 2+ is defined as invasive breast cancer with weak to moderate complete membrane staining observed in more than 10% of tumor cells.

2) If the initial HER2 test result in a core needle biopsy specimen of a primary breast cancer is negative, a new HER2 test may (not “must”) be ordered on the excision specimen based on some criteria (such as tumor grade 3).

3)The HER2 testing algorithm now includes more rigorous interpretation criteria of the less common patterns that can be seen in about 5% of all cases when HER2 status in breast cancer is evaluated using a dual-probe ISH assay. These scenarios are described as ISH group 2 (HER2/Chromosome Enumeration Probe 17 [CEP17] ratio of 2.0 or more; average HER2 copy number less than 4.0 signals per cell), ISH group 3 (HER2/CEP17 ratio less than 2.0; average HER2 copy number 6.0 or more signals per cell), and ISH group 4 (HER2/CEP17 ratio less than 2.0; average HER2 copy number 4.0 or more and less than 6.0 signals per cell). These cases, described as ISH groups 2-4, should now be assessed using a diagnostic approach that includes a concomitant review of the IHC (ImmunoHistoChemistry) test, which will help the pathologist make a final determination of the tumor specimen as HER2 positive or negative.

4)The Expert Panel also preferentially recommends the use of dual-probe instead of single-probe ISH assays, but it recognizes that several single-probe ISH assays have regulatory approval in many parts of the world. 

Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer: American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline Focused Update. Wolff AC, Hammond EH, Allison KH, et al. J Clin Oncol 2018; 36:2105-2122.

A Completely Oral Chemotherapy-Free Regimen for Acute Promyelocytic Leukemia

SUMMARY: Acute Promyelocytic Leukemia (APL) is a subtype (M3) of Acute Myeloid Leukemia (AML) accounting for 5-10% of AMLs in adults. The diagnostic hallmark of this subtype of AML is the balanced reciprocal translocation involving the long arms of chromosomes 15 and 17 – t(15;17)(q22;q11-12), leading to the fusion of ProMyeLocytic (PML) gene with the Retinoic Acid Receptor Alpha (RARA) gene. This hybrid PML-RARA hybrid oncoprotein blocks the differentiation of promyelocytes resulting in APL. The median age for patients diagnosed with APL is around 40 years.

Patients with APL often present with life-threatening bleeding secondary to consumptive coagulopathy and more rarely thrombosis. Therefore, rapid diagnosis of APL and institution of anti-leukemic and supportive therapy is of paramount importance, to prevent bleeding related mortality. Given the early mortality rate of 17-29%, immediate institution of anti-leukemic therapy without delay is strongly recommended upon clinical suspicion of APL following morphologic evaluation of the bone marrow, pending cytogenetics. Invasive procedures, routinely done at initial presentation of AML, should be avoided. APL is a curable disease and approximately 80% of the all APL patients present with non-high risk disease (WBC 10,000 or less per microliter).

The FDA in early 2018 approved the use of TRISENOX® (Arsenic Trioxide) injection, in combination with VESANOID® (All-Trans Retinoic Acid (ATRA), Tretinoin), for the treatment of adults with newly diagnosed low-risk APL, whose APL is characterized by the presence of the t(15;17) translocation or PML/RARA gene expression. This approval was based on the superiority of Arsenic Trioxide plus ATRA which resulted in a to a 2-year Event-Free Survival (EFS) rate of 97%, compared with 86% for chemotherapy plus ATRA. The combination of chemotherapy-free ATRA and Intravenous Arsenic Trioxide is therefore considered the standard of care for non-high risk APL patients. TRISENOX® (Arsenic Trioxide) was initially approved by the FDA in 2000 for the treatment of patients with APL who are refractory or have relapsed on Retinoid and Anthracycline chemotherapy.

First published from China in the 1980’s, ATRA induces terminal differentiation of leukemic promyelocytes and leads to an immediate improvement in bleeding symptoms and almost complete resolution of the associated coagulopathy within 1-2 weeks of treatment. Arsenic Trioxide is probably the most effective single agent used in the treatment of APL. It directly binds to the PML‐RARA oncoprotein inducing its proteosomal degradation and leads to apoptosis of leukemic cells.

Arsenic Trioxide infusion requires hospitalization. There is however an oral tetra-arsenic tetra-sulfide (As4S4) -containing formulation, Realgar-Indigo naturalis Formula (RIF). In a previously published study, a more convenient oral RIF plus ATRA was found not to be inferior to intravenous Arsenic Trioxide plus ATRA, as first-line treatment in patients with APL (J Clin Oncol. 2013 ;31:4215-4221).

The authors in this study compared oral RIF plus ATRA treatment regimen with the standard intravenous Arsenic Trioxide plus ATRA treatment regimen in patients with non-high-risk APL. In this multicentre, non-inferiority, open-label, randomized, controlled phase III trial, patients with newly diagnosed (within 7 days) non-high-risk APL (N=109), were randomly assigned 2:1 to receive treatment with RIF-ATRA (N=72) or Arsenic Trioxide-ATRA (N=37) as the induction and consolidation therapy. Patients received RIF 60 mg/kg orally daily in divided doses or Arsenic Trioxide 0.15 mg/kg IV daily and ATRA 25 mg/m2 orally daily in divided doses. Treatment was continued until complete remission was achieved. The home-based consolidation therapy consisted of RIF 60 mg/kg orally daily in divided doses or Arsenic Trioxide 0.15 mg/kg IV daily, 4 weeks on and 4 weeks off for four cycles and ATRA 25 mg/m2 orally daily in divided doses, 2 weeks on and 2 weeks off for seven cycles. The median patient age was 35 years. The Primary outcome was Event-Free Survival at 2 years.

After a median follow up of 32 months, 97% of patients in the RIF-ATRA group and 94% in the Arsenic Trioxide-ATRA group had achieved 2-year Event-Free Survival confirming non-inferiority of RIF-ATRA compared with Arsenic Trioxide and ATRA (P=0.0017 for non-inferiority). The 2 year Overall Survival was 100% in the RIF-ATRA group and 94% in the Arsenic Trioxide-ATRA group (P=0.049). Toxicities during induction treatment included grade 3-4 hepatotoxity (elevated AST or ALT) in 9% of patients in the RIF-ATRA group versus 14% in the Arsenic Trioxide-ATRA group. Grade 3-4 infections were reported in 23% versus 42% in the two groups respectively. Two patients in the Arsenic Trioxide-ATRA group died during induction therapy (one from hemorrhage and one from thrombocytopenia).

It was concluded that oral RIF plus ATRA was not inferior to intravenous Arsenic Trioxide plus ATRA, for the treatment of patients with non-high-risk Acute Promyelocytic Leukemia. The authors suggested that this completely oral, chemotherapy-free therapy might be an alternative to the standard intravenous treatment for patients with non-high-risk APL. Oral arsenic plus retinoic acid versus intravenous arsenic plus retinoic acid for non-high-risk acute promyelocytic leukaemia: a non-inferiority, randomised phase 3 trial. Zhu HH, Wu DP, Du X, et al. Lancet Oncol. 2018;19:871-879