FDA Approves LONSURF®, A Novel Oral Agent for Refractory Colorectal Cancer

SUMMARY: The FDA on September 22, 2015 approved LONSURF® (Trifluridine/Tipiracil) for the treatment of patients with metastatic ColoRectal Cancer (CRC), who have been previously treated with Fluoropyrimidine, Oxaliplatin and Irinotecan-based chemotherapy, an anti-VEGF biological therapy and if RAS wild-type, an anti-EGFR therapy. The American Cancer Society estimates that approximately 133,000 new cases of ColoRectal Cancer (CRC) will be diagnosed in the United States in 2015 and close to 50,000 are expected to die of the disease. Approximately 15-25% of the patients with CRC present with metastatic disease at the time of diagnosis (synchronous metastases) and 50-60% of the patients with CRC will develop metastatic disease during the course of their illness. Patients with metastatic CRC, whose disease has progressed after treatment with standard therapies, have limited therapeutic options available, to treat their disease.

LONSURF® is a combination of two agents – a novel oral nucleoside, Trifluridine and a thymidine phosphorylase inhibitor, Tipiracil hydrochloride. This combination has a unique mechanism of action. Trifluridine, the active ingredient of LONSURF® incorporates into DNA resulting in DNA damage. Degradation of Trifluridine which occurs when taken orally is prevented by Tipiracil hydrochloride.

The RECOURSE study is a pivotal, global, phase III trial, in which 800 patients with metastatic ColoRectal Cancer, refractory to all standard therapies were randomly assigned in a 2:1 ratio to receive either LONSURF® (N=534) or placebo (N=266). Patients received LONSURF® 35mg/m2 or matching placebo orally, twice daily after meals, on Days 1-5 and 8-12 of each 28 day cycle. Treatment was continued until disease progression or unacceptable toxicity. Eligible patients had metastatic ColoRectal Cancer (mCRC), previously treated with chemotherapy and biological therapy, which included Fluoropyrimidine, Oxaliplatin and Irinotecan-based chemotherapy, an anti-VEGF biological therapy and if RAS wild-type, an anti-EGFR therapy. The primary endpoint of this study was overall survival and the secondary endpoint was progression-free survival.

It was noted that LONSURF® significantly improved Overall Survival compared to placebo (7.1 months vs 5.3 months; HR=0.68; P<0.001), with a 32% reduction in the risk of death. LONSURF® also significantly improved Progression Free Survival compared to placebo (HR = 0.47; P<0.001). The most common grade 3 or more adverse events were leukopenia (21%), anemia (18%) and febrile neutropenia (4%), noted in patients receiving LONSURF®. The authors concluded that LONSURF® significantly improved Overall Survival in patients with refractory metastatic ColoRectal Cancer, providing a novel oral therapeutic option for this patient group. Randomized Trial of TAS-102 for Refractory Metastatic Colorectal Cancer. Mayer RJ, Van Cutsem E, Falcone A, et al. N Engl J Med 2015; 372:1909-1919

Preserving Fertility with ZOLADEX® in Breast Cancer

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, 231,840 new cases of invasive breast cancer will be diagnosed in 2015 and over 40,000 women will die of the disease. Approximately 75% of patients with breast cancer are hormone receptor positive (Estrogen Receptor/Progesterone Receptor positive) and this is a predictor of response to endocrine therapy. In premenopausal woman, the ovary is the main source of estrogen production, whereas in postmenopausal women, the primary source of estrogen is the Aromatase enzyme mediated conversion of androstenedione and testosterone to estrone and estradiol in extragonadal/peripheral tissues. Premature Ovarian Failure (POF) is a common unintended consequence of chemotherapy in premenopausal women. Besides of loss of fertility, which can influence treatment decisions in young women, ovarian failure can lead to menopausal symptoms, sexual dysfunction and loss of bone density.

POEMS (Prevention of Early Menopause Study) is a randomized phase III trial designed to evaluate whether the addition of LHRH (Luteinizing Hormone-Releasing Hormone) analog Goserelin (ZOLADEX®), which suppresses the production of estrogens, to Cyclophosphamide based chemotherapy, would reduce POF in breast cancer patients, when compared to chemotherapy alone. Premenopausal patients less than 50 years of age, with hormone receptor negative (ER/PR negative ), Stage I-IIIA breast cancer, scheduled to receive chemotherapy, were randomly assigned to receive standard Cyclophosphamide based chemotherapy with or without monthly ZOLADEX® . Patients in the ZOLADEX® group received 3.6 mg SQ starting 1 week prior to the first dose of chemotherapy.

The primary endpoint was ovarian failure at two years (defined as amenorrhea for the prior 6 months AND post-menopausal FSH level). Other endpoints included pregnancy and survival rates. The median age of the patients was 38 years and median follow up was 4.1 years. Of the 218 evaluable patients, 135 premenopausal women were evaluable for the primary end point. POF rates were 22% in the chemotherapy alone group and 8% in the ZOLADEX® group (P=0.04). When the definition of POF was more liberal to include EITHER amenorrhea or elevated FSH but not both, POF rates were 45% in the chemotherapy alone group and 20% in the ZOLADEX® group (P=0.006). Among the 218 evaluable patients, more women in the ZOLADEX® group achieved at least one pregnancy (21%) compared to 11% in the chemotherapy alone group (P=0.03). Secondary outcomes also favored the ZOLADEX® group with a Disease free Survival (DFS) rate of 78% in the chemotherapy alone group compared with 89% in the ZOLADEX® group (P=0.04) and Overall Survival (OS) rate of 82% in the chemotherapy alone group compared with 92% in the ZOLADEX® group (P=0.05).

The authors concluded that the addition of ZOLADEX® to chemotherapy improved fertility prospects with a lower incidence of Premature Ovarian Failure and more pregnancies. Further, the improved Disease Free Survival and Overall Survival are important additional perks and prevention of Premature Ovarian Failure with ZOLADEX® may be a consideration not only in premenopausal breast cancer patients but also in other malignancies such as lymphomas, when treated with similar chemotherapeutic agents. Goserelin for Ovarian Protection during Adjuvant Chemotherapy for Breast Cancer. Moore HC, Unger JM, Phillips K, et al. N Engl J Med 2015; 372:923-932

FDA Approves KEYTRUDA® for Advanced Lung Cancer

SUMMARY: The FDA granted accelerated approval to KEYTRUDA® (Pembrolizumab), for the treatment of patients with metastatic Non Small Cell Lung Cancer (NSCLC), whose tumors express Programmed Death Ligand 1 (PD-L1), as determined by an FDA-approved test, following disease progression on or after platinum-containing chemotherapy. Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 27% of all cancer deaths. It is the leading cause of cancer death among both men and women. The American Cancer Society estimates that over 221,200 new cases of lung cancer will be diagnosed in the United States in 2015 and over 158,000 patients will die of the disease. Non Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers.

The treatment paradigm for solid tumors has been rapidly evolving with a better understanding of the Immune checkpoints. Immune checkpoints are cell surface inhibitory proteins/receptors that are expressed on activated T cells. They harness the immune system and prevent uncontrolled immune reactions. Survival of cancer cells in the human body may be to a significant extent, related to their ability to escape immune surveillance, by inhibiting T lymphocyte activation. The T cells of the immune system therefore play a very important role in modulating the immune system. Under normal circumstances, Immune checkpoints or gate keepers, switch off the T cells of the immune system and thereby inhibit an intense immune response. With the recognition of Immune checkpoint proteins and their role in suppressing antitumor immunity, antibodies have been developed, that target the membrane bound inhibitory Immune checkpoint proteins/receptors such as CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4), also known as CD152, PD-1(Programmed cell Death-1), etc. Targeting Immune checkpoints unleashes the T cells, resulting in T cell proliferation, activation and a therapeutic response. KEYTRUDA® 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, thereby undoing PD-1 pathway-mediated inhibition of the immune response and unleashing the tumor-specific effector T cells.

In this publication, the authors assessed the efficacy and safety of KEYTRUDA® in patients with advanced NSCLC enrolled in the KEYNOTE-001 phase I trial. Four Hundred and Ninety five (N=495) patients were assigned to either a training group (N=182) or a validation group (N=313) and KEYTRUDA® was administered at three dosages: 2 mg/kg IV every 3 weeks, 10 mg/kg IV every 3 weeks, or 10 mg/kg IV every 2 weeks. Patient responses were assessed every 9 weeks.

The Objective Response Rate (ORR) in the entire study population was 19.4%, the median Duration of Response was 12.5 months, the median Progression Free Survival was 3.7 months and the median Overall Survival was 12.0 months. The PD-L1 (Programmed Death-Ligand 1) expression was evaluated in 204 patients in the validation group by ImmunoHisto Chemistry (IHC) and membrane PD-L1 expression of 50% or more, in tumor cells, was selected as the cutoff. It was noted that among patients with PD-L1 expression in at least 50% of tumor cells, the Objective Response Rate was 45.2%, median Progression Free Survival was 6.3 months and median Overall Survival has not been reached. Responses were not as robust in those patients with tumors demonstrating less than 50% PD-L1 expression, but in those who did respond, the duration of responses were comparable to those with 50% or more PD-L1 expression. KEYTRUDA® was well tolerated overall and the common immune mediated adverse events were infusion reactions, hypothyroidism and pneumonitis.

The authors concluded that KEYTRUDA® showed significant antitumor activity in patients with advanced Non Small Cell Lung Cancer, whose tumor PD-L1expression was 50% or more. Further, the median duration of response exceeded 12 months among responders, regardless of the degree of PD-L1 expression. This study validated that PD-L1 expression in tumors is clearly a marker of response to KEYTRUDA®. Pembrolizumab for the Treatment of Non–Small-Cell Lung Cancer. Garon EB, Rizvi NA, Hui R, et al. N Engl J Med 2015; 372:2018-2028

Breast Cancer Screening Imaging Modalities – A Primer

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, 231,840 new cases of invasive breast cancer will be diagnosed in 2015 and over 40,000 women will die of the disease. Screening mammography complemented by breast self exam and clinical breast exam has resulted in early detection of breast cancer and successful outcomes. Even though mammography is a sensitive screening test, a small percentage of breast cancers may not show up on mammograms but may be palpable on examination by the patient or the clinician. Further, mammograms are less likely to find breast tumors in younger women with dense breast tissue. The following is a brief overview of the imaging techniques for breast cancer screening

Mammography

Mammography is performed by compressing the breast firmly between two plates and utilizes ionizing radiation to image breast tissue. During routine screening, breast tissue from the nipple to the pectoral muscle in the mediolateral oblique and craniocaudal views, is included. The radiation exposure is 4 to 24 mSv per standard two view screening examination. Two view screening is associated with a lower recall rate and lower interval cancer rates than are single-view exams. Breast Imaging Reporting and Data System (BI-RADS) categories are used for reporting mammographic results as follows:

0: Incomplete—needs additional image evaluation and/or prior mammograms for comparison.

1: Negative.

2: Benign.

3: Probably benign.

4: Suspicious.

5: Highly suggestive of malignancy.

6: Known biopsy—proven malignancy.

A digital mammogram is more expensive than screen-film mammography (SFM) and the data can be stored and shared. Compared with film mammography, sensitivity is higher for digital mammography, particularly in women younger than 50 years, but the specificity is either the same or lower than film mammography.

Computer-Aided Detection (CAD) systems increase detection of ductal carcinoma in situ (DCIS) by highlighting suspicious regions in the breast such as clustered microcalcifications and masses in mammograms. There is however no improvement in invasive cancer detection rate and there is an increase in recall rate.

Tomosynthesis

Tomosynthesis, or 3-Dimensional (3-D) mammography involves multiple short-exposure x-rays, from different angles and a three dimensional image is created for better visualization. A combination of 2-D and 3-D mammography has been reported to be more accurate than 2-D mammography alone, with the caveat that the radiation exposure to the patient is essentially doubled. Tomosynthesis in the diagnostic setting is at least as effective as spot compression views, for workup of non-calcified abnormalities, including asymmetries and distortions and may decrease the need for ultrasound testing.

Ultrasonography

Primarily utilized for the diagnostic evaluation of palpable or mammographically detected masses and distinguish solid tumors from cysts. It is a helpful adjunct modality in women with dense breast tissue. Images are created using high frequency sound waves with no radiation exposure. Evidence is lacking to support the use of ultrasound instead of mammography, at any age, in population based breast cancer screening.

Thermography

Thermography uses infrared imaging techniques and identifies temperature changes in the skin as an indicator of an underlying tumor. These changes are displayed in color patterns. The impact of thermography on breast cancer detection or mortality, has not been evaluated in randomized clinical trials and there appears to be no additional benefit for the use of thermography as an adjunct modality, for breast cancer screening.

Magnetic Resonance Imaging

Magnetic Resonance Imaging (MRI) is more sensitive than mammography although the specificity of a breast MRI is lower, resulting in a higher rate of false-positive findings and potentially unnecessary biopsies. Microcalcifications in the breast can be missed by a breast MRI. The American Cancer Society (ACS) recommends an annual MRI as an adjunct to screening mammogram and clinical breast exam in certain groups with increased risk of breast cancer. They include individuals with deleterious genetic mutations such as BRCA1/2 mutation carriers, a strong family history of breast cancer, or several genetic syndromes such as Li-Fraumeni or Cowden disease. MRI may also be used to evaluate the integrity of silicone breast implants, assess palpable masses following surgery or radiation therapy, detect mammographically and sonographically occult breast cancer in patients with axillary nodal metastasis and preoperative planning for some patients with known breast cancer. Breast MRI is performed preferably between days 7-15 of menstrual cycle for premenopausal women, using a dedicated breast coil, with the ability to perform a biopsy under MRI guidance by experienced radiologists, during the same visit.

Molecular Breast Imaging

Molecular Breast Imaging (MBI) involves the injection of technetium-99m (Tc-99m) sestamibi, a radioactive substance, which then allows tumor visualization with a gamma camera. MBI along with mammography significantly increased the cancer detection rate in women with mammographically dense breasts, compared to mammography alone, in a recent study. This new technology is not yet widely available.

References: 1) American Cancer Society recommendations for early breast cancer detection in women without breast symptoms. http://www.cancer.org/cancer/breastcancer 2) National Cancer Institute: PDQ® Breast Cancer Screening. Bethesda, MD

Genetics of Breast Cancer – A Primer

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, 231,840 new cases of invasive breast cancer will be diagnosed in 2015 and over 40,000 women will die of the disease. Approximately 5% to 10% of breast cancers are hereditary. The discovery of several new genetic mutations which can increase the risk of breast cancer, helped better understand inherited breast cancer susceptibility.

Genetic mutations in Breast cancer can be grouped into three categories:

1) High penetrance genes such as BRCA1 and BRCA2 gene mutations which account for 15–25% of the inherited breast cancers, TP53 gene mutations which cause the Li–Fraumeni syndrome, PTEN gene mutations which cause Cowden syndrome, STK11 gene mutations which cause Peutz–Jeghers syndrome and CDH1 gene mutations which cause hereditary diffuse gastric cancer. Under normal circumstances, the proteins produced from these genes act as tumor suppressors and are involved in repairing damaged DNA, which in turn helps to maintain the stability of a cell's genetic information. These gene mutations are rare and can result in a 10 fold increase in breast cancer risk.

2) Intermediate penetrance gene mutations increase the risk of breast cancer two to four fold. They include ATM, CHEK2, BRIP1, BARD1, and PALB2 gene mutations. Some of these genes provide instructions for making proteins that interact with the proteins produced from the BRCA1 or BRCA2 genes.

3) Low penetrance gene mutations such as FGFR2 gene mutations

MULTIGENE PANEL TESTING

Multigene panel testing can detect several more than the abnormal genes mentioned above and may also incidentally pick up an unexpected abnormal gene which may be associated with a low risk for cancer. This information can be emotionally stressful for patients, as there is little or no guidance regarding management. Further, multigene panel testing may find “Variants of Uncertain Significance” (VUS) which are genetic mutations that may or may not be linked to a disease. It is therefore imperative to counsel patients and families before and after genetic testing and adequate resources should be allocated to properly interpret the test results to these individuals.

WHICH GENES TO TEST

Actionable information from multigene panel testing can significantly benefit patients and family members. The testing panel should include BRCA1 and BRCA2 gene mutations as close to 10% of breast cancer patients with a strong family history who undergo multigene panel testing will have a deleterious mutation. Amongst them, about 6% will have BRCA1 or BRCA2 mutation and 4% will have gene mutations other than BRCA1and BRCA2. The panel testing should also include PALB2 gene mutations which carries a lifetime breast cancer risk of 33% to 58%, as well as CHEK2, ATM, and TP53 gene mutations for estrogen receptor positive breast cancer patients.

WHO SHOULD BE TESTED

1) A gene mutation linked to breast cancer is more likely if

2) Family is of Ashkenazi (Eastern European) Jewish descent.

3) Two or more first-degree (parent, sibling, or child) or second-degree (grandmother, granddaughter, aunt, niece, half-sibling) relatives were diagnosed with breast or ovarian cancer.

4) Breast cancer diagnosed before the age of 50 (premenopausal) in a close relative.

5) There is a family history of both breast and ovarian cancer.

6) Bilateral breast cancer was diagnosed in a close relative.

7) Male relatives were diagnosed with breast cancer.

8) Breast cancer is diagnosed in family and either male relatives on the same side of the family have had prostate cancer at a young age, or male or female relatives on the same side of the family have had gastrointestinal cancers, such as cancer of the pancreas, gall bladder or stomach.

Antoniou AC, Casadei S, Heikkinen T, et al. N Engl J Med 2014; 371:497-506.

National Comprehensive Cancer Network: Genetic/Familial High-Risk Assessment, Version 2.2015

First Line AVASTIN® plus Chemotherapy Combination Improves Overall Survival in High Risk Ovarian Cancer Patients

SUMMARY: The American Cancer Society estimates that over 21,000 women will be diagnosed with Ovarian cancer in the United States for 2015 and over 14,000 will die of the disease. Ovarian cancer ranks fifth in cancer deaths among women, accounting for more deaths than any other cancer of the female reproductive system. The FDA in 2014 approved AVASTIN® (Bevacizumab) in combination with Paclitaxel, Pegylated Liposomal Doxorubicin, or Topotecan, for the treatment of patients with Platinum-resistant, recurrent epithelial Ovarian, Fallopian tube, or Primary Peritoneal cancer. The approval was based on the AURELIA Open-Label Randomized Phase III Trial which concluded that AVASTIN® in combination with chemotherapy significantly improved Progression Free Survival and Objective Response Rates, in patients with Platinum Resistant, Recurrent Ovarian Cancer.

ICON7 is an open-label, randomized, phase III trial, in which the safety and efficacy of combining AVASTIN® with standard chemotherapy was evaluated, in patients with Newly Diagnosed Ovarian Cancer. One thousand five hundred and twenty eight (n=1528) patients were enrolled and eligible women with newly diagnosed Ovarian cancer had either early stage disease (FIGO Stage I–IIa, grade 3 or clear cell histology) or more advanced disease (FIGO Stage IIb–IV) disease. Patients had undergone debulking, cytoreductive surgery, or in those with advanced disease, had a biopsy for tissue diagnosis, with no further surgery planned. High risk disease in this study was defined as Stage IV disease, inoperable Stage III disease, or suboptimally debulked (more than 1 cm) Stage III disease. Patients were randomly assigned in a 1:1 ratio to receive either 6 cycles of combination chemotherapy with PARAPLATIN® (Carboplatin) AUC of 5 or 6 and TAXOL® (Paclitaxel) 175mg/m2 IV, given every 3 weeks or the same chemotherapy regimen given concurrently with AVASTIN® (Bevacizumab) 7.5mg/kg IV, every 3 weeks for 6 cycles followed maintenance AVASTIN® given IV every 3 weeks for 12 additional cycles or until disease progression, which ever was the earlier. The median age was 57 years. The Primary endpoint was Progression Free Survival (PFS). Secondary endpoints included Overall Survival and Safety outcomes of adverse events. The median follow up was 48•9 months.

The Primary endpoint of Progression Free Survival (PFS) has been previously reported and was 21•8 months with the addition of AVASTIN® to chemotherapy compared with 20•3 months with chemotherapy alone, in the entire study population (HR=0•81; P=0•004). However, in the predefined high risk population of patients with suboptimally cytoreduced stage III or stage IV disease, the PFS with the addition of AVASTIN® to chemotherapy was 18•1 months versus 14•5 months (HR=0•73; P=0•002).

In this publication, the authors reported the final Overall Survival results of the ICON7 trial. They noted no difference in the Overall Survival between AVASTIN® plus chemotherapy versus chemotherapy alone groups. (45.5 months vs 44.6 months, P=0.85). However, in the predefined group of high risk patients with inoperable or suboptimally cytoreduced stage III or stage IV disease, there was an Overall Survival benefit, with a mean Overall survival of 39•3 months in the AVASTIN® plus chemotherapy group versus 34•5 months in the chemotherapy alone group (P=0•03). This survival benefit was not seen in clear cell, early stage high grade, or low grade serous tumors. It is hypothesized that the effect of AVASTIN® on the tumor microenvironment is dependent on residual tumor burden, which is presumably producing VEGF (Vascular Endothelial Growth Factor). The authors concluded that the Overall Survival benefit with a combination of AVASTIN® and chemotherapy is best accomplished in newly diagnosed Ovarian cancer patients, with poor prognostic factors. Oza AM, Cook AD, Pfisterer J, et al. Lancet Oncol 2015;16:928-936. Standard chemotherapy with or without bevacizumab for women with newly diagnosed ovarian cancer (ICON7): overall survival results of a phase 3 randomised trial

NCCN Recommends Universal Screening for Lynch Syndrome in Patients with Newly Diagnosed Colorectal Cancer

SUMMARY: The American Cancer Society estimates that in the United States, for the year 2015, approximately 140,000 new cases of ColoRectal Cancer (CRC) will be diagnosed and close to 50,000 patients will die of the disease. The lifetime risk of developing ColoRectal Cancer is about 1 in 20 (5%). Lynch Syndrome (Hereditary NonPolyposis Colorectal Cancer – HNPCC), is an Autosomal Dominant, inherited disorder, associated with an increased risk of colorectal, endometrial, ovary, gastric, small bowel, pancreatic, brain, ureter or renal pelvis cancer. Approximately 3 to 5 percent of all cases of ColoRectal Cancer, are caused by Lynch Syndrome (LS) and 1 in 35 patients with newly diagnosed ColoRectal Cancer is related to Lynch Syndrome. Four MMR genes (MisMatch Repair genes), MLH1, MSH2, MSH6, and PMS2 are involved in the repair of mistakes that occur during DNA replication. When any of these genes are mutated, repair of DNA replication mistakes is prevented resulting in continuous division of abnormal cells and possibly cancer. The EPCAM gene lies next to the MSH2 gene on chromosome 2 and mutations in the EPCAM gene can cause the MSH2 gene to be inactivated, interrupting DNA repair and leading to accumulation of DNA replication errors and possible malignancy. Germline mutations in the MMR genes, is classically seen in Lynch Syndrome and results in microsatellite instability in tumors. Tumors are described as MSI-High when they have changes in 2 or more, of the 5 microsatellite markers. So, high levels of MSI within a tumor are suggestive of defective DNA mismatch repair. MSI-H is a hallmark of Lynch syndrome. However MSI-H is present in approximately 15% of patients with sporadic CRC. This is secondary to epigenetic silencing of MLH1 through promoter hypermethylation, rather than germline mutations in the MMR genes.

A Clinical Diagnosis of Lynch Syndrome can be made based on personal and family history if at least three relatives have a malignancy associated with Lynch Syndrome such as colorectal, endometrial, small bowel, ureter or renal pelvis cancer. In addition the following criteria should be met: • One relative must be a first-degree relative of the other two. • At least two successive generations must be affected. • At least one relative with a Lynch syndrome associated cancer should be diagnosed before 50 years of age. • Familial Adenomatous Polyposis should be excluded. • Tumors should be verified whenever possible. Because family history can sometimes be difficult to obtain or confirm, NCCN in those circumstances has recommended screening all newly diagnosed colorectal cancer patients for Lynch syndrome.

ImmunoHistoChemistry (IHC) staining can be performed on the tumor tissue for protein expression of the four MMR genes. IHC test is described as normal when all 4 mismatch repair proteins are normally expressed suggesting that an underlying mismatch repair gene mutation is unlikely. When IHC test is abnormal, it means that that at least one of the 4 mismatch repair proteins is not expressed and an inherited mutation may be present in the gene related to that protein. This can be further confirmed by mutation analysis of the corresponding gene. However, the lack of expression of MMR proteins by IHC is highly concordant with molecular MSI testing and IHC is therefore more practical and cost-effective. Tumors with loss of MMR protein expression or MSI-H are classified as MMR deficient (dMMR). Patients with sporadic tumors with MSI-H or MMR deficiency (dMMR) generally are older women with stage II disease and present with tumors in the proximal colon and the tumors are poor differentiated with increased number of tumor-infiltrating lymphocytes. These patients in retrospective studies had superior stage-adjusted survival compared to MMR proficient tumors. Further, single agent 5-Fluorouracil when given in an adjuvant setting was not beneficial in this patient group.

It should also be noted that a majority of colon cancer tumors that lack protein expression on IHC staining of MLH1 (often coexisting with loss of PMS2) are often due to an acquired genetic defect. If the IHC indicates absence of MLH1 protein expression, tumor should be tested for BRAF mutation V600E, which can be seen in sporadic colorectal cancers, but rarely found in patients who have Lynch Syndrome. Once a diagnosis of Lynch Syndrome is made, at risk family members should undergo colonoscopic evaluation at 20-25 years of age or 2-5 years prior to the earliest colon cancer, if it is diagnosed before age 25 and is repeated every 1-2 years. Prophylactic hysterectomy and bilateral salpingo-oophorectomy (BSO) should be considered by women who have completed childbearing. NCCN Guidelines Version 1.2014 Lynch Syndrome

Superior Outcomes with GAZYVA® and TREANDA® Combo in Indolent Non Hodgkin Lymphoma

SUMMARY: The American Cancer Society estimates that in 2015, about 71,850 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 19,800 individuals will die of this disease. Indolent Non Hodgkin Lymphomas are mature B cell lymphoproliferative disorders and include Follicular Lymphoma, Nodal Marginal Zone Lymphoma (NMZL), Extranodal Marginal Zone Lymphoma (ENMZL) of Mucosa-Associated Lymphoid Tissue (MALT) lymphoma, Splenic Marginal Zone Lymphoma (SMZL), LymphoPlasmacytic Lymphoma (LPL) and Small Lymphocytic Lymphoma (SLL). Follicular Lymphoma is the most indolent form and second most common form of all NHLs and they are a heterogeneous group of lymphoproliferative malignancies. Approximately 20% of all NHLs are Follicular Lymphomas. Advanced stage indolent NHL are not curable and as such prolonging Progression Free Survival (PFS) and Overall Survival (OS) while maintaining quality of life (QoL), has been the goals of treatment intervention. Asymptomatic patients with indolent NHL are generally considered candidates for “watch and wait” approach, whereas those with B symptoms (fever, night sweats, and weight loss), painful lymphadenopathy/splenomegaly, organ compromise and cytopenias are generally considered candidates for therapy.

GAZYVA® (Obinutuzumab) is glycoengineered, fully humanized, third generation, type II anti-CD20 antibody (IgG1 monoclonal antibody) that selectivity binds to the extracellular domain of the CD20 antigen on malignant human B cells. By virtue of binding affinity of the glycoengineered Fc portion of GAZYVA® to Fcγ receptor III on innate immune effector cells such as natural killer cells, macrophages and neutrophils, Antibody-Dependent Cell-mediated Cytotoxicity (ADCC) and Antibody-Dependent Cellular phagocytosis is significantly enhanced, whereas it induces very little Complement-Dependent Cytotoxicity. This is in contrast to RITUXAN® (Rituximab), which is a first generation type I, chimeric anti-CD20 targeted monoclonal antibody that kills lymphoma cells primarily by Complement-Dependent Cytotoxicity and also ADCC.

GADOLIN is a pivotal multicenter, open-label phase III, study in which TREANDA® (Bendamustine) alone was compared with TREANDA® plus GAZYVA® followed by GAZYVA®, in patients with indolent NHL (iNHL), refractory to RITUXAN®. Four hundred and thirteen (N=413) RITUXAN® refractory iNHL were randomized and patients in the control arm received TREANDA® 120 mg/m2 IV on days 1 and 2 every 28 days for a total of 6 cycles. Patients in the experimental arm received TREANDA® 90 mg/m2 IV on days 1 and 2 every 28 days for 6 cycles and GAZYVA® 1000mg IV days 1,8 and 15 every 28 days of cycle 1 and on day 1 of cycles 2-6. In patients with non-progressive disease in the experimental arm, GAZYVA® was continued (maintenance) every 2 months for up to 2 years. Both treatment groups were well balanced and the median age was 63 years, with a median of two prior lines of therapy. More than 90% of patients in each treatment group were refractory to their previous therapy and between 76% and 81% were double-refractory to both RITUXAN® and an alkylating agent. The Primary end point was Progression Free Survival (PFS) and Secondary end points included Overall Survival and Response Rate.

The study was unblinded at the time of planned interim analysis and had to be halted early, upon recommendations from the Independent Data Monitoring Committee, as the primary end point was reached. The median Progression Free Survival was 29 months with GAZYVA®/ TREANDA® plus maintenance GAZYVA® versus 14 months with TREANDA® monotherapy and no maintenance (HR=0.52; P<0.001). This meant a 45% reduction in the rate of disease progression. There was however no difference in the Response Rates between the treatment groups and the best Overall Response Rate up to 12 months from start of treatment was, 76.6% in the TREANDA® alone group and 78.6% in the TREANDA® plus GAZYVA® group. Median Overall Survival has not yet been reached in either arm and longer follow up is needed. The combination experimental group experienced more grade 3 adverse events such as infusion related reactions and neutropenia whereas the TREANDA® alone group experienced more thrombocytopenia, anemia and pneumonia. The authors concluded that GAZYVA® in combination with TREANDA® is superior to TREANDA® alone, in patients with RITUXAN® refractory indolent Non Hodgkin Lymphoma, with a significant improvement in Progression Free survival. The lack of difference in the Response Rate begs the question, if the improvement in PFS was predominantly contributed by the continuous maintenance treatment with GAZYVA®. GADOLIN: Primary results from a phase III study of obinutuzumab plus bendamustine compared with bendamustine alone in patients with rituximab-refractory indolent non-Hodgkin lymphoma. Sehn LH, Chua NS, Mayer J, et al. J Clin Oncol 33, 2015 (suppl; abstr LBA8502)

Stereotactic Body Radiation Therapy (SBRT) Instead of Surgery for Patients with Early Stage Inoperable or Advanced Oligometastatic NSCLC

SUMMARY: Stereotactic RadioSurgery (SRS) is a non-surgical procedure that allows delivery of significantly higher doses of precisely focused radiation to the tumor, compared to conventional radiation therapy, with less collateral damage to the surrounding normal tissue. The technologies used for SRS include GAMMA KNIFE® which uses highly focused gamma rays, Proton Beam therapy which uses ionized hydrogen or Protons, Linear Accelerator (LINAC) and CYBER KNIFE® which use Photons, to target the tumor tissue. Stereotactic Body Radiation Therapy (SBRT) refers to stereotactically guided radiation therapy delivered over several days. Because SBRT is fractionated and is offered in three precise treatments, the short-and long-term side effects of radiation therapy are decreased and may allow higher total dosage to be given.

SBRT is a viable option for elderly and frail patients and those with comorbidities or those who decline surgery. Two studies presented at the 56th Annual Meeting of the American Society for Radiation Oncology (ASTRO) have provided convincing evidence in favor of SBRT in patients with inoperable early-stage lung cancer and for patients with oligometastatic stage IV Non Small Cell Lung Cancer (NSCLC). RTOG 0236 is a phase II trial in which 59 frail, elderly patients with early stage, medically inoperable Stage I Non Small Cell Lung Cancer received SBRT in three fractions of 18 Gy (total of 54 Gy) over a period of 10 days to 2 weeks. The median age was 72 years and these patients had multiple comorbidities that precluded them from curative surgery. The primary end point was 2-year actuarial primary tumor control. Secondary end points included Disease Free Survival (i.e., primary tumor, involved lobe, regional, and disseminated recurrence), treatment-related toxicity and Overall Survival. At 5 years, the Disease Free Survival and Overall Survival were 26% and 40%, respectively and the median Overall Survival was 4 years. The 5-year primary tumor and involved lobe (local) failure rate was 20%, local-regional failure rate was 38% and disseminated failure rate was 31%. In a second study, Ashworth and colleagues reported the individual patient data meta-analysis, which included 757 patients diagnosed with stage IV NSCLC at 20 cancer centers worldwide. All patients had 1-5 synchronous or metachronous metastases treated with surgical metastectomy, SBRT, or radical external beam radiation therapy and the primary tumor was treated aggressively with a curative intent. The 1-year Overall Survival (OS) was 70.2% and 5-year Overall Survival was 29.4%. The authors were able to develop a risk stratification model for survival, to help identify which patients would be the best candidates for SBRT or surgery. They noted that patients with metachronous metastases had a 5-year Overall Survival of 48% and were considered low risk, those with synchronous metastases and negative nodes had a 5-year OS of 36% and were considered intermediate risk and patients with synchronous metastases and positive nodes were considered high risk and had a 5-year overall survival of 14%.

Taken together, these two studies have demonstrated that SBRT improves Overall Survival in elderly frail patients with medically inoperable early stage Lung Cancer and SBRT also improves Overall survival in patients Stage IV Non Small Cell Lung Cancer, with metachronous metastases without nodal involvement. A multidisciplinary team approach is strongly recommended, as treatment decisions are made for the latter group.

1)Long-term Results of RTOG 0236: A Phase II Trial of Stereotactic Body Radiation Therapy (SBRT) in the Treatment of Patients with Medically Inoperable Stage I Non-Small Cell Lung Cancer. Timmerman RD, Hu C, Michalski J, et al. DOI:http://dx.doi.org/10.1016/j.ijrobp.2014.05.135

2)An Individual Patient Data Meta-Analysis of Outcomes and Prognostic Factors After Treatment of Oligometastatic Non-Small Cell Lung Cancer. Ashworth A, Senan S, Palma DA, et al. DOI: http://dx.doi.org/10.1016/j.ijrobp.2014.08.028

Late Breaking Abstract – ASCO 2015 Elective Neck Dissection Improves Overall Survival and Disease Free Survival in Early Oral Cavity Cancers

SUMMARY: The American Cancer Society estimates that approximately 39,500 individuals will be diagnosed with oral cavity and oropharyngeal cancer in the United States in 2015 and about 7,500 will die of the disease. These cancers are more than twice as common in men as in women and tobacco and alcohol use are among the strongest risk factors. Routinely screening for oral mucosal lesions can improve survival in this patient group. The primary treatment of oral cavity squamous cell carcinoma is complete surgical resection with tumor free margins. Surgical management of the neck in patients with early stage oral cancers has remained unclear, with regards to the benefit of ipsilateral Elective Neck Dissection (END) at the time of primary surgery following diagnosis versus Therapeutic Neck Dissection (TND) after nodal relapse in the neck. To address this question, the authors conducted a prospective, randomized, controlled trial between 2004 and 2014, in which 596 treatment naïve patients with invasive squamous cell carcinoma of the oral cavity (tongue-85%, buccal mucosa-14%, floor of the mouth-1%) were enrolled and randomized to 1:1 to Elective Neck Dissection (END) or Therapeutic Neck Dissection (TND) following primary oral surgery. Patients had T1 (2 cm or less) or T2 (more than 2 cm and less than 4 cm) tumors that was lateralized to one side of the midline and were amenable to oral excision with adequate margins. Elective Neck Dissection (END) consisted of removal of submandibular (level 1), upper jugular (level 2)and midjugular (level 3) lymph nodes, with lower jugular (level 4) and posterior triangle (level 5) lymph nodes removed only if any of the lymph nodes in the first three levels showed intraoperative metastatic disease. Therapeutic Neck Dissection (TND) consisted of modified neck dissection (level 1-5) at the time of nodal relapse. All patients with high risk disease received adjuvant radiotherapy. The Primary end point was Overall Survival and Secondary end point was Disease Free Survival.

This publication summarizes the outcomes for the first 500 patients (245 in the END group and 255 in the TND group), following a median follow-up of 39 months. The 3 year Overall Survival was significantly higher in the Elective Neck Dissection group compared with the Therapeutic Neck Dissection group (80.0% vs. 67.5%, HR=0.63; P=0.01). The three year Disease Free Survival was also significantly higher in the END arm compared with TND (69.5% vs 45.9%, HR=0.45; P<0.001). The authors concluded that Elective Neck Dissection in patients with early stage oral squamous cell carcinoma resulted in 37% reduction in mortality risk as well as significantly high Disease Free Survival rates with a 55% reduction in the risk of disease recurrence. END should therefore be considered a standard treatment option. Elective versus Therapeutic Neck Dissection in Node-Negative Oral Cancer. D’Cruz AK, Vaish R, Kapre N, et al. N Engl J Med 2015; 373:521-529