No abstract

The success of immune checkpoint inhibitors (ICIs) in an increasing range of heavily mutated tumor types such as melanoma has culminated in their exploration in different subsets of patients with metastatic colorectal cancer (mCRC). As a result of their dramatic and durable response rates in patients with chemorefractory, mismatch repair-deficient-microsatellite instability-high (dMMR-MSI-H) mCRC, ICIs have become potential alternatives to classical systemic therapies. The anti-programmed death-1 (PD-1) agents, Pembrolizumab and Nivolumab, have been granted FDA approval for this subset of patients. Unfortunately, however, not all CRC cases with the dMMR-MSI-H phenotype respond well to ICIs, and ongoing studies are currently exploring biomarkers that can predict good response to them. Another challenge lies in developing novel treatment strategies for the subset of patients with the mismatch repair-proficient-microsatellite instability-low (pMMR-MSI-L) phenotype that comprises 95% of all mCRC cases in whom treatment with currently approved ICIs has been largely unsuccessful. Approaches aiming at overcoming the resistance of tumors in this subset of patients are being developed including combining different checkpoint inhibitors with either chemotherapy, anti-angiogenic agents, cancer vaccines, adoptive cell transfer (ACT), or bispecific T-cell (BTC) antibodies. This review describes the rationale behind using immunotherapeutics in CRC. It sheds light on the progress made in the use of immunotherapy in the treatment of patients with dMMR-MSI-H CRC. It also discusses emerging approaches and proposes potential strategies for targeting the immune microenvironment in patients with pMMR-MSI-L CRC tumors in an attempt to complement immune checkpoint inhibition.

Background Neoadjuvant chemotherapy and short-course radiotherapy followed by resection has been gaining recognition in the treatment of rectal cancer. Avelumab is a fully human immunoglobulin that binds Programmed Death-Ligand 1 (PD-L1) and prevents the suppression of the cytotoxic T cell immune response. This phase II trial evaluates the safety and pathologic response rate of short-course radiation followed by 6 cycles of mFOLFOX6 with avelumab in patients with locally advanced rectal cancer (LARC). Methods This study is prospective single-arm, multicenter phase II trial adopting Simon’s two-stage. Short-course radiation is given over 5 fractions to a total dose of 25 Gy. mFOLFOX6 plus avelumab (10 mg/kg) are given every 2 weeks for 6 cycles. Total mesorectal excision is performed 3–4 weeks after the last cycle of avelumab. Follow up after surgery is done every 3 months to a total of 36 months. Adverse event data collection is recorded at every visit. Results 13 out of 44 patients with LARC were enrolled in the first stage of the study (30% from total sample size). All patients met the inclusion criteria and received the full short-course radiation course followed by 6 cycles of mFOLFOX6 plus avelumab. 12 out of the 13 patients completed TME while one patient had progression of disease and was dropped out of the study. The sample consisted of 9 (69%) males and 4 (31%) females with median age of 62 (33–73) years. The first interim analysis revealed that 3 (25%) patients achieved pathologic complete response (pCR) (tumor regression grade, TRG 0) out of 12. While 3 (25%) patients had near pCR with TRG 1. In total, 6 out of 12 patients (50%) had a major pathologic response. All patients were found to be MMR proficient. The protocol regimen was well tolerated with no serious adverse events of grade 4 reported. Conclusion In patients with LARC, neoadjuvant radiation followed by mFOLFOX6 with avelumab is safe with a promising pathologic response rate. Trial Registration Number and Date of Registration ClinicalTrials.gov NCT03503630, April 20, 2018. https://clinicaltrials.gov/ct2/show/NCT03503630?term=NCT03503630&draw=2&rank=1.

Treatment recommendations for primary liver malignancies, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), are complex and require a multidisciplinary approach. Despite surgical options that are potentially curative, options for nonsurgical candidates include systemic therapy, radiotherapy (RT), transarterial chemoembolization (TACE), and radiofrequency ablation (RFA). Stereotactic Body Radiation Therapy (SBRT) is now in routine use for the treatment of lung cancer, and there is growing evidence supporting its use in liver tumors. SBRT has the advantage of delivering ablative radiation doses in a limited number of fractions while minimizing the risk of radiation-induced liver disease (RILD) through highly conformal treatment plans. It should be considered in a multidisciplinary setting for the management of patients with unresectable, locally advanced primary liver malignancies and limited treatment options. Recently, the combination of immunotherapy with SBRT has been proposed to improve antitumor effects through engaging the immune system. This review aims at shedding light on the novel concept of the combination strategy of immune-radiotherapy in liver tumors by exploring the evidence surrounding the use of SBRT and immunotherapy for the treatment of HCC and CCA.

Background Current standard practice for locally advanced rectal cancer (LARC) entails a multidisciplinary approach that includes preoperative chemoradiotherapy, followed by total mesorectal excision, and then adjuvant chemotherapy. The latter has been accompanied by low compliance rates and no survival benefit in phase III randomized trials, so the strategy of administering neoadjuvant, rather than adjuvant, chemotherapy has been adapted by many trials, with improvement in pathologic complete response. Induction chemotherapy with oxaliplatin has been shown to have increased efficacy in rectal cancer, while short-course radiation therapy with consolidation chemotherapy increased short-term overall survival rate and decreased toxicity levels, making it cheaper and more convenient than long-course radiation therapy. This led to recognition of total neoadjuvant therapy as a valid treatment approach in many guidelines despite limited available survival data. With the upregulation (PDL-1) expression in rectal tumors after radiotherapy and the increased use of in malignant melanoma, the novel approach of combining immunotherapy with chemotherapy after radiation may have a role in further increasing pCR and improving overall outcomes in rectal cancer. Methods The study is an open label single arm multi- center phase II trial. Forty-four recruited LARC patients will receive 5Gy x 5fractions of SCRT, followed by 6 cycles of mFOLFOX-6 plus avelumab, before TME is performed. The hypothesis is that the addition of avelumab to mFOLFOX-6, administered following SCRT, will improve pCR and overall outcomes. The primary outcome measure is the proportion of patients who achieve a pCR, defined as no viable tumor cells on the excised specimen. Secondary objectives are to evaluate 3-year progression-free survival, tumor response to treatment (tumor regression grades 0 & 1), density of tumor-infiltrating lymphocytes, correlation of baseline Immunoscore with pCR rates and changes in PD-L1 expression. Discussion Recent studies show an increase in PD-L1 expression and density of CD8+ TILs after CRT in rectal cancer patients, implying a potential role for combinatory strategies using PD-L1- and programmed-death- 1 inhibiting drugs. We aim through this study to evaluate pCR following SCRT, followed by mFOLFOX-6 with avelumab, and then TME procedure in patients with LARC. Trial registration Trial Registration Number and Date of Registration: ClinicalTrials.gov NCT03503630, April 20, 2018.

Background Patients with liver cirrhosis have altered hepatic synthetic functions which theoretically result in reduced levels of pro-and anti-coagulant factors as well as thrombocytopenia. Initially, cirrhotic patients were thought to be at an increased risk of bleeding and a reduced risk of thrombosis. Several studies have recently reported an increased occurrence of venous thromboembolism (VTE) in cirrhotic patients. In this study, we aimed to assess the current practice of deep venous thrombosis (DVT) prophylaxis, the incidence and predictors of VTE, and the associated bleeding sequelae in patients with liver cirrhosis. Methods A retrospective cohort study was performed. We included all adult patients with a diagnosis of liver cirrhosis from January 2010 to June 2019 admitted to the hospital. Our cohort patients were divided into two groups, cirrhotic patients with pharmacological VTE prophylaxis and those with mechanical or no VTE prophylaxis. Results We included 601 cirrhotic patients in our study. The incidence of VTE occurring within the first 6 months of their admission was 1.5%. Seven patients (1.49%) developed VTE with the majority being DVTs while not on pharmacologic prophylaxis, and two patients developed VTE despite being on pharmacologic prophylaxis; however, there was no statistical difference. Alcohol use was the most common underlying cause of liver cirrhosis (40.4%), followed by chronic hepatitis C (21.1%), and nonalcoholic steatohepatitis (11.3%). Out of the 601 patients included, 69 patients received neither pharmacologic nor mechanical VTE prophylactic agent (11.48%), while the remaining majority received either pharmacological or mechanical prophylaxis (88.52%). Conclusions Our study did not show a statistically significant association between the use of pharmacological VTE prophylactic agents and a reduction in the risk of VTE in cirrhotic patients. The rates of usage of DVT prophylactic agents among our Northwell hospitals during the study period appeared to be no longer suboptimal when compared to prior studies. Low albumin appears to be a predictor factor to develop VTE. There was a statistically significant increase in bleeding risk and transfusion requirement in cirrhotic patients receiving no pharmacological VTE prophylactic agents. Further prospective trials are needed to shed more light on this subject and identify the group of cirrhotic patients who could safely benefit from pharmacologic VTE prophylaxis.

Chronic liver disease (CLD) and its complications constitute a significant cause of mortality and morbidity worldwide. Most deaths are secondary to the decompensation of cirrhosis and evolution of portal hypertension (PHTN). Since disease progression reversal is hardly attainable after decompensated cirrhosis develops, it is essential to intervene early with a therapeutic agent or regimen that could prevent or slow disease evolution. Thus far, there has been no agreed-upon medication to help in the fight against the development of cirrhosis or its decompensation. While early data depicted statins as harmful agents for the liver, current evidence from preclinical and clinical studies suggests that they might have positive impact on CLD. Low-quality evidence supports the fact that statins reduce mortality in CLD. Moderate-quality evidence suggests that statins reduce the risk of hepatic decompensation, variceal bleeding, and mortality, especially among patients with compensated cirrhosis. Combining this data with the long track-record of safety and tolerability of statins and their potential benefits in hepatocellular carcinoma (HCC) risk reduction, hepatologists might soon rely on statins to achieve better outcomes in their CLD and cirrhotic patients without significant additional costs. This review describes the rationale behind the use of statins in patients with CLD and cirrhosis. It sheds light on the current preclinical and clinical studies that reflect beneficial effects of the use of different types and doses of statins in the treatment of patients with different types and stages of CLD and cirrhosis. It also emphasizes the need for designing and developing additional large prospective interventional randomized control trials (RCTs) to better evaluate the association between statin exposure and the risk of fibrosis progression and development of cirrhosis in patients with non-cirrhotic CLDs, the risk of progression of PHTN in patients with cirrhosis, and the mortality rates in patients with cirrhotic or non-cirrhotic CLDs.

139 Background: Total neoadjuvant treatment (TNT) for locally advanced rectal cancer is becoming an accepted approach over the last few years with increasing pathologic complete response (pCR) and compliance of patients for chemotherapy in comparison with the current standard of care i.e., fluoropyrimidine based chemoradiation followed by surgery and adjuvant chemotherapy. Sequential use checkpoint inhibitors after radiation therapy (RT) has demonstrated synergistic effect in vivo leading to decrease in size of irradiated and non-irradiated secondary tumors outside the radiation field (abscopal effect). Methods: This is an investigator initiated; open-label, single-arm multicenter phase II study, adopting Simon’s two-stage aiming at evaluating the pCR rate and safety of using short-course radiation therapy (25 Grays in 5 fractions), followed by 6 cycles of mFOLFOX-6 plus Avelumab (anti PDL1), then total mesorectal excision(TME) in patients with locally-advanced, potentially resectable rectal adenocarcinoma. Results: 13 out of 44 patients were accrued from 20, July till 28, Dec 2018 in the first stage of the study (30% from total sample size). They all met the inclusion criteria and received full protocol treatment. 12 out of the 13 completed TME. 1 of the 13 had progression of disease, so surgery was aborted and patient was dropped out the study. The sample consisted of 9 (69%) males and 4 (31%) females with median age of 62 (33.0, 73.0) years. The first interim analysis revealed 3 patients (25%) achieved pCR (tumor regression grade: TRG = 0) out of 12 as compared to the historical control group with pCR of 16%. For the rest of the patients, 3 (25%) had major pathologic response rate (pRR) with TRG = 1 (< 10% viable cells is tumor bed).In total, 6 out of 12 patients (50%) had major pathologic response rate. As for safety, no serious adverse events of grade 3 and 4 were reported. Conclusions: Based on the first interim analysis results, incorporation of Avelumab and short course radiotherapy is tolerable in patients with locally advanced rectal cancer treated with TNT. The study will resume recruitment to reach the target accrual. Clinical trial information: NCT03503630.