Combination of Immunotherapy and Radiation Therapy in Gastrointestinal Cancers: An Appraisal of the Current Literature and Ongoing Research.

Oncological outcomes are improving in gastrointestinal cancer with advancements in systemic therapies, and there is notable potential in combining immunotherapy and radiation therapy (RT) to allow for further improvements. Various preclinical and early phase II studies have shown promising synergy with immunotherapy and RT in gastrointestinal cancer. A few recent phase III studies have shown improved survival with the addition of immunotherapy to standard treatment for gastrointestinal cancer. The timing, duration, sequencing, and integration with other anti-cancer treatments are still areas of ongoing research. We have reviewed the published and ongoing studies of the combinations of immunotherapy and RT in gastrointestinal cancers.

A phase I trial of riluzole and sorafenib in patients with advanced solid tumors: CTEP #8850.

BACKGROUND: Overexpression of metabotropic glutamate receptor 1 (GRM1) has been implicated in the pathogenesis of multiple cancers. Riluzole, an inhibitor of glutamate release, showed synergistic antitumor activity in combination with the multi-kinase inhibitor sorafenib in preclinical models. This phase I trial identified the toxicity profile, dose-limiting toxicities, maximum tolerated dose (MTD), and pharmacokinetic and pharmacodynamic properties of riluzole combined with sorafenib in patients with advanced cancers. PATIENTS AND METHODS: Patients with refractory solid tumors were enrolled utilizing a 3+3 dose-escalation design. Riluzole was given at 100 mg PO BID in combination with sorafenib, beginning at 200 mg PO daily and escalating in 200 mg increments per level in 28-day cycles. Restaging evaluations were performed every 2 cycles. RESULTS: 35 patients were enrolled over 4 dose levels. The MTD was declared at dose level 3 (riluzole: 100 mg PO BID; sorafenib: 400 mg AM/200 mg PM). Pharmacokinetic analyses did not reveal definitive evidence of drug-drug interactions. Consistent decreases in phospho-forms of ERK and AKT in tumor tissue analyses with accompanying decrease in GRM1 expression and increase in pro-apoptotic BIM suggest target engagement by the combination. Best responses included a partial response in 1 (2.9%) patient with pancreatic acinar cell carcinoma with a KANK4-RAF1 fusion, and stable disease in 11 (36%) patients. CONCLUSION: Combination therapy with riluzole and sorafenib was safe and tolerable in patients with advanced solid tumors. The partial response in a patient with a RAF1 fusion suggests that further exploration in a genomically selected cohort may be warranted.

Disease Control Achieved Using Atezolizumab + Bevacizumab in a Patient With Sarcomatoid Hepatocellular Carcinoma (SHCC), a Rare Variant Excluded From the IMbrave150 Trial.

Sarcomatoid hepatocellular carcinoma (SHCC) is a rare variant of liver cancer that lacks treatment options. The IMbrave trail demonstrated the efficacy of atezolizumab and bevacizumab (A + B) in patients with unresectable hepatocellular carcinoma but excluded patients with sarcomatoid variants. Herein, we describe a case of disease control achieved using the IMbrave regimen in a patient with sarcomatoid hepatocellular carcinoma.

Delayed cytokine release syndrome after neoadjuvant nivolumab: a case report and literature review.

Aim: Cytokine release syndrome (CRS) is an infrequently described immune-related adverse event of checkpoint inhibitors (CPI). CPI-induced CRS typically presents with fevers, hemodynamic instability and organ dysfunction within 2 weeks of the last treatment cycle. Case study: We report an unusual case of delayed and severe CRS occurring postoperatively in a patient with hepatic-limited metastatic colorectal cancer who received neoadjuvant immunotherapy. After a negative workup for alternative causes, he received prolonged corticosteroid treatment with symptom resolution. Conclusion: CPI-induced CRS can mimic sepsis and clinicians should maintain a high-index of suspicion to diagnose this immune-related adverse event early and initiate appropriate treatment. As use of perioperative immunotherapy increases, the potential role of surgery to trigger CRS in this case warrants further investigation.

Lay abstract Aim: Cytokine release syndrome (CRS) is a rare but potentially serious side effect of a class of immunotherapy drugs called checkpoint inhibitors (CPI). CRS typically presents with fevers and low blood pressure and can cause damage to organs including the kidneys and liver. Case study: We report an unusual case of severe CRS occurring after surgery in a patient who had received prior CPI therapy. After a thorough evaluation for alternative causes, he was diagnosed with CRS and treated successfully with steroids. Conclusion: It is important for medical providers to consider this potential side effect when treating patients with CPI. Further research is needed to clarify the role of surgery in CPI-induced CRS.

Outcomes of patients with borderline resectable and resectable pancreatic adenocarcinoma treated with neoadjuvant three-week course chemoradiotherapy using capecitabine-based versus gemcitabine-based concurrent chemotherapy.

BACKGROUND: Neoadjuvant chemoradiotherapy can provide downstaging and improve margin negativity for borderline resectable and resectable pancreatic adenocarcinoma [(B)RPC]. Little is known about the relative efficacy of capecitabine (CAPE)-based vs. gemcitabine (GEM)-based 3-week chemoradiation (3WCRT) with 36 Gy in 15 fractions. This study aimed to compare the odds of achieving surgical resection, time to progression (TTP), and overall survival (OS) of patients treated with 3WCRT with concurrent CAPE versus GEM. METHODS: A retrospective cohort study was conducted, examining medical records from a single center for patients with (B)RPC treated with 3WCRT between 1/2009-12/2020. Odd ratios (OR) of achieving surgical resection were estimated using logistic regression for univariable and multivariable analyses. Median TTP (mTTP) and median OS (mOS) were estimated using the Kaplan-Meier method. Cox proportional hazards analysis was conducted to estimate hazard ratios (HR) of progression and survival in univariable and multivariable analyses. RESULTS: Thirty-one patients were included in the analysis. Twenty-two (71%) patients were treated with CAPE, while 9 (29%) were treated with GEM. All patients in the GEM group were borderline resectable, vs. 18 (82%) patients in the CAPE group, P=0.30. Nineteen (86%) patients in the CAPE group were treated with neoadjuvant FOLFIRINOX, vs. 4 (44%) patients in the GEM group, P=0.03. The CAPE group had higher odds of achieving surgical resection [OR =9.33; 95% confidence interval (CI): 1.50-58.20]. Adjusting for covariates, the odds of achieving surgical resection were still statistically higher in the CAPE group vs. the GEM group (OR =25.34; 95% CI: 1.14-563.72). The CAPE group had superior mTTP compared to the GEM group (15.4 months, 95% CI: 4.9-71.1 vs. 4.0 months, 95% CI: 0.4-14.5; P=0.01), corresponding to a hazard ratio of 0.33 (95% CI: 0.14-0.81). Adjusting for covariates this effect persisted; the adjusted hazard ratio (AHR) for progression was 0.24 (95% CI: 0.08-0.77). Cox proportional hazards analysis also demonstrated that the CAPE group had superior OS compared to the GEM group in unadjusted (HR =0.13; 95% CI: 0.04-0.40) and adjusted models (HR =0.13, 95% CI: 0.03-0.52). CONCLUSIONS: For neoadjuvant 3WCRT, this hypothesis-generating study suggests concurrent CAPE may be a more effective radiosensitizer than GEM for patients with (B)RPC.

Rethinking the Role of Radiation Therapy in the Treatment of Unresectable Hepatocellular Carcinoma: A Data Driven Treatment Algorithm for Optimizing Outcomes.

Hepatocellular carcinoma (HCC) is the second most common cause of cancer death worldwide, with a majority of HCC patients not suitable for curative therapies. Approximately 70% of initially diagnosed patients cannot undergo surgical resection or transplantation due to locally advanced disease, poor liver function/underlying cirrhosis, or additional comorbidities. Local therapeutic options for patients with unresectable HCC, who are not suitable for thermal ablation, include transarterial embolization (bland, chemoembolization, radioembolization) and/or external beam radiation therapy (EBRT). Regarding EBRT specifically, technological advancements provide a means for safe and effective radiotherapy delivery in a wide spectrum of HCC patients. In multiple prospective studies, EBRT delivery in a variety of different fractionation schemes or in combination with transcatheter arterial chemoembolization (TACE) demonstrate improved outcomes, particularly with combination therapy. The Barcelona Clinic Liver Cancer classification provides a framework for treatment selection; however, given the growing complexity of treatment strategies, this classification system tends to simplify decision-making. In this review, we discuss the current literature regarding unresectable HCC and propose a modified treatment algorithm that emphasizes the role of radiation therapy for Child-Pugh score A or B patients with ≤3 nodules measuring >3 cm, multinodular disease or portal venous thrombosis.

Adjuvant therapeutic strategies for resectable pancreatic adenocarcinoma.

Of all patients diagnosed with pancreatic adenocarcinoma, only 15-20% present with resectable disease. Despite curative-intent resection, the prognosis remains poor with the majority of patients recurring, prompting the need for adjuvant therapy. Historical data support the use of adjuvant 5-fluorouracil (5-FU) or gemcitabine, but recent data suggest either gemcitabine plus capecitabine or modified FOLFIRINOX can improve overall survival when compared to gemcitabine alone. The use of adjuvant chemoradiation therapy remains controversial, primarily due to limitations in study design and mixed results of historical trials. The ongoing Radiation Therapy Oncology Group (RTOG)-0848 trial hopes to further define the role of adjuvant chemoradiation therapy. Intraoperative radiation therapy (IORT) and adjuvant immunotherapy represent additional possibilities to improve outcomes, but evidence supporting their use is limited. This article reviews adjuvant therapeutic strategies for resectable pancreatic adenocarcinoma, including chemotherapy, chemoradiation therapy, IORT and immunotherapy.

Biomarkers for Immunotherapy: Current Developments and Challenges.

Immunotherapy has revolutionized cancer therapy and has been named the cancer advance of the year for 2016. Checkpoint inhibitors have demonstrated unprecedented rates of durable responses in some of the most difficult-to-treat cancers; however, many treated patients do not respond, and the potential for serious side effects exists. There is a growing need to identify biomarkers that will improve the selection of patients who will best respond to therapy, further elucidate drug mechanisms of action, and help tailor therapy regimens. Biomarkers are being explored at the soluble, cellular, and genomic levels, and examples in immunotherapy include serum proteins, tumor-specific receptor expression patterns, factors in the tumor microenvironment, circulating immune and tumor cells, and host genomic factors. The search for reliable biomarkers is limited by our incomplete understanding of how immunotherapies modify the already complex immune response to cancer, as well as the contribution of immuno-editing to a dynamic and inducible tumor microenvironment and immune milieu. Furthermore, there has been little extension of any candidate assay into large, prospective studies, and the lack of standardization in measurement and interpretation restricts their validity. Both tumor-infiltrating lymphocytes and PD-L1 expression within the tumor microenvironment have been recognized as having both prognostic and predictive value for patients treated with immunotherapy. Alternately, a larger panel of gene signatures, chemokines, and other factors that correlate with response has been proposed. In this article, we will explore the status of current biomarker candidates.

Mucosal Melanoma: Epidemiology, Biology and Treatment.

Mucosal melanoma is an exceedingly rare variant of cutaneous melanoma that, due to its rarity, is poorly described and infrequently studied. Primary sites of origin include the head and neck, anorectum and vulvovaginal regions. It is uniquely different from cutaneous melanoma with respect to epidemiology, etiology, pathogenesis and prognosis. The etiology and pathogenesis remain unclear. Unlike cutaneous melanoma, exposure to UV light is not an apparent risk factor. Furthermore, distinct molecular features including a lower incidence of BRAF oncogene mutations but a higher incidence of KIT oncogene mutations suggest divergent genetic etiologies. Mucosal melanomas generally present at a later stage, are more aggressive and carry a worse prognosis regardless of the stage at diagnosis. Establishing standardized treatment guidelines has been challenging due to the rarity of the disease. Early detection provides the best chance at survival but is often difficult due to anatomic location. Surgery remains the primary therapeutic intervention if complete resection is technically feasible given the anatomic location. Radiotherapy may be used to achieve local control when resection is not feasible, or adjuvantly to enhance locoregional control, but most studies have failed to demonstrate an improvement in overall survival. There are no consensus guidelines on the optimal systemic therapy, and regimens are often extrapolated from data based on therapies used to treat advanced cutaneous melanoma. Clinical trials, particularly utilizing newer targeted therapies and immunotherapies, are investigating novel treatment approaches.

When Benign Tumors Mimic Malignancies: A Case of Lymphangiomatosis Masquerading as Metastatic Disease.

Lymphangiomatosis, a rare disorder of the lymphatic system characterized by the abnormal proliferation of lymphatic vessels, is a typically benign disorder that at times can exhibit invasive or malignant behavior. While generally considered a diagnosis of childhood, in adults the majority of cases are asymptomatic and found incidentally. Rarely, lymphatic overgrowth can occur, causing growth of lesions on imaging mimicking a metastatic process and occasionally, resulting in substantial morbidity and mortality. Here, we present such a case of lymphangiomatosis with multi-organ system involvement in liver, bone, and spleen. In addition to details of the clinical presentation and the pathologic review which led to the diagnosis, we describe our use of the tyrosine kinase inhibitor pazopanib, which may cause stabilization of lymphangiomatosis through blockade of vascular endothelial growth factor (VEGF) signaling, for systemic treatment in this unusual case.