PDCD1 Polymorphisms May Predict Response to Anti-PD-1 Blockade in Patients With Metastatic Melanoma

A significant number of patients (pts) with metastatic melanoma do not respond to anti-programmed cell death 1 (PD1) therapies. Identifying predictive biomarkers therefore remains an urgent need. We retrospectively analyzed plasma DNA of pts with advanced melanoma treated with PD-1 antibodies, nivolumab or pembrolizumab, for five PD-1 genotype single nucleotide polymorphisms (SNPs): PD1.1 (rs36084323, G>A), PD1.3 (rs11568821, G>A), PD1.5 (rs2227981, C>T) PD1.6 (rs10204225, G>A) and PD1.9 (rs2227982, C>T). Clinico-pathological and treatment parameters were collected, and presence of SNPs correlated with response, progression free survival (PFS) and overall survival (OS). 115 patients were identified with a median follow up of 18.7 months (range 0.26 – 52.0 months). All were Caucasian; 27% BRAF V600 mutation positive. At PD-1 antibody commencement, 36% were treatment-naïve and 52% had prior ipilimumab. The overall response rate was 43%, 19% achieving a complete response. Overall median PFS was 11.0 months (95% CI 5.4 - 17.3) and median OS was 31.1 months (95% CI 23.2 - NA). Patients with the G/G genotype had more complete responses than with A/G genotype (16.5% vs. 2.6% respectively) and the G allele of PD1.3 rs11568821 was significantly associated with a longer median PFS than the AG allele, 14.1 vs. 7.0 months compared to the A allele (p=0.04; 95% CI 0.14 – 0.94). No significant association between the remaining SNPs and responses, PFS or OS were observed. Despite limitations in sample size, this is the first study to demonstrate an association of a germline PD-1 polymorphism and PFS in response to anti-PD-1 therapy in pts with metastatic melanoma. Extrinsic factors like host germline polymorphisms should be considered with tumor intrinsic factors as predictive biomarkers for immune checkpoint regulators

Cholecystitis after yttrium-90 resin microsphere radioembolization treatment: Clinical and pathologic findings

Radioembolization with yttrium microspheres is an established therapeutic modality for primary and secondary hepatic malignancies, with studies demonstrating improved overall survival. There remains a paucity of data on cholecystitis as a complication of radioembolization. We describe a small series of patients who developed cholecystitis as a result of radioembolization. Patients who had developed cholecystitis as a complication of radioembolization in our institution between 2001 and 2012 were retrospectively reviewed. Patient demographics, cancer details including treatment history, and procedural details of radioembolization and complications of cholecystitis were collected. Of 74 patients who underwent radioembolization using yttrium-90emitting microspheres, four (5.4%) presented with acute cholecystitis as a result of their treatment. All patients presented over 4 weeks following radioembolization and did not settle with conservative treatment. At surgery, the gallbladder was fibrotic and contracted in all cases making surgery difficult. The incidence of symptomatic radiation cholecystitis after radioembolization is low, and prophylactic cholecystectomy is not routinely recommended for patients undergoing radioembolization. Radiation cholecystitis should be suspected in patients presenting with symptoms of biliary colic or cholecystitis following radioembolization. Early cholecystectomy can be considered in patients undergoing surgery for other indications, especially in high-risk surgical patients in whom there is a high likelihood of radioembolization in the future as they do not respond to conservative treatment

Regorafenib-induced hyperammonemic encephalopathy

What is known and objective Regorafenib improves progression-free survival as a late-line treatment for patients with metastatic gastrointestinal stromal tumour (GIST). As a multitargeted tyrosine kinase inhibitor (TKI), the expected adverse events of regorafenib are similar to those reported with imatinib, sunitinib or sorafenib. We report the first case of hyperammonemic encephalopathy related to regorafenib in a patient with metastatic GIST. Case summary A 61-year-old man maintained on regorafenib for metastatic GIST presented with acute confusion. Discontinuation of regorafenib led to complete resolution of confusion, which later recurred with hyperammonemia on recommencing regorafenib. Cessation of regorafenib and normalization of hyperammonemia then resulted in resolution of confusion. What is new and conclusions Regorafenib withdrawal and recommencement had influenced the confusional state and hyperammonemia in this patient. There is a probable relationship between regorafenib and metabolic encephalopathy. There are case reports of similar encephalopathy thought to be induced by other multitargeted TKI, and, as such, a class effect could be postulated

Multicellular Effects of STAT3 in Non-small Cell Lung Cancer: Mechanistic Insights and Therapeutic Opportunities

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and accounts for 85% of lung cancer cases. Aberrant activation of the Signal Transducer and Activator of Transcription 3 (STAT3) is frequently observed in NSCLC and is associated with a poor prognosis. Pre-clinical studies have revealed an unequivocal role for tumor cell-intrinsic and extrinsic STAT3 signaling in NSCLC by promoting angiogenesis, cell survival, cancer cell stemness, drug resistance, and evasion of anti-tumor immunity. Several STAT3-targeting strategies have also been investigated in pre-clinical models, and include preventing upstream receptor/ligand interactions, promoting the degradation of STAT3 mRNA, and interfering with STAT3 DNA binding. In this review, we discuss the molecular and immunological mechanisms by which persistent STAT3 activation promotes NSCLC development, and the utility of STAT3 as a prognostic and predictive biomarker in NSCLC. We also provide a comprehensive update of STAT3-targeting therapies that are currently undergoing clinical evaluation, and discuss the challenges associated with these treatment modalities in human patients

Cholecystitis after yttrium-90 resin microsphere radioembolization treatment: Clinical and pathologic findings

Background: Radioembolization with yttrium microspheres is an established therapeutic modality for primary and secondary hepatic malignancies, with studies demonstrating improved overall survival. There remains a paucity of data on cholecystitis as a complication of radioembolization. We describe a small series of patients who developed cholecystitis as a result of radioembolization. Methods: Patients who had developed cholecystitis as a complication of radioembolization in our institution between 2001 and 2012 were retrospectively reviewed. Patient demographics, cancer details including treatment history, and procedural details of radioembolization and complications of cholecystitis were collected. Results: Of 74 patients who underwent radioembolization using yttrium-90emitting microspheres, four (5.4%) presented with acute cholecystitis as a result of their treatment. All patients presented over 4 weeks following radioembolization and did not settle with conservative treatment. At surgery, the gallbladder was fibrotic and contracted in all cases making surgery difficult. Conclusion: The incidence of symptomatic radiation cholecystitis after radioembolization is low, and prophylactic cholecystectomy is not routinely recommended for patients undergoing radioembolization. Radiation cholecystitis should be suspected in patients presenting with symptoms of biliary colic or cholecystitis following radioembolization. Early cholecystectomy can be considered in patients undergoing surgery for other indications, especially in high-risk surgical patients in whom there is a high likelihood of radioembolization in the future as they do not respond to conservative treatment

Cholecystitis after yttrium-90 resin microsphere radioembolization treatment: Clinical and pathologic findings

Background: Radioembolization with yttrium microspheres is an established therapeutic modality for primary and secondary hepatic malignancies, with studies demonstrating improved overall survival. There remains a paucity of data on cholecystitis as a complication of radioembolization. We describe a small series of patients who developed cholecystitis as a result of radioembolization. Methods: Patients who had developed cholecystitis as a complication of radioembolization in our institution between 2001 and 2012 were retrospectively reviewed. Patient demographics, cancer details including treatment history, and procedural details of radioembolization and complications of cholecystitis were collected. Results: Of 74 patients who underwent radioembolization using yttrium-90emitting microspheres, four (5.4%) presented with acute cholecystitis as a result of their treatment. All patients presented over 4 weeks following radioembolization and did not settle with conservative treatment. At surgery, the gallbladder was fibrotic and contracted in all cases making surgery difficult. Conclusion: The incidence of symptomatic radiation cholecystitis after radioembolization is low, and prophylactic cholecystectomy is not routinely recommended for patients undergoing radioembolization. Radiation cholecystitis should be suspected in patients presenting with symptoms of biliary colic or cholecystitis following radioembolization. Early cholecystectomy can be considered in patients undergoing surgery for other indications, especially in high-risk surgical patients in whom there is a high likelihood of radioembolization in the future as they do not respond to conservative treatment

Radiolabeled Antibodies for Cancer Imaging and Therapy

Radioimmunoconjugates consist of a monoclonal antibody (mAb) linked to a radionuclide. Radioimmunoconjugates as theranostics tools have been in development with success, particularly in hematological malignancies, leading to approval by the US Food and Drug Administration (FDA) for the treatment of non-Hodgkin’s lymphoma. Radioimmunotherapy (RIT) allows for reduced toxicity compared to conventional radiation therapy and enhances the efficacy of mAbs. In addition, using radiolabeled mAbs with imaging methods provides critical information on the pharmacokinetics and pharmacodynamics of therapeutic agents with direct relevance to the optimization of the dose and dosing schedule, real-time antigen quantitation, antigen heterogeneity, and dynamic antigen changes. All of these parameters are critical in predicting treatment responses and identifying patients who are most likely to benefit from treatment. Historically, RITs have been less effective in solid tumors; however, several strategies are being investigated to improve their therapeutic index, including targeting patients with minimal disease burden; using pre-targeting strategies, newer radionuclides, and improved labeling techniques; and using combined modalities and locoregional application. This review provides an overview of the radiolabeled intact antibodies currently in clinical use and those in development

Antibody–Drug Conjugates for Cancer Therapy

Antibody–drug conjugates (ADCs) take advantage of the specificity of a monoclonal antibody to deliver a linked cytotoxic agent directly into a tumour cell. The development of these compounds provides exciting opportunities for improvements in patient care. Here, we review the key issues impacting on the clinical success of ADCs in cancer therapy. Like many other developing therapeutic classes, there remain challenges in the design and optimisation of these compounds. As the clinical applications for ADCs continue to expand, key strategies to improve patient outcomes include better patient selection for treatment and the identification of mechanisms of therapy resistance