Clinical outcomes and risk stratification in unresectable biliary tract cancers undergoing radiation therapy.

BACKGROUND: Biliary tract cancers (BTC) are rare and aggressive malignancies originating from intrahepatic and extrahepatic bile ducts and the gallbladder. Surgery is the only curative option, but due to late-stage diagnosis, is frequently not feasible, leaving chemotherapy as the primary treatment. Radiotherapy (RT) can be an effective alternative for patients with unresectable, non-metastatic BTC despite the generally poor prognosis and significant variability. To help manage patients with unresectable BTC who receive RT, we aimed to identify prognostic markers that could aid in predicting overall survival (OS). METHODS: A retrospective cohort study was conducted at the University of Pennsylvania, involving seventy-eight patients with unresectable BTC treated with definitive intent RT. Comprehensive demographic, clinical, and treatment-related data were extracted from the electronic medical records. Univariate and multivariate Cox regressions were employed to identify predictors of OS after RT. A biomarker model was developed for refined survival prediction. RESULTS: The cohort primarily comprised patients with good performance status without significant hepatic dysfunction at presentation. The predominant treatment approach involved hypofractionated RT or concurrent 5FU-based chemoRT. Median OS after RT was 12.3 months, and 20 patients (15.6%) experienced local progression with a median time of 30.1 months. Univariate and multivariate analyses identified CA19-9 (above median) and higher albumin-bilirubin (ALBI) grades at presentation as significant predictors of poor OS. Median OS after RT was 24 months for patients with no risk factors and 6.3 months for those with both. CONCLUSIONS: Our study demonstrates generally poor but significantly heterogeneous OS in patients with unresectable BTC treated with RT. We have developed a biomarker model based on CA19-9 and ALBI grade at presentation that can distinguish sub-populations with markedly diverse prognoses. This model can aid the clinical management of this challenging disease.

Proton radiation boosts the efficacy of mesothelin-targeting chimeric antigen receptor T cell therapy in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) represents a challenge in oncology, with limited treatment options for advanced-stage patients. Chimeric antigen receptor T cell (CAR T) therapy targeting mesothelin (MSLN) shows promise, but challenges such as the hostile immunosuppressive tumor microenvironment (TME) hinder its efficacy. This study explores the synergistic potential of combining proton radiation therapy (RT) with MSLN-targeting CAR T therapy in a syngeneic PDAC model. Proton RT significantly increased MSLN expression in tumor cells and caused a significant increase in CAR T cell infiltration into tumors. The combination therapy reshaped the immunosuppressive TME, promoting antitumorigenic M1 polarized macrophages and reducing myeloid-derived suppressor cells (MDSC). In a flank PDAC model, the combination therapy demonstrated superior attenuation of tumor growth and improved survival compared to individual treatments alone. In an orthotopic PDAC model treated with image-guided proton RT, tumor growth was significantly reduced in the combination group compared to the RT treatment alone. Further, the combination therapy induced an abscopal effect in a dual-flank tumor model, with increased serum interferon-γ levels and enhanced proliferation of extratumoral CAR T cells. In conclusion, combining proton RT with MSLN-targeting CAR T therapy proves effective in modulating the TME, enhancing CAR T cell trafficking, and exerting systemic antitumor effects. Thus, this combinatorial approach could present a promising strategy for improving outcomes in unresectable PDAC.

Start Early and See Inflammatory; Late, Nothing Save RAVE: How to Appreciate Radiation Proctitis as a Continuum.

Background and Aims: It has been recently proposed to change the nomenclature of "chronic radiation proctitis" (CRP) to "radiation-associated vascular ectasia" on the basis that signs of inflammation are rarely observed. We herein present data supporting the idea that inflammation is a critical step that initiates the process that culminates in the characteristic changes of CRP. Methods: In support of inflammation in the pathogenesis of CRP, we review the pertinent literature and publish our new results, including the role of amifostine treatment and proinflammatory factors (p38 MAP kinase, VEGF, and CEACAM1). Results: Immunohistochemistry from anterior rectal wall biopsies obtained in a prospective pilot study demonstrates that expression of VEGF and the downstream vascular effector CEACAM1 were elevated before radiotherapy and declined with time. We also show that MAP Kinase p38 expression usually precede the radiation. Fibrosis scores increase from baseline at 9 and 18 months, while vascular scores decrease at 18 months. Conclusion: The proposed new nomenclature should be held in obeyance until more supportive data are presented. Possibly, the best way to view CRP is as a continuum that may take one of three forms, inflammation-predominant, vasculopathy-predominant, or mixed.