Colorectal carcinogenesis in the Lynch syndromes and familial adenomatous polyposis: trigger events and downstream consequences.

Carcinogenesis encompasses processes that lead to increased mutation rates, enhanced cellular division (tumour growth), and invasive growth. Colorectal cancer (CRC) carcinogenesis in carriers of pathogenic APC (path_APC) and pathogenic mismatch repair gene (path_MMR) variants is initiated by a second hit affecting the corresponding wild-type allele. In path_APC carriers, second hits result in the development of multiple adenomas, with CRC typically emerging after an additional 20 years.

Prognostic Features and Potential for Immune Therapy in Metastatic Mismatch Repair-Deficient Colorectal Cancer: A Retrospective Analysis of a Large Consecutive Population-Based Patient Series.

Background: Immune checkpoint inhibition therapies have provided remarkable results in numerous metastatic cancers, including mismatch repair-deficient (dMMR) colorectal cancer (CRC). To evaluate the potential for PD-1 blockade therapy in a large population-based cohort, we analyzed the tumor microenvironment and reviewed the clinical data and actualized treatment of all dMMR CRCs in Central Finland province between 2000 and 2015.

Material And Methods: Of 1343 CRC patients, 171 dMMR tumors were identified through immunohistochemical screening.

Histological synovitis score in juvenile idiopathic arthritis and other pediatric synovial inflammatory conditions.

Objective: The Krenn's scoring is a system for histopathological grading of synovial inflammation, and in adults, useful in etiological grouping. The score has only rarely been used in pediatric samples. We aimed to assess the performance of the score in juvenile idiopathic arthritis and other pediatric synovial inflammatory processes in categorization of the disease and in finding characteristic pathological features.

The impact of preoperative treatments on the immune environment of rectal cancer.

To improve local disease control, the use of preoperative radiotherapy either alone or combined with chemotherapy has become standard practice in rectal cancer, but it is unclear how these treatments modify the antitumoral immune response. We aimed to evaluate tumor histopathologic features and the prognostic effect of host immune response in rectal cancer with variable treatment modalities. Ninety-five rectal cancers with short-course radiotherapy (SRT), 97 with long-course chemoradiotherapy (CRT), and 154 without preoperative treatments, were evaluated for histopathologic features including Crohn's-like reaction (CLR).