Microsatellite instability in colorectal cancer is associated with local lymphocyte infiltration and low frequency of distant metastases

摘要: Colorectal carcinomas (CRCs) with high microsatellite instability (MSI-H) share clinicopathological features distinctly different from their stable (MSS) counterparts. Unlike MSS cancers, MSI-H CRCs occur predominantly in the right-sided colon and are often characterised by a strong lymphocyte infiltration. A poor differentiation pattern is found most CRCs, even though patients seem to have significantly longer survival after surgical resection. To clarify which factors contribute obvious paradoxon of more favourable prognosis MSI tumours, several clinical histopathological as well status were evaluated 120 colorectal cancer cases fulfilling criteria (Bethesda) indicative for familial cancer. Microsatellite instablity infiltration related tumour stage patients' follow-up. Statistical analysis confirmed well-known relations, such enhanced accompanied Crohn's like reaction (CLR) cancers (CLR+ 27 out 47 vs 14 71 P<0.001). However, stratification depth local invasion penetration primary tumour, T3 tumours displaying had lower rate distant metastases (M1 four 35 20 41 similar tendency was observed CLR-positive six 29 CLR+ 17 45 CLR− P=0.13). In logistic regression model, phenotype presence CLR independent predictors low UICC (P=0.006 0.04, respectively). These data, together recent definition highly immunogenic neo-antigens expressed cells, suggest that elicit protective host response may prevent metastasis formation.