This study aimed to determine the impact of venous invasion (VI) characteristics on oncological outcomes in colorectal cancer (CRC). Resection specimens from 368 patients with TNM stages I-III CRC were assessed for VI including its presence/absence, location intramural (IMVI) or extramural (EMVI), number and size of the largest VI focus. VI and EMVI were identified in 55% and 32% of cases, respectively. EMVI, but not IMVI, was significantly associated with decreased 5-year recurrence-free survival (RFS) and disease-specific survival (DSS) (hazard ratio HR 4.2, 95% confidence interval CI 2.6-6.9 and 3.7 95% CI 1.9-6.9, p 5 EMVI foci (n = 31) had a particularly poor prognosis with 5-year RFS and DSS of 29% and 56%, respectively. EMVI dimensions were not associated with oncological outcomes. Extramural location and multifocality are features of VI strongly associated with adverse oncological outcomes. If externally validated, incorporation of EMVI multifocality into future reporting protocols merits consideration.
Sarı et al. (Wed,) studied this question.