ABSTRACT
INTRODUCTION: Colorectal cancer (CRC) outcomes vary depending on tumour biology, with several features used to predict disease behaviour. Extramural venous invasion (EMVI) is associated with negative outcomes and its presence has been established as an indicator of more aggressive disease in CRC. METHODS: A prospectively maintained database was examined for patients undergoing curative resection for non-metastatic CRC between 2012 and 2018 in a tertiary institution. Clinicopathological factors were compared to assess their impact on recurrence, all-cause mortality and cancer-related death. Kaplan Meier analysis of the association between EMVI and these endpoints was performed, and univariable and multivariable analysis was carried out to establish the relationship of predictive factors in oncological outcomes. RESULTS: Eighty-eight (13.5%) of 654 patients developed recurrence. The mean time to recurrence was 19.8 ± 13.5 months. There were 36 (5.5%) cancer-related deaths at a mean duration of follow-up of 46.3 ± 21.6 months. Two hundred and sixty-six patients had extramural venous invasion (40.7%). EMVI was significantly associated with reduced overall recurrence-free survival, systemic recurrence-free survival, and increased cancer-related death on univariate analysis (p < 0.001 for all, Fig. 1), and multivariable analysis (OR 1.8 and 2.1 respectively, p < 0.05 for both). CONCLUSION: EMVI is associated with a poor prognosis, independent of stage, nodal status and other histopathological features. The presence of EMVI should be strongly considered as an indication for adjuvant therapy.
