Early-onset non-metastatic colon cancers do not portend worse prognosis - implications for adjuvant chemotherapy.

Abstract

Early-onset colon cancers are increasing and the independent influence of age on prognosis and therapeutic efficacy of adjuvant therapy is unclear. The primary aim of the present study was to determine if young age was an independent prognostic factor for survival. Secondarily, age would be used in the context of known factors that predict benefit with adjuvant chemotherapy in stages II and III. Retrospective, single centre study of operated, non-metastatic colon cancer (> 15cm from anal verge) without pre-operative therapy. Early onset cancers were defined as age ≤ 45years. Primary endpoint was disease-free survival (DFS). Six-hundred thirty-three patients were included with 206 (32.5%) early-onset cancers. With a median follow-up of 48months, 5-year DFS was 79.5% and 76.2% for early and late-onset cancers, respectively (p - 0.585). In multivariate analysis, only tumour sidedness, family history, T4 stage, node positivity and microsatellite instability status influenced DFS and not the age of onset (HR - 0.969; 95% - 0.63-1.49). These results were consistent with different models and with stage-wise distribution. Early-onset colon cancers treated with curative intent had survivals similar to older cohorts. Age was not an independent prognostic factor for recurrences. Age did not influence disease-free survival when stage-wise predictive variables for therapeutic benefit with adjuvant chemotherapy were considered.