Prognostic factors predicting survival in incurable stage IV colorectal cancer patients who underwent palliative primary tumor resection. Retrospective cohort study

The aim of this study is to estimate prognostic factors predicting survival in patients with incurable stage IV colorectal cancer (CRC), who underwent palliative primary tumor resection (PTR) with chemotherapy. We retrospectively performed an analysis using clinicopathological parameters of 103 patients with incurable stage IV CRC, who underwent palliative PTR with chemotherapy between 2006 and 2010. Prognostic factors associated with overall survival (OS) were evaluated by univariate and multivariate analyses. The median follow-up time was 17.5 months (range 2.4–60.5) for the total cohort (n = 103). There were five independent factors related to OS in univariate analysis (body mass index, tumor differentiation, pT, pN stage and local clearance of the primary tumor). A multivariate analysis revealed that pT, pN and local clearance of the primary tumor were prognostic factors related to OS. Median survival months (95% CI) were pT1, 2, 3: 21.5 (16.23–26.77) months vs. pT4: 13.73 (9.94–17.53) months, pN-: 29.7 (22.55–35.99) months vs. pN+: 17.1 (15.0–19.41) months and R0: 18.57 (16.65–20.48) months vs. R1, 2: 12.43 (9.95–14.91) months. Locally advanced primary tumor (high pT stage, positive regional lymph node, and local residual primary tumor) was associated with poorer OS in incurable stage IV CRC patients, who underwent palliative PTR with chemotherapy. The PTR appears to result in better OS in patients with a primary tumor that is not locally advanced.