Longterm effects of palliative local treatment of incurable metastatic lesions in colorectal cancer patients

We assessed the value of palliative local treatment of incurable metastatic lesions in colorectal cancer patients. Consecutive patients with metastatic colorectal cancer treated between 2003 and 2014 were retrospectively reviewed. Propensity score matching was used to create comparable palliative local treatment and chemotherapy alone groups (n = 272 in each group). The primary endpoint was overall survival, which was calculated using Kaplan-Meier survival analyses. Factors possibly influencing survival were evaluated by univariate and subsequently by multivariate analyses. Palliative local treatment prolonged survival as compared with chemotherapy alone (38.73 vs. 19.8 months, p < 0.01). Univariate and subsequent multivariate analyses showed that primary stage IV at initial diagnosis; high CA199 level and LDH at the time of diagnosis were independent factors for a poor prognosis. Palliative local treatment improved survival better than chemotherapy alone in patients with 0, 1, 2, or 3 of the prognostic factors (p < 0.01). Patients administered treatment for pulmonary metastases survived longer than those treated for metastases elsewhere (56.77 vs. 35.43 months, p = 0.01). Surgical treatment provided marginally longer survival than non-surgical treatment (44.87 vs. 35.43 months, p = 0.05). These findings suggest palliative local treatment has survival benefit for selected patients with incurable metastatic colorectal cancer.