The impact of palliative primary tumor resection on overall survival in minimally symptomatic (asymptomatic) colorectal cancer and synchronous unresectable metastases vs chemotherapy only: a comparative study of outcomes

Abstract

Aim: to evaluate the impact of primary tumor resection (PTR) on treatment outcomes in patients with asymptomatic or minimally symptomatic colorectal cancer (CRC) and synchronous unresectable metastases.Patients and Methods: treatment outcomes of patients with minimally symptomatic CRC and synchronous unresectable metastases were retrospectively assessed (2016–2022). Patients with PTR followed by chemotherapy were compared to patients receiving chemotherapy only. Survival was determined by the Kaplan-Meier method and differences were evaluated using the log-rank test and Cox proportional-hazards regression model. To reduce potential selection bias between two groups a propensity score matching (PSM) was performed.Results: no significant differences in 30-day mortality rate (р = 1,00) and the rate of surgical intervention due to complications of first treatment (р = 1,00) between the two groups. Before matching the median survivals were 27,8 and 24 months in the PTR and chemotherapy groups, respectively (р = 0,2). After PSM the overall survival rate at 3 years was 42,1% for the PTR group and 34% for the chemotherapy group (р = 0,47). The median survivals were 27,9 and 24,4 months, respectively. Three-year overall survival rate for patients with stage IVB was significantly higher in the PTR group than in the chemotherapy group (37,8% versus 4,8%; р = 0,02). The median survivals were 36,1 and 17,2 months, respectively. In multivariate analysis radical resection (R0) if unresectable metastases converted into resectable after initial treatment was the only significant prognostic factor for survival (p < 0,001).Conclusions: PTR in patients with asymptomatic or minimally symptomatic CRC and synchronous unresectable metastases is associated with acceptable postoperative morbidity and mortality rates and may improve overall survival for patients with stage IVB comparing to chemotherapy as a treatment of first line. However, randomized controlled trials are needed.