Primary Tumour Resection Could Improve the Survival of Unresectable Metastatic Colorectal Cancer Patients Receiving Bevacizumab-Containing Chemotherapy

Background: The effect of primary tumour resection (PTR) among metastatic colorectal cancer (mCRC) patients remains controversial. Combination chemotherapy with bevacizumab could improve the clinical outcomes of these patients, which might change the importance of PTR in the multi-disciplinary treatment pattern. Methods: We performed a non-randomized prospective controlled study of mCRC pts whose performance status (PS) scored ≤2 and who received bevacizumab combination chemotherapy (FOLFOX/XELOX/FOLFIRI) as a first-line therapy. These patients were classified into the PTR group and the IPT (intact primary tumour) group according to whether they underwent PTR before receiving the systemic therapy. The progression free survival (PFS) time and overall survival (OS) time, which were recorded from the start of the primary diagnosis until disease progression and death or last follow-up, were analysed. We also compared severe clinical events (such as emergency surgery, radiation therapy, and stent plantation) between the two groups. Results: One hundred and nighty-one mCRC pts (108 male patients and 93 female patients) were entered in this prospective observational study. The median age was 57.5 years old. The clinical characteristics (age, gender, performance status, primary tumour site, RAS status, and the number of metastatic organs) did not significantly differ between the two groups. The median PFS and OS times of the PTR group were superior than those of the IPT group (10.0 vs 7.8 months, p < 0.01 and 22.5 vs 17.8 months, p < 0.01, respectively). The incidences of adverse events associated with systemic therapy were similar between the two groups. Specifically, sixteen patients (21.9%, 16/73) with IPT developed significant primary tumour-related complications, such as bleeding, obstruction or even perforation. Among these patients, five underwent emergency surgery, three patients received a stent, and eight patients underwent radiation therapy. Conclusions: The mCRC patients who received PTR and bevacizumab combination chemotherapy had better clinical outcomes than patients who did not receive PTR. PTR also decreased the incidence of severe clinical events and improved quality of life.