Pelvic local recurrence as first relapse predicts prognosis for clinical stage II/III lower rectal cancer: A clinicopathological investigation

The present study investigated the association between the mode of tumor recurrence and prognosis in 123 patients with clinical stage II/III rectal cancer. In the past 10 years, patients received systemic chemotherapy following radical (R0, with no macroscopic residual tumor lesions) resection using total or tumor-specific mesorectal excision. Patients with rectosigmoid cancer and T4 + chemoradiation therapy were excluded from the present study. The 5-year relapse-free survival rate (5Y-RFS), 5-year overall survival rate (5Y-OS), and associations between early post-operative complications, recurrence mode and prognosis, as well as the 5Y-OS of patients with relapsed cancer, were calculated. The overall 5Y-RFS and 5Y-OS were 71.4 and 83.5%, respectively, and the overall recurrence rate was 22.8% (28/123 patients). Among relapses, remote metastases were observed in 17/123 patients (13.8%): The lung in 8 patients (6.5%), the liver in 5 patients (4.1%) and elsewhere in 4 patients (3.3%). A total of 11 patients (8.9%) had pelvic local recurrence as the first relapse, which was located anterior to the sacrum in 7 patients (5.7%), at the anastomosis site in 2 patients (1.6%), and in the inner pelvis in 2 patients (1.6%). Among relapsed patients, the 5Y-OS was 69.3% in those with distant metastases and 27.3% in those with local relapse (P=0.02; no significant differences in patient demographics). The results indicated that advanced rectal cancer and control of pelvic local recurrence are manageable by R0 resection and postoperative chemotherapy. However, for patients whose initial relapse was pelvic local recurrence, the relapsed tumor initiated a new metastatic cascade to organs, such as the lung and liver, and affected prognosis.