Analysis on risk factors of the degree of radical resection and prognosis of patients with locally recurrent rectal cancer

Abstract

Objective: To evaluate the factors affecting the degree of radical resection and the prognosis of patients with locally recurrent rectal cancer (LRRC). Methods: A retrospective case-control study was performed. Clinical data of 111 patients with LRRC undergoing operation at the General Surgery Department of Peking University First Hospital from January 2009 to August 2019 were analyzed retrospectively. The "Peking University First Hospital F typing" was performed according to the preoperative images of the pelvic involvement. The pelvis was assigned into four directions: the front wall, lateral sides of the pelvic wall and the sacrum. According to the degree of pelvic wall involvement, F typing included F0 type (no involvement of the pelvic wall, the cancer only involved the adjacent organs or invaded conteriorly the urinary tract, genital organs or small intestine), F1 type (cancer involved the pelvic wall in one direction, such as the sacrum, or one side of the pelvic wall), F2 type (cancer involved the pelvic wall in two directions) and F3 type (cancer involved the pelvic wall in three directions). Case inclusion criteria: (1) LRRC was confirmed by imaging and pathological examination of samples (puncture or endoscopic biopsy); (2) complete clinical and follow-up data; (3) informed consent of patient. Those with dysfunction of heart, lung, etc., intolerance of operation, F3 type indicated by image, and distant metastasis were excluded. The degree of radical resection was evaluated according to the postoperative pathological results. Patients were followed up every 12 months and related examinations were arranged. The univariate analysis of radical resection was performed by χ(2) test, and the multivariate analysis was performed by logistic methods. The survival rate was calculated by Kaplan-Meier method and the survival curve was drawn. The survival rate was compared by log-rank test. Cox proportional hazards model was used to analyze the factors affecting the prognosis of patients with LRRC. Results: A total of 111 patients were included in this study. Of 111 patients, 59 were male and 52 were female; recurrent age of 36 cases was ≥ 65 years old; CEA level of 48 cases was ≥15 μg/L. According to the "Peking University First Hospital F typing", 70 cases were F0 type, 38 F1 type and 3 F2 type. Surgical procedures were abdominoperineal resection (n=28), posterior pelvic exenteration (n=32), and total pelvic exenteration (n=51, including 1 case of TPE combined with sacrectomy). According to the postoperative pathological results, R0, R1 and R2 resections were 83, 20 and 8 cases, respectively. Univariate analysis showed that the degree of radical resection was associated with the secondary surgical procedure, F typing and lymph node metastasis (all P<0.05). Multivariate analysis showed that F typing (F1-F2) was an independent risk factor for non- R0 resection (OR=37.256, 95%CI:8.572 to 161.912, P<0.001). The morbidity of operative complications was 22.5% (25/111); the perioperative mortality was 1.8% (2/111); the local recurrence rate after the second operation was 37.8% (42/111). The 3- and 5-year overall survival rates were 41.2% and 21.9% respectively. The 3-year survival rates of patients with and without postoperative chemotherapy were 52.7% and 32.4% respectively (P=0.005). The 3-year survival rates of patients with lower (<15 μg/L) and higher CEA level (≥15 μg/L) were 52.9% and 24.3% respectively (P<0.001). The 3-year survival rates of patients with R0, R1 and R2 resection were 49.8%, 21.3% and 8.5% respectively (P=0.002). The 3-year survival rates of patients with F0, F1 and F2 type were 52.7%, 22.0% and 0 respectively (P<0.001). Cox analysis confirmed that the degree of radical resection (HR=2.088, 95%CI:1.095 to 3.979, P=0.025), the CEA level before the secondary operation (HR=1.857, 95%CI:1.157 to 2.980, P=0.010) and postoperative chemotherapy (HR=1.826, 95%CI:1.137 to 2.934, P=0.013) were independent factors affecting the prognosis. Conclusions: The indication of LRRC surgical treatments must be strictly limited. Evaluation of the fixation site to the pelvic wall is helpful for improving the rate of R0 resection. Lower preoperative CEA level, radical resection and postoperative chemotherapy are protective factors of prolonged overall survival time of patients with LRRC.