[Comparison of preoperative chemotherapy with concurrent chemoradiotherapy combined with TME for 305 patients with locally advanced rectal cancer].

Objective: To retrospectively analyze the long-term efficacy and prognostic factors of preoperative chemotherapy (PCT) or chemoradiotherapy (PCRT) combined with total mesorectal excision in locally advanced rectal cancer. Methods: Clinical pathology data of 305 patients with localized advanced rectal cancer admitted to the Cancer Hospital, Chinese Academy of Medical Sciences from 2006 to 2018 were collected, of whom 246 patients received PCRT (PCRT group), 59 patients received PCT (PCT group). Kaplan-Meier and Log rank test were used for the survival analysis, Cox regression model was used for multivariate analysis, and the prognosis of two groups of patients were compared by the propensity score matching (PSM). Results: In the whole group of 305 patients, 20 cases of tumors located in the upper part of the rectum and at the junction of rectum and colon, 96 cases in the middle of the rectum and 189 cases in the lower part of the rectum. PCRT group included 38 cases of cT2-3 phase, 11 cases of cT4a stage, 10 cases of cT4b stage, while the cases in PCT group were 184, 0 and 62 cases, respectively, the difference is statistically significant (P<0.05). The R0 excision rates of PCRT group and PCT group were 100% (246/246) and 96.6% (57/59), respectively, and the total pathological remission rates were 13.4% and 3.3%, respectively (P<0.05). After PSM, the 3-year survival rates of PCRT group and the PCT group were 86.6% and 89.9% (P>0.05), respectively, and the progression-free survival rates were 74.6% and 77.2% (P>0.05), local recurring free survival rates were 100% and 92.3% (P>0.05), distant metastasis free survival rate were 75.6% and 77.3% (P>0.05). Pre-treatment N-positive, N-degeneration and MRF-positive were all associated with total survival (P<0.05). Conclusion: In the PCRT group, with a higher proportion of patients with stage T4b and lower rectal cancer, the long-term efficacy of PCRT was similar to that of PCT, and higher R0 excision rate and pathological complete response rate could be obtained.