Comparison of Treatment Outcomes in Patients with Rectal Cancer

Objective: The aim of the present study is to evaluate survival results and acute chemoradiotherapy toxicity in patients with rectal cancer who underwent preoperative chemoradiotherapy (CRT), postoperative CRT, and non-operative CRT. Methods: The records of 139 patients with rectal cancer were analyzed retrospectively. Out of these, the data 9 (6%) patients who died during or immediately after treatment and 2 (1%) patients who gave up the treatment were not used in the survival analysis. Results: Postoperative CRT was applied to 57 (44%) patients, preoperative CRT to 47 (37%) patients, and non-operative CRT to 24 (19%) patients. Non-operative CRT group was the oldest patient group (median age: 70). There was a difference between the treatment groups regarding tumor localization (p<0.001), pathological stage (p<0.001), lymphovascular (LVI, p<0.004), and perineural invasion (PNI, p=0.017). A difference was determined between the groups regarding median follow-up and the postoperative CRT group had the longest median follow-up (p<0.001). A difference was also determined between the groups regarding local recurrence and distant metastasis (p=0.467 and p=0.901, respectively). The three-year overall survival and disease-free survival rates were 78% and 78% for the postoperative CRT group, 76% and 73% for the preoperative CRT group, and 48% and 41% for the non-operative CRT group (p<0.001 and p<0.001, respectively). However, the difference between preoperative and postoperative CRT regarding overall survival and disease-free survival was not determined since the non-operative CRT group was included in survival analysis (p=0.184 and p=0.073, respectively). No difference found among the three groups regarding the adverse effects of chemoradiotherapy (p>0.050). Conclusion: While no difference was determined between preoperative and postoperative CRT applications regarding local recurrence and distant metastasis, overall survival and disease-free survival, and adverse effects of treatment, LVI, and PNI determined in earlier pathological stage and lower frequency for the preoperative application. However, overall survival results of patients receiving non-operative CRT were worse as compared to patients receiving operative CRT.