Retrospective evaluation of the effectiveness and results of neoadjuvant chemoradiotherapy in rectum adenoccancer patients

Colorectal cancer is the third most common cancer worldwide and the second most common cancer-related mortality. Mortality due to rectal cancer is around 4-10/100.000 per year. Especially locally advanced rectal cancers have a special place in medical oncology follow-up protocols due to their local aggressive nature, progression pattern and tendency to respond to chemoradiotherapy. Studies have shown that local recurrence rates are reduced by preoperative chemoradiotherapy (CRT) and subsequent surgical resection. In light of this information, preoperative neoadjuvant therapy has become a standard treatment modality in patients with locally advanced rectal cancer to reduce tumor stage and reduce local recurrence. The aim of this retrospective study was to investigate the demographic, clinical, laboratory and radiological characteristics of patients with rectal cancer admitted to our center and to compare the overall survival and disease-free survival with neoadjuvant chemoradiotherapy to current literature. In our study, patients were evaluated in terms of age, sex, clinical staging, pathologic staging, carcinoemrionic antigen levels, treatment protocols and durations, survival time and time to progression Of the 104 patients, 25 had complete pathologic response, 26 had stage IA, 29 had stage IIA, 6 had stage IIIA, and 17 had stage IIIB. There was a significant difference in disease-free survival between full-response and stage IA patients and other groups (p: 0.034). The mean follow-up period was 48.5 months. Of the 104 patients, 24 patients had recurrence and 18 patients died. 3-year overall survival was 91.3%, 5-year overall survival was 81%. Disease-free survival was 77.8% at 3-year follow-up and 74.1% at 5-year follow-up. Factors affecting survival time were evaluated. No correlation was found between clinical staging, cT, cN groups and survival and disease-free survival, whereas pathological staging was effective on disease-free survival. In conclusion, it was confirmed that neoadjuvant chemoradiotherapy is beneficial for disease-free survival in rectal cancer patients without distant metastasis. Keywords: rectal cancer, neoadjuvant treatment, locally advanced cancer.