Evaluation of Hematological/Pathological Prognostic Factors and Oncological Outcomes of Patients with Locally Advanced Rectal Cancer Treated with Neoadjuvant Radiotherapy
1Department of Radiation Oncology, Tokat Gaziosmanpaşa University Faculty of Medicine, Tokat-Turkey DOI : 10.5505/tjo.2019.2148 OBJECTIVE
In this study, we aimed to present our results of overall survival (OS), progression-free survival (PFS) and local control (LC) in approximately five years of follow-up of the patients with locally advanced rectal cancer who underwent neoadjuvant radiotherapy (RT) and to investigate both the pathological and hematological parameters that affect the survival.

A total of 76 patients with a pathologic diagnosis of rectum adenocarcinoma and clinical stage I- IVA who underwent neoadjuvant RT between August 2014 and March 2019 were evaluated retrospectively in this study. Eighty-five percent of the patients received 45/50 Gy doses of RT concomitantly with oral capecitabine. Fifty-eight patients (78.4%) underwent surgery. The median time between the completion of RT and surgery was 65 days.

The median follow-up was 25 months. The 2-year OS, PFS and LC rates were 85%, 83.7% and 85.2%, respectively. Positive radial surgical margin was a significant prognostic factor for OS and PFS, but not for LC. The factor affecting OS, PFS and LC was adverse tumor histology (undifferentiated). The prolongation of the time from completion of RT to surgery caused OS and LC to deteriorate. Local control significantly decreased in patients without concomitant chemotherapy. Among all the hematological parameters (e.g. albumin, WBC, platelet, neutrophil, CA 19-9), only pre RT Hb levels significantly correlated with OS but not with PFS. CEA"s response to neoadjuvant treatment (NAT) significantly increased OS and PFS.

Adverse tumor histology, the prolonged time from completion of RT to surgery, CEA"s response to NAT and pre RT Hb levels were essential factors that affect survival. Keywords : Hematologic factors; neoadjuvant radiotherapy; outcome; prognostic factors; rectal cancer