Роль адъювантной химиотерапии у больных раком прямой кишки после предоперационной химиолучевой терапии: результаты ретроспективного исследования

Abstract

Objective: to evaluate the prognostic value of clinical and pathomorphological stages in patients with rectal cancer after preoperative chemoradiotherapy and to assess the effectiveness of adjuvant chemotherapy in these patients. Materials and methods. We conducted a retrospective analysis of the data from a prospectively maintained database for patients with rectal cancer. The study cohort included patients with stages I–III rectal cancer that underwent preoperative chemoradiotherapy followed by surgical treatment performed in the Department of Proctology and Clinical Pharmacology and Chemotherapy between 2004 and 2013. The relapse-free and overall survival rates were assessed to estimate treatment efficacy. Results. A total of 457 patients were eligible for the study; of them 98 patients (21.4 %) received adjuvant chemotherapy. The following independent factors were found to negatively affect relapse-free survival: perineural invasion (р <0.01; hazard ratio (HR) 3.1; 95 % confidence interval (CI) 1.43–6.89), preoperative neutrophil-lymphocyte ratio ³ 3 (р = 0.01; HR 1.8; 95 % CI 1.37–2.42) and pathomorphological stage (р <0.01; HR 1.82; 95 % CI 1.37–2.42) (but not clinical stage). The pathomorphological stage (р <0.01; HR 1.9; 95 % CI 1.30–2.65), invasion into lymphatics (р <0.01; HR 2.4; 95 % CI 1.27–4.59) and white blood cell count ³ 11 000/µL (р <0.01; HR 13.1; 95 % CI 1.33–7.33) were independently associated with poorer overall survival. We observed a trend towards a decline in the relative risk of death in patients with stage yp3N0M0 cancer in response to adjuvant chemotherapy (р = 0.1; HR 0.4; 95 % CI 0.01–37.6). There was also a trend towards better relapse-free and overall survival in adjuvant chemotherapy-treated patients with stage ypT0–4N1–2 (р = 0.1; HR 0.65; 95 % CI 0.4–1.1 and р = 0.3; HR 0.3; 95 % CI 0.4–1.4 respectively) and stage yр T0–4N2M0 (р <0.01; HR 0.3; 95 % CI 0.14–0.70 and р = 0.03; HR 0.5; 95 % CI 0.2–1.0) cancer. Conclusion. In patients with rectal cancer, the pathomorphological stage appears to be a more reliable prognostic parameter compared to the clinical stage; this should be considered when prescribing adjuvant chemotherapy to patients that underwent preoperative chemoradiotherapy.