RESUMO
INTRODUCTION: This research aimed to demonstrate the correlation of circulating endothelial cells (CECs) count and serum cytokine levels with side effects and prognosis in rectal cancer patients receiving adjuvant chemoradiation. METHODS: Eleven patients received proctectomy, chemoradiotherapy and follow-up for 4 years. Fifty-five blood samples were taken before radiation and during the course. The quantities of CECs were estimated by flow cytometry, and serological factors were measured by ELISA. RESULTS: The CEC level in patients without tumor recurrence was significantly lower than in patients with tumor recurrence (p < 0.01). The IL-6 and TGF-ß1 levels exhibited a similar profile (p < 0.01). For morbidity, the mean CEC level in patients with grade 3 diarrhea was significantly greater than patients with grades 1 (p < 0.001) and 2 diarrhea (p < 0.005). CONCLUSIONS: Levels of CECs, serum IL-6, TGF-ß1 and TNF-α during post-operative chemoradiation in rectal cancer patients might be candidate biomarkers for prognosis and morbidity (NCT00325871).