Feasibility of endoscopic techniques in assessing the radicality of chemoradiotherapy in patients with rectal cancer

Introduction. The standard of treatment of rectal cancer is a combined or complex technique in the form of neoadjuvant chemoradiotherapy (CRT) followed by surgery or observation, with proven radicalization of CRT. Currently, the most adequate methods of evaluating the results of CRT are endoscopic diagnostics. The most reliable visual criteria for endoscopic examination of absence or presence of residual tumor are: complete response (flat white scar, telangiectasia), partially complete response (uneven mucosa, small nodules on mucosa, superficial ulceration, slight persistent erythema of scar) and incomplete response (visible tumor).

Aim. The study is to assess sensitivity and specificity of endoscopic method in assessment of radicality of neoadjuvant CRT in patients with rectal cancer.

Materials and methods. A retrospective study of 75 patients with verified rectal cancer after CRT was carried out. Inclusion criteria: histologically verified rectal cancer (adenocarcinoma); endoscopic picture of clinical response of rectal cancer to CRT; absence of established distant metastases at the moment of examination. Exclusion criteria: morphological types of tumors other than adenocarcinoma of the colorectal type; patients with primary-multiple diseases.

Results. A retrospective study was conducted in 75 patients with a verified diagnosis of rectal cancer who underwent CRT at the first stage of treatment. All patients underwent endoscopic examination with evaluation of the degree of tumor regression, taking material for cytological and histological examination. In 57 (76,4 %) out of 75 patients on the basis of visual endoscopic picture the absence of residual tumor was stated, in 18 patients visual endoscopic signs were considered as presence of residual tumor. The results of morphological study in the first group of patients confirmed the absence of tumor in 51 cases (92.7 %). In the second group, in the presence of visual signs of residual tumor, morphological confirmation was obtained in 14 out of 18 patients (77.8 %). Morphological verification of residual tumor was obtained in 26.6 % of patients in the total group.

Conclusion. Endoscopic and histologic data can be decisive in the evaluation of the degree of radicality of neoadjuvant CRT.