Introduction. Given the limited possibilities of objective registration of all features of inpatient treatment in oncology, the study of the opinion of patients on this issue seems to be an urgent area of research. The aim of the study: to study the opinion of patients who have completed antitumor treatment of rectal cancer (RC) about the medical care received in an oncological hospital. Materials and methods. During the study, a specially developed questionnaire was used to conduct a sociological survey of 424 patients with RPC who underwent inpatient treatment at the Yaroslavl Regional Clinical Oncological Hospital. The average age of patients was 57.8 ± 11.8 years. All patients underwent RC surgery. In 31.0% of observations, it was supplemented with radiation treatment, in 62.1% - with chemotherapy. Primary materials were processed using variational statistics in Statistica v.13.0 (Stat Soft Inc, USA). Results and discussion. According to the data obtained, 64.3% of patients underwent colostomy during surgery, 28.6% in the postoperative period experienced problems associated with wound healing and colostomy. Among respondents, 37.9% reported a violation of their social activity after surgery. Recommendations for the care of wound, stoma, motor activity from the attending physician received only 59.1% of patients, 22.2% were forced to independently search for information on the Internet. Among the methods of antitumor treatment, according to patients, chemotherapy has the highest frequency of complications - 73.9% of patients noted adverse events after it. The study revealed clinical and organizational and ethical-deontological problems associated with the development of complications of antitumor treatment, the elimination of which will help reduce the frequency of complications, improve the continuity in the work of inpatient and outpatient departments, increase the efficiency of interaction between the doctor and the patient during treatment and, as a result, increase patient satisfaction. Conclusions. The identified clinical and organizational and ethical and deontological problems associated with the development of complications of antitumor treatment of RC should be taken into account when developing effective management solutions for their prevention.