The aim of the study: to examine the indicators of relapse-free survival and evaluate prognostic factors that had the greatest impact on relapse- free survival in patients with rectal cancer complicated by obstructive obstruction and undergoing emergency surgery.

Materials and methods. The analysis of the immediate and long-term results of treatment – relapse-free survival of patients undergoing emergency surgery for rectal cancer complicated by obstructive obstruction in general surgical and specialized hospitals in Smolensk from 2001 to 2017 is presented. Relapse-free survival was analyzed by the Kaplan–Meier method. To determine the influence of potential risk factors on the rate of occurrence of the studied event, Cox regression was used.

Results. Postoperative complications of the III–IV degree according to Clavien–Dindo were more common in patients undergoing emergency surgery for complicated rectal cancer in general surgical hospitals (p = 0.0056). In specialized hospitals, anastomosis leakage in 5.3 % (1 of 19 cases), in general surgical hospitals – 16.3 % (9 of 55 cases). Five-year relapse-free survival in general surgical hospitals at the IIB stage was 18.3 %, median survival – 32 months; in specialized hospitals at stage IIB 5‑year relapse-free was 45.8 %, median survival – 52 months (p = 0.028 and 0.011, respectively). A multivariate analysis confirmed the influence of the following factors on the performance of a 5‑year relapse-free survival: hospital specialization (risk ratio (RR) 1.35; 95 % confidence interval (CI) 1.18–1.55; p <0.001), type of surgery – one-stage operations (RR 1.13; 95 % CI 1.05–1.22; p = 0.001), the presence of metastases in the lymph nodes (RR 0.77; 95 % CI 0.71–0.84; p <0.0001), the number of examined lymph nodes (RR 0.79; 95 % CI 0.72–0.87; p <0.001).

Conclusions. It is advisable to carry out two-stage surgical treatment with the formation of a colostomy at the first stage; the main stage of radical intervention should be performed in a specialized hospital.

Objective: to determine the predicting factors for the effectiveness of neoadjuvant treatment in colorectal cancer based on the analysis of overall and relapse-free survival, as well as the possibility of multiparametric magnetic resonance imaging (MRI) in stratifying patients into groups with favorable and unfavorable clinical course.

Materials and methods. 112 patients who received preoperative chemoradiotherapy (n = 85) and chemoradiotherapy supplemented with neoadjuvant polychemotherapy (n = 27) followed by surgery were enrolled in retrospective study. To determine the most significant predicting factors and criteria for evaluating the effectiveness of treatment that affect overall and relapse-free survival, Kaplan–Meier estimator and Cox regression were used.

Results. The relapse-free survival was significantly affected by the presence or absence of extramural venous invasion according to MRI (mrEMVI) (p = 0.0001), circumferential resection margin status according to pathomorphological data (pCRM) (p = 0.031), change in volume of tumor (mrVolumetric analysis) (p = 0.015), tumor regression grade according to MRI (mrTRG) (p = 0.017) and pathomorphological data (pTRG) (p = 0.038). Independent predictors of overall survival were: extramural venous invasion according to MRI (mrEMVI) (p = 0.0001), posttreatment N staging (p = 0.047) and tumor regression grade according to MRI (mrTRG) (p = 0.059). Based on the most significant MR criteria, a mathematical model was developed to predict the risk of relapse after neoadjuvant treatment.

Conclusions. MRI allows stratifying patients into groups with a favorable and unfavorable prognosis at the preoperative stage and optimizing the management of patients after surgery taking into account pathomorphological data.

Objective: to analyze the outcomes of sphincter-sparing surgeries in patients with advanced distal rectal cancer depending on the therapy they receive.

Materials and methods. This study included 289 patients with advanced (stage T3N0–2M0) distal rectal cancer who have undergone sphincter-sparing surgeries. Patients were divided into three groups according to their treatment scheme. In group 1, we used combination treatment that included a short course of neoadjuvant radiotherapy supplemented by 3 multidirectional radiomodifiers (local microwave hyperthermia, rectal administration of a biopolymer composition containing metronidazole, and chemotherapy with capecitabine). Patients in group 2 received combination treatment that included neoadjuvant radiotherapy alone. Treatment outcomes in patients receiving combination therapy was compared to those of patients with similar characteristics and location of rectal tumors who have undergone surgery alone in N. N. Blokhin National Medical Research Center of Oncology (group 3).

Results. We observed a significant decrease in the incidence of locoregional cancer metastasis in patients from group 1 compared to those from groups 2 and 3 (0.8 % vs 7.9 % and 18.2 % respectively). Moreover, patients in group 1 demonstrated better relapse-free survival than participants in groups 2 and 3 (79.6 % vs 52.6 % and 51 % respectively). The new scheme of combination therapy developed by our team (used in group 1) did not increase the incidence of postoperative complications. The best local disease control in group 1 was achieved in patients with middle rectal cancer who have undergone sphincter-sparing surgeries: none of 81 patients developed relapses, whereas the relapse-free survival rate reached 83 % compared to 56.9 % in group 1 and 41.7 % in group 3.

Conclusions. The new treatment scheme that includes neoadjuvant radiotherapy supplemented by 3 multidirectional radiomodifiers can be used as one of the options increasing efficacy of radiotherapy and, therefore, efficacy of combination treatment in patients with advanced rectal cancer who undergo sphincter-sparing surgeries.

Objective: to asses safety of installation intracorporeal anastomosis (ICA) in routine practice at learning curve period.

Materials and methods. The results of treatment of 102 patients during 2019 were retrospectively analyzed, of which 64 were operated by an expert and 38 passing the ICA learning curve.

Results. The operation time was shorter for the expert (145 minutes versus 210 minutes, p <0.05), there was no statistical difference in pathomorphological measurements, the number of lymph nodes removed was oncologically acceptable and did not differ significantly in the two groups. The total number of complications was 25.2 % for all patients, and Clavien–Dindo class IIIB complication rate was also the same (3.2 % vs 2.6 %, p >0.05).

Conclusions. The introduction of ICA in right colectomy into routine practice at the stage of passing the learning curve is safe and applicable.

Objective: to evaluate short-term and long-term outcomes of lymph node dissection in patients with stage III–IV ovarian cancer.

Materials and methods. This retrospective study included patients with stage III–IV ovarian cancer who have undergone either complete or optimal cytoreduction. Patients in the experimental group additionally had lymph node dissection, whereas patients in the control group had surgery without lymph node dissection. We evaluated 3‑year relapse-free survival (primary outcome measure), 3‑year overall survival, incidence of intraoperative and postoperative complications, and frequency of lymph node lesions.

Results. The study included 272 patients: 43 women in the experimental group and 229 women in the control group. Intraoperative complications were significantly more common in patients who had lymph node dissection compared to those who had cytoreductive surgery alone (37.2 % vs 16.6 % respectively; р = 0.0001). The incidence of postoperative complications did not vary significantly between the groups (27.9 % in the experimental group vs 16.2 % in the control group; р = 0.128). Thirty-three patients (76.7 %) were found to have metastasis in the lymph nodes excised. The three-year overall survival rate was 82.6 % among patients who had lymph node dissection and 75.7 % among patients who had no lymph node dissection (р = 0.306). The three-year relapse-free survival rate was 26.2 % in the experimental group and 38.4 % in the control group (р = 0.858).

Conclusions. Systemic lymph node dissection does not improve long-term outcomes and increases the incidence of intraoperative complications in patients with stage III–IV ovarian cancer undergoing complete or optimal cytoreduction.

Objective: to evaluate feasibility and short-term results of the liver-first approach in our center.

Materials and methods. Retrospective study of prospectively gathered group of patients who were treated in N. N. Blokhin National Medical Research Center of Oncology between 2017 and 2019. Patients with asymptomatic primary tumor located in rectum and rectosigmoid junction with synchronous resectable / borderline resectable metastasis in liver. 22 patients were planned to undergo the liver-first approach. Post-operative morbidity and mortality (Clavien–Dindo) as well as tumor regression grading (Dworak) were evaluated.

Results. Of the 17 patients planned to undergo the liver-first strategy, the approach was completed in 15 (88,2 %) patients. The main reason for treatment failure was disease progression. Post-operative morbidity and mortality were 13,3 % and 0 %, respectively.

Conclusions. Liver-first approach is justified in two cases: during waiting period after last day of chemoradiotherapy in patients with locally advanced (invasion depth T4a, positive circumferential resection margin, N+ status) mid-to-low rectal cancer and in patients with multiple borderline resectable bilobar liver damage.

Objective: epidemiological evaluation of global trends in colorectal cancer and assessment of colon cancer incidence in the Republic of Uzbekistan in 2012–2017.

Materials and methods. We used GLOBOCAN data to analyze the situation with colorectal cancer worldwide. We also assessed the incidence of colon cancer, trends, and mean age of patients (by years) registered in the Republic of Uzbekistan. This article emphasizes the need for epidemiological studies of colorectal cancer in Uzbekistan.

Results. World trends in colorectal cancer incidence and mortality indicate that these parameters vary across different regions and depend on the economic situation. There are also some sex differences: men are more likely to develop colorectal cancer than women (male to female ratio 1.25:1.0). The number of patient died of colorectal cancer is growing; the male to female ratio is 1.22:1.0.

Conclusions. Our assessment of epidemiological situation of colon cancer in the Republic of Uzbekistan demonstrated that its incidence tends to increase, which necessitates further research evaluating regional differences and risk factors for colorectal cancer.