Aim. Our systematic review and meta-analysis aimed to compare studies with primary mesorectumectomy (pME) and “salvage mesorectumectomy” (sME) after transanal endomicrosurgery for patients with early rectal cancer.

Materials and methods. We selected publications from 1 January 1999 to 1 April 2023. A total of 7 studies were included after screening. Following indicators were compared: quality of mesorectum, frequency of abdominoperineal resection, frequency of local recurrence and distant metastases, mortality, morbidity, time of surgery, post-operative stay, frequency of involvement of circular resection margin. Statistical data was processed using ReviewManager 5.3.

Results. Statistically significant differences were observed in probability of intraoperative damaging of mesorectal fascia (Odds Ratio (OR) 0.42; 95 % Confidence Interval (CI) 0.24–0.72, р = 0.002). There were also a trend towards decreasing of number of sphincter-preserving operations after transanal endomicrosurgery (TEM) (OR 1.84; 95 % CI 0.96–3.52, р = 0,06). Other indicators didn’t reach statistical significance when compared.

Conclusion. sTME is a safe procedure and comparable with pME. However, previous TEM is considered a risk factor for damaging of mesorectum, intraoperative perforation and abdominoperineal resection.

Aim. The ensuring that changes to clinical guidelines can be discussed more widely before they are formally introduced into clinical practice.

Materials and methods. A brief review of the literature and rationale for each proposed major change in the treatment section is presented. The refusal to carry out preoperative radiation therapy for cancer of the upper ampullary rectum, the narrowing of indications for preoperative radiation therapy for cancer of the mid-ampullary rectum, as well as the expansion of indications for total non-adjuvant chemotherapy for rectal cancer with damage to the circular resection margin are discussed. Changes to the drug treatment section are discussed.

Results. This article presents planned changes to clinical guidelines for the treatment of non-metastatic colorectal cancer in 2024. The most significant alterations concerned neoadjuvant treatment of rectal cancer and adjuvant treatment of colon cancer. A new algorithm was proposed for choosing rectal cancer neoadjuvant therapy, considering individual treatment decisions.

Conclusion. A consensus was achieved concerning the necessity to expand indications for neoadjuvant rectal cancer chemotherapy, but only in patients with good functional status. The most benefit can be achieved in patients, for whom complete clinical response is the aim of the treatment and in patients with positive circumferential resection margin.

Introduction. The incidence of colorectal cancer for 2020 was 1931590 cases, which is 10 % of all new cases of incidence, and mortality from colorectal cancer ranks 2^nd among cancer deaths, it is 935 173 cases (9.4 %) according to Globocan 2020. According to statistics of the Kazakh Research Institute of Oncology and Radiology for 2019–2020 сolorectal cancer ranks 3^rd in the structure of oncopathology, both in terms of morbidity and mortality. The occurrence of colorectal cancer is associated with an interaction that occurs at several levels between hereditary, environmental and individual factors. Understanding the molecular basis is important because it can identify factors that initiate development, maintain progression, and determine response or resistance to anticancer agents.

Aim. To describe the main genetic mutations and their impact on treatment prognosis, diagnosis and course of colorectal cancer.

Materials and methods. A systematic literature review of scientific databases Cochrane, PubMEd, MedLine, Elsevier was carried out. For the main search, the main search terms are formulated: colorectal cancer, mutations in colorectal cancer, molecular genetic studies in colorectal cancer, mutation of the KRAS gene. Also, a time range was set no later than 5 years, i. e. all articles published from 2017 to the current year.

Results. The main molecular changes in colorectal cancer are Chromosome instability, microsatellite instability, and abnormal DNA methylation. Suppressor genes, such as Ras, EGFR (Erb-B1), Erb-B2, TGF-alpha, and TGF-beta 1, are also of great importance.

Conclusion. Research that contributes to the understanding of the molecular basis of colorectal cancer helps in the early diagnosis of familial cancer, treatment prognosis and a personalized approach to patient treatment.

In the Russian Federation, the prevalence of bladder cancer is increasing from year to year. Currently, the problem of urine drainage after radical cystectomy is urgent. The most optimal medical, social and psychological rehabilitation in such patients is provided by orthotopic plastic surgery of the bladder. At the same time, it is necessary to use the terminal sections of the ileum. The article presents overview data on the key points of the creation of the neobladder, historical information on the development of techniques for creating a urinary reservoir, various methods of creating neocystis from the ileum. Data on the advantages and disadvantages of certain techniques are presented.

Background. D3 lymph node dissection remains controversial in colon cancer surgery.

Aim. To compare the short-term of D2 and D3 lymph nodes dissection for colon cancer.

Materials and methods. Design of the study – prospective randomize controlled study. Inclusion criteria: age over 18 years, colon adenocarcinoma cT3–4n0–2m0, patient consent to participate in the study. Exclusion criteria: distant metastases diagnosed preoperatively, cTis–T2, cT4b (pancreas, stomach, small intestine, ureter, bladder, kidney), emergent cases (limited to tumor perforation, acute bowel obstruction), history of previous chemotherapy or radiation therapy, synchronous or metachronous cancer, pregnancy or breastfeeding, refusal to participate in the study. withdrawal criteria were exploratory laparotomy/laparoscopy or other reasons for refusing resection.

Results. A total of 436 patients were included in the study no differences were found in the clinical characteristics of groups D2 and D3. In the D2 lymph node dissection group the incidence of unintentional vascular injuries was in 7 (3.2 %) patients, in the D3 lymph node dissection group – in 15 (6.9 %) patients (p = 0.12). The operating time increased by 30 minutes in D3 lymph node dissection group (p p = 0.42). Hartmann’s procedure was performed in 2 (0.9 %) patients in the D2 lymph node dissection group. Complications IIIb were recorded in 5 (2.3 %) and 9 (4.1 %) patients in lymph node dissection groups D2 and D3, respectively (p = 0.42). Anastomotic leakage was not observed in the D2 lymph node dissection group; in the D3 lymph node dissection group, it was diagnosed in 3 (1.4 %) patients (p = 0.25). postoperative multiple-organ failure (Iv) or mortality (v) were not observed. grade 3 quality of the specimen was observed in 160 (73.4 %) patients in the D2 lymph node dissection group, 163 (74.8 %) in the D3 lymph node dissection group (p = 0.79). The median number of lymph node harvested was 11 more in the D3 lymph node dissection group (p < 0.001). Apical lymph nodes were positive in 5 (2.3 %) patients in the D3 lymph node dissection group. There was no difference between the groups in R0 resection margin.

Conclusion. D3 lymph node dissection is safe in terms of short-term outcomes in the treatment of colon cancer.

Background. The established approach notably improving the therapeutic outcomes for locally advanced gastric cancer and gastroesophageal junction cancer, presently entails the amalgamation of perioperative chemotherapy aligned with the FLOT protocol and surgical intervention. However, this approach harbors limitations, as only half of the patient cohort successfully completes the entire prescribed course of drug therapy. The potential solution to this problem lies in the complete transfer of the chemotherapy volume to the preoperative period and the execution of total neoadjuvant chemotherapy with FLOT regimen.

Aim. Aim is to conduct a comparative assessment of the efficacy and safety between total neoadjuvant and perioperative chemotherapy with FLOT regimen for patients with locally advanced gastric cancer and gastroesophageal junction cancer.

Materials and methods. In a retrospective study we enrolled patients with histologically confirmed locally advanced gastric cancer and gastroesophageal junction cancer meeting clinical stage criteria T2–4 and N0–3, without of distant metastases, treated between 2014 and 2020 at Federal State Budgetary Institution “N. N. Blokhin National Medical Research Center of Oncology” оf the Ministry of Health of the Russian Federation and Moscow City Oncologic Hospital No. 62 Department of Healthcare of Moscow. Participants in the control group underwent 8 courses of perioperative chemotherapy (4 preoperatively and 4 postoperatively), while those in the experimental group received 8 courses of total neoadjuvant chemotherapy. Both groups received drug therapy according to the FLOT protocol: 5-fluorouracil 2600 mg/m² , intravenous drip, over 24 hours, leucovorin 200 mg/m² , intravenous drip, oxaliplatin 85 mg/m² , intravenous drip, docetaxel 50 mg/m² , intravenous drip, on day 1, with a 14-day intercourse interval. The primary endpoint was one-year progression-free survival.

Results. In the study included 187 patients. Participants were divided into two groups: 95 in the total neoadjuvant chemotherapy group and 92 in the perioperative chemotherapy group. The one-year progression-free survival was higher in the total neoadjuvant chemotherapy group at 79 %, compared to 68 % in the perioperative chemotherapy group (HR 0.54, 95 % confidence interval 0.32–0.9, p = 0.02). Median disease-free survival was 27.2 and 19.5 months in the neoadjuvant and perioperative chemotherapy groups, respectively. The tolerability of the entire planned drug treatment regimen was superior in the total neoadjuvant chemotherapy group, reaching 88.4 %, as opposed to 57.6 % in the perioperative chemotherapy group (p = 0.0001).

Conclusion. Among patients with locally advanced gastric cancer and gastroesophageal junction cancer, the application of total neoadjuvant chemotherapy according to the FLOT protocol, administered over 8 courses, demonstrated enhanced one-year progression-free survival and improved tolerability of the entire planned treatment regimen.

Background. Retrorectal tumors are a rare group of tumors that can be benign or malignant in origin; in most cases, they are asymptomatic. They mainly arise in the presacral space, which is limited by Waldeyer’s fascia posteriorly, the rectal fascia proper anteriorly, the ureters and lateral ligaments of the rectum laterally, the levator ani muscles and coccyx inferiorly, and the transition of the pelvic peritoneum between the second and third sacral segments superiorly. Magnetic resonance imaging (MRI) is crucial for diagnosis and surgical planning. Most retrorectal tumors require surgical treatment without preoperative biopsy. Here, we present a case of a retrorectal cystic hamartoma that was treated with surgery.

Clinical case. Patient N., 45 years old, presented with suspected pelvic malformation. The patient reported experiencing pain in the sacrum area since May 2023, with no history of trauma. She sought medical help at a local polyclinic, where an ultrasound of the pelvic organs revealed a pelvic mass. The patient was then referred to an oncologist at the Multidisciplinary Clinical Medical Center “Medical City”. Physical examination showed no specific features, except upon rectal examination, where a non-displaced tumor measuring up to 2 cm was palpated along the posterior rectal wall. MRI of the pelvic organs confirmed the presence of a mass behind the lower ampullary rectum. Surgical treatment was subsequently performed, and the diagnosis of teratoma was confirmed through morphological and immunohistochemical studies.

Conclusion. Early comprehensive diagnostics and an experienced surgical team are key factors for successful treatment of patients with retrorectal tumors.

Placental site trophoblastic tumor (PSTT) is а rare form of gestational trophoblastic neoplasia (GTN), accounting 0,2 % of total cases of GTN. PSTTs occur in women of childbearing age and most of them have strong desire to preserve fertility. PSSTs are tumors with unpredictable biological behavior, high chemo-resistance and possibly fatal outcome in case of metastatic disease.

Hysterectomy is the primary treatment of choice in early disease. We report a rare clinical case of fertility sparing treatment for PSTT.