Objective: analysis of the immediate and long-term results of surgical treatment of patients with lymph node (Ln) involvement in recurrent ovarian cancer (OC), as well as the search for prognostic factors for progression-free survival (PfS) and overall survival (OS).

Materials and methods. The retrospective analysis included patients under the age of 75 who underwent surgery for recurrence of OC with Ln involvement at n.n. Blokhin national medical Research Center of Oncology in the period from 2005 to 2020. All patients had previously received combined treatment due to a primary diagnosis of OC. Exclusion criteria: the presence of concomitant pathology in the decompensation phase, primary multiple malignant tumors and recurrences of non-epithelial ovarian tumors. The analysis of the main operational characteristics, the frequency of postoperative complications according to Clavien–Dindo within 30 days after surgery, PfS, OS, as well as parameters affecting the long-term results of treatment were performed.

Results. The study included 123 patients: a cohort of isolated lesions of the Ln (n = 65) and a group of combined recurrence in the Ln and other anatomical locations (n = 58). The frequency of complete cytoreduction was significantly higher in the group of patients with isolated recurrence in the Ln: 86.62 % versus 53.4 % in patients with combined relapse, p <0.0001. The median duration of the operation was also significantly higher in patients with combined recurrence: 245 min versus 180 min in a cohort of patients with isolated recurrence in the Ln, p <0.0001. Postoperative complications of grade III B were more often observed in the group of combined recurrence: 6.8 % versus 1.5 % in the group of isolated recurrence in the Ln, p = 0.148. none of the patients in the group of isolated recurrence in the Ln had postoperative mortality, while in the group of combined recurrence 2 (3.4 %) patients died after surgery from developed complications. In patients with isolated recurrence in the Ln and combined recurrence of OC, the median PfS was significantly higher when complete cytoreduction was achieved: 31.0 months and 18.0 months versus 10.0 months and 9.0 months with incomplete repeated cytoreduction, p <0.0001. In patients with isolated recurrence in the Ln and combined recurrence of OC, the median OS was identically significantly higher when complete repeated cytoreduction was achieved: 97.0 months and 60.0 months versus 34.0 months and 27.0 months with incomplete cytoreduction, p <0.0001.

Conclusion. Surgical treatment of recurrence of OC is justified only if it is possible to achieve complete cytoreduction and platinum-sensitive type of recurrence of OC. Low grade tumor, platinum-sensitive type of recurrence, absence of marker recurrence of OC, isolated recurrence in Ln, complete repeated cytoreduction and lymphodissection were identified as predictors of PfS in multivariate analysis. The following factors had an independent favorable effect on OS in multivariate analysis: low tumor grade, platinum-sensitive type of recurrence, satisfactory overall status on the ECOg scale (0–1 points) at the time of detection of relapse, isolated recurrence in the Ln and complete repeated cytoreduction.

Background. Circulating tumor DnA (ctDnA) may act as a potential biomarker for predicting disease progression in patients with colorectal cancer (CRC), which are radically cured or receiving chemotherapy.
Objective: to evaluate the sensitivity of the investigated ctDnA detection assay and quantify the concordance of genomic alterations between ctDnA and matched primary tumor tissue of patients with CRC.
Materials and methods. we included patients with histologically confirmed stage I–Iv CRC treated in n.n. Blokhin Cancer Research Center from 2016 to 2021. DnA was purified from tissue samples using QIAamp DnA formalin-fixed paraffin-embedded (ffPE) Tissue Kit (QIAgEn, germany). next-generation sequencing (ngS) technique was used to detect genetic mutations in primary tumor. ctDnA mutations were detected by droplet digital PCR.
Results. The sensitivity of platform (assay) for detecting genetic alterations in tissue samples was 97.82 %; in ctDnA – 51.20 % for all stages and 64.5 % for stage Iv CRC. Across eight genes (KRAS, TP53, APC, PIK3CA, BRAF, FBXW7, MB21D2, and SMAD4) concordance between primary tumor and ctDnA was 69.4 % (95 % CI 62.2–76.0). Sensitivity for all stages is 51.2 % (95 % CI 45.8–56.6), for metastatic CRC 64.5 % (95 % CI 53.3–74.5). The concordance across all genes was 65.4 % (95 % CI 57.1–73.1) and 83.8 % (95 % CI 69.6–92.9) for stage I–III and stage Iv CRC, respectively. The concordance rate between ctDnA and primary tumor tissue for KRAS alterations across all stages and stage Iv CRC was 78.3 % (95 % CI 66.7–87.3) and 90.9 % (95 % CI 64.7–99.0), respectively. with increasing tumor stage (T), the number of matches raised across all genes with the highest number observed in nx category.
Conclusion. The study indicates high concordance between tumor tissue and ctDnA, especially for KRAS and BRAF genes in patients with metastatic CRC, suggesting the clinical utility of ctDnA testing as a minimally invasive method and alternative to tissue biopsy.

Background. Currently available chemoradiotherapy regimens for distal rectal cancer often ensure complete regression of the tumor and lymph node lesions. Therefore, patients with a complete clinical response can be managed with a “watch and wait” (ww) strategy.
Objective: to evaluate 2-year overall and progression-free survival in patients with local and locally advanced rectal cancer with a complete clinical response who were managed with the ww strategy.
Materials and methods. we performed retrospective analysis of treatment outcomes in patients with newly diagnosed, histologically verified, stage II–III, mrT1–2n1–2m0, T3–4n0–2m0 (within 0–10 cm of the anal verge), and mrT2n0m0 (within 0–5 cm of the anal verge) rectal cancer who had demonstrated complete clinical response to chemoradiotherapy. mandard tumor regression grade (TRg1–2) (assessed using magnetic resonance imaging of the pelvis) and palpatory/visual signs of residual tumor (assessed by digital examination and colonoscopy) were the main parameters evaluated. Overall and disease-free survival was analyzed using the Kaplan–meier method.
Results. Twenty-seven patients with a complete clinical response were assigned to the ww group. mRI scans of the pelvis demonstrated that 5 patients (18.5 %) had TRg1, whereas 22 patients (81.5 %) had TRg2. T-downstaging after therapy was observed in 21 participants (77.7 %). n-downstaging was registered in all 14 patients (100 %) with regional lymph nodes affected. median follow-up time was 41 months (range: 25–114 months). Two individuals (7.4 %) developed progressive disease. Both of them had lengthy tumors as demonstrated by digital examination, colonoscopy, and magnetic resonance imaging; they immediately underwent radical surgery. The two-year overall and disease-free survival rates were 100 % and 92.6 %, respectively.
Conclusion. The ww strategy with active dynamic follow-up is safe for the management of patients with local and locally advanced middle and lower rectal cancer, provided that inclusion/exclusion criteria are adhered to and patients are carefully followed-up in specialized centers.

Objective: to compare short-term and long-term treatment outcomes between patients with lower and middle rectal cancer with complete clinical and pathomorphological response after comprehensive treatment.
Materials and methods. we performed retrospective analysis of treatment outcomes in patients with lower and middle rectal cancer. The experimental group included 27 patients with complete clinical response, whereas the control group comprised 31 patients with complete pathomorphological response (ypT0n0m0) who had undergone total mesorectal excision following neoadjuvant therapy. The main evaluated parameters included postoperative complications, proportion of R0 resections, proportion of sphincter-preserving surgeries, 2-year overall survival, and progression-free survival.
Results. At a median follow-up time of 41 months (range: 25–114 months), 2 patients from the experimental group had progressive disease registered 18 and 19 months after treatment initiation; both patients underwent abdominoperineal extirpation of the rectum. The remaining 25 patients had sphincter sparing surgeries. At a median follow-up time of 48 months (range: 24–101 months), one patient was found to have liver metastasis 5 months following treatment initiation. He underwent simultaneous surgery that included low anterior resection of the rectum and liver resection and had no postoperative complications. In the group of surgical treatment, all patients underwent radical surgeries (R0), including those with permanent stoma formation (n = 11; 35.5 %) or preventive stoma formation (n = 20; 64.5 %) with subsequent bowel repair. The 2-year overall survival rate was 100 % in both groups. The 2-year progression-free survival rate was 92.6 % in the experimental group and 96.8 % in the control group (p = 0.473).
Conclusion. The watch and wait strategy with active dynamic follow-up is a safe alternative to surgery in patients with complete clinical response after neoadjuvant therapy, since it ensures the results equivalent to those in patients with complete pathomorphological response.

The purpose of the systematic review is to summarize the data regarding safety and efficacy of stereotactic body radiation therapy in patients with oligometastases of colorectal cancer to the liver.
Published scientific articles on the topic were identified by searching the databases mEDLInE, Pubmed, EmBASE. The review includes publications reporting on the results of treatment of patients undergoing stereotactic radiation therapy for. The systematic review includes all retrospective and prospective studies found over the past 15 years with at least 10 patients with liver metastases of colorectal origin included and standardized methodology of radiation therapy. We included into the review 20 studies comprising 919 patients. Comparative analysis was complicated because of the absence of control groups in all of the studies. moreover, 16 studies were single-center with heterogeneous groups of patients and various regimens of stereotaxic radiation therapy. Despite this, the researchers achieved 60–100 % rates of one-year local control, 56–100 % one-year overall survival with median overall survival up to 45 months and the number of clinically significant complications less than 10 %.
From our point of view, the results of published studies support the safety and efficacy of stereotactic radiation therapy in patients with colorectal cancer and oligometastatic liver disease. we consider stereotactic body radiation therapy to be one of the local control options in case of careful patient selection and the use of modern radiation therapy options. further randomized controlled trials are needed.

The aim of the work is to analyze all available literature data on the role of secondary cytoreduction, its effectiveness and safety in the recurrence of ovarian cancer (ОС) with isolated lymph node (LN) lesion.
The importance and place of secondary cytoreduction in the combined treatment of recurrent ОС is one of the most controversial topics. The lesion of the LN in recurrent Ос varies from 12 % to 37 %, but an isolated recurrence in the LN is a very rare occurrence, about 5 %. The most common localization in recurrent ОС with isolated LN lesion is the paraaortic LN.

The results of this literature review suggest that isolated Ln lesion should be clearly distinguished from recurrence at other sites (such as peritoneal and parenchymal), since patients with isolated recurrence in the LN have a relatively indolent course of the disease. The frequency of complete cytoreduction according to the available data of retrospective studies reaches 100 %. Paraaortic and pelvic lymph node dissection without a macroscopically detectable residual tumor in combination with postoperative systemic chemotherapy leads to improved survival rates compared only with systemic drug treatment of patients with isolated LN lesion in recurrent ОС. median survival from the moment of relapse detection and overall survival varies from about 2.5 to 4 years and >5 years, respectively. Systemic paraaortic and pelvic lymph node dissection is preferable compared to selective lymphadenectomy, as it is accompanied by an increase in progression-free survival, although it doesn’t significantly prolong overall survival.