Colorectal cancer (CRC) is the most frequently occurring malignancy in the world. However, the mortality from CRC can be reduced through early diagnostics, selection of the most effective treatment, observation of the therapy success, and the earliest possible diagnosis of recurrences. A comprehensive analysis of genetic and epigenetic factors contributing to the CRC development is needed to refine diagnostic, therapeutic, and preventive strategies and to ensure appropriate decision making in managing specific CRC cases. The liquid biopsy approach utilizing circulating markers has demonstrated its good performance as a tool to detect the changes in the molecular pathways associated with various cancers. In this review, we attempted to brief the main tendencies in the development of circulating DNA and RNA-based markers in CRC such as cancer-associated DNA mutations, DNA methylation changes, and non-coding RNA expression shifts. Attention is devoted to the existing circulating nucleic acid-based CRC markers, the possibility of their application in clinical practice today, and their future improvement. Approaches to the discovery and verification of new markers are described, and the existing problems and potential solutions for them are highlighted.

Background. Currently, perioperative chemotherapy is the standard treatment option for resectable gastric cancer (GC ) at stages higher than T1. Preoperative chemotherapy was shown do not adversely affect the course of the postoperative period in gastric cancer patients. However, approximately 60 % of radically operated patients complete adjuvant chemotherapy. In this regard, the problem arises of postponing all courses of chemotherapy for operable gastric cancer to the preoperative period.The purpose of the study was to analyze short-term efficacy and toxicity of total neoadjuvant chemotherapy with FLOT regimen in patients with resectable gastric cancer.Material and Methods. Since 2020, the Research Cancer Institute of Tomsk National Research Medical Center has been conducting a pilot study, which included 25 patients with resectable gastric cancer (T2–4N0–2M0) who received 8 cycles of neoadjuvant chemotherapy with FLOT regimen followed by radical surgery (gastrectomy or distal subtotal resection of the stomach).Results. Preoperative chemotherapy was completed in 25 (100 %) patients. Side effects that occurred during chemotherapy did not require cancellation or interruption of treatment and reduction in the initial dose of drugs. The most common adverse events were emetogenic reactions (92 %), peripheral neuropathy (60 %), and neutropenia (48 %). All patients had no greater than grade II toxicity, which was reversed with standard maintenance therapy. Radical surgeries were performed 6 weeks after completion of chemotherapy cycle 8. There were no significant postoperative complications (grade III or higher according to the Clavien–Dindo scale) and deaths. The histological examination revealed pathological response of TG R2–3 grade in 21 (84%) patients. Downstaging in both T and N categories was found in 13 (52%) patients.Conclusion. Eight cycles of total neoadjuvant chemotherapy for resectable gastric cancer demonstrates high efficacy, moderate toxicity, and do not adversely affect the course of the perioperative period.

Colorectal cancer is the third most common cancer worldwide, making lymph node recovery critical for treatment decisions and prognosis. Within the colorectal tumor microenvironment, the metabolic programming of tumor-associated macrophages (TAMs) can drive both pro- and anti-tumor responses, yet the specific glycolytic pathways governing their pro-metastatic conversion present promising therapeutic targets. This study investigated the role of glycolysis activating enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) in mediating TAMs metabolic polarization, and its potential as a therapeutic target. PFKFB3 expression was found to be predominant in TAMs in CRC tumor samples. Lipidomic analysis performed by HPLC-MS/MS revealed that PFKFB3 inhibition altered glycerophospholipid metabolism (p = 6.13 × 10⁻¹⁰), and shifted TAMs toward sphingolipid-mediated immunosuppressive metabolism. PFKFB3 activity was associated with a specific reduction in asparagine availability, potentially pointing to a targeted reprogramming of amino acid metabolism supporting distinct TAM functions under conditions of intra-tumoral metabolic stress. These findings highlight PFKFB3 as an essential regulator of TAMs pro-tumoral metabolism in CRC, particularly in colon cancer.

The majority of colorectal cancer patients (CRCPs) develop tumors on the background of “metabolically healthy obesity” or metabolic syndrome. The aim of the work was to study the levels of matrix metalloproteinases (MMPs) and heat shock proteins (HSPs) on the surface of blood plasma CD9-positive and FABP4-positive small extracellular vesicles (sEVs) from CRCPs depending on metabolic status and tumor angiogenesis, as well as to evaluate the sEVs markers as predictors of the effectiveness of thermoradiotherapy. In CRCPs, compared with patients with colorectal polyps (CPPs), the proportion of triple positive EVs and EVs with the MMP9+MMP2-TIMP1+ phenotype increased significantly among FABP4-positive EVs (adipocyte-derived EVs), which in general may indicate the overexpression of MMP9 and TIMP1 by adipocytes or adipose tissue macrophages in CRCPs. The results obtained have prospects for use as markers to clarify cancer risk in CPPs. One can assume that for CRCPs with metabolic syndrome or metabolically healthy obesity, it is the FABP4+MMP9+MMP2-TIMP1- population of circulating sEVs that is the most optimal biomarker reflecting tumor angiogenesis. Determining this population in the blood will be useful in monitoring patients after treatment for the early detection of tumor progression. CD9+MMP9+MMP2-TIMP1- and MMP9+MMP2-TIMP1+ subpopulations of circulating sEVs are the most promising predictors of the efficacy of thermoradiation therapy because their levels at baseline differ significantly in CRCPs with different tumor responses.

The purpose of the study was to assess the short-term effcacy and tolerability of neoadjuvant chemotherapy (NAC) in colorectal cancer (CRC) patients with isolated liver metastasis.Material and Methods. Since 2020, a pilot study including 23 CRC patients with liver metastasis has been conducted at the Abdominal Cancer Department of the Cancer Research Institute (Tomsk, Russia). The combined treatment modality included 3 cycles of NAC according to FOLFOXIRI + cetuximab (20 patients with wtKRAS) and FOLFOXIRI + bevacizumab (3 patients with mtKRAS) regimens followed by simultaneous laparoscopic colorectal resection and open liver resection.Results. For liver metastases, the objective response rate reached 100 % (complete response: 8.7 %, partial response: 91.3 %). For the primary tumor, the objective response rate was 100 % (partial response). The overall NAC toxicity rate was 53.6 %. The major I–II grade toxicities included nausea/vomiting (27.5 %), polyneuropathy (10.1 %), skin reaction (10.1 %), hepatotoxicity (5.8 %), and corresponded to I–II grade. R0 resection was performed in all patients. Postoperative complications were observed in 19 (82.6 %) patients; of them 18 (78.3 %) had a febrile temperature (grade 1, according to the Clavien–Dindo classifcation) due to the use of bipolar coagulation during liver surgery, and 1 (4.4 %) patient developed a biliary fstula (3 A/B grade according to Clavien–Dindo). No postoperative death occurred. For liver metastasis, pathological complete response rate was 4.4 % (TRG1 according to Mandard); for the primary tumor, in most cases was TRG 3 – 87 %.Conclusion. Combined treatment modality, including NAC with FOLFOXIRI regimen and targeted therapy for CRC with liver metastases, is well tolerated, has a signifcant damaging effect on the tumor, and does not affect the course of the postoperative period. Further studies are required to assess the long-term treatment outcomes.

Hepatic resection has become the treatment of choice for metastatic colorectal cancer, and this treatment technique increases the five-year survival of cancer patients up to 40–58%. More recently, the criteria for resectability have been revised and expanded to include any patient in whom all metastatic deposits can be removed with a negative surgical margin and with sufficient residual liver parenchyma. Currently, resectability is determined mostly by the minimum functional liver remnant volume. Under this new paradigm, the number of patients with potentially resectable oncological process can be increased. However, there are no widely accepted concepts and criteria for resectability, which further complicates the choice of treatment methods and directly affects the patients’ survival. The literature search for this review was performed using PubMed, Cochrane Library, Google Scholar, and eLibrary systems. We included publications that characterized the modern possibilities of liver surgery aimed at increasing resectability and improving cancer outcomes in patients with colorectal cancer liver metastases.