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We discuss the operating principles of the apertureless scanning near-field optical microscope (ASNOM), in which the probe acts as a rod antenna and its electromagnetic radiation plays the role of the registered signal. The phase and amplitude of the emitted wave vary depending on the ‘grounding conditions’ of the antenna tip at the sample point under study. Weak radiation from a tiny (2–15 μm long) tip is detected using optical homo- and heterodyning and the nonlinear dependence of the tip polarizability on the tip–surface distance. The lateral resolution of ASNOMs is determined by the tip curvature radius (1– 20 nm), regardless of the wavelength (500 nm–100 μm). ASNOMs are shown to be capable of providing a surface optical map with nanometer resolution and carrying out spectral- and time-resolved measurements at a selected point on the surface.

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AIM: to evaluate the early and long-term results of emergency two-stage surgical procedures in patients with sigmoid colon cancer complicated by decompensated bowel obstruction.PATIENTS AND METHODS: the cohort study included 112 patients with sigmoid colon cancer complicated by bowel obstruction that underwent emergency two-stage surgical procedures in general surgical and coloproctological units in 2011-2017. The group 1 (n=60) included patients who, at the first stage, underwent Hartmann’s procedure, at the second stage – stoma reversal. The group 2 (n=52) included patients with a loop colostomy at the first stage and radical elective surgery as a second stage. The comparative analysis between the groups was carried out according to the following criteria: the type of surgery, the type of intestinal stoma, the rate and type of postoperative complications, postoperative mortality, resection status (R0/R1), the number of removed lymph nodes, the rate of adjuvant polychemotherapy (PChT).RESULTS: postoperative mortality in the group 1 was 3.33% (n=2) and occurred after the first main stage (Hartmann’s procedure), there were no deaths in group 2 (p=0.28). The procedures in group 2 fully met the criteria of oncological radicalism based on the number of lymph nodes examined and resection status (p<0.0001 and p<0.0001, respectively). Three-year overall survival at stage IIB in group 1 was 44.4% vs 75.2% in group 2 (p<0.0001); with IIIB in the 1st group – 60.3% vs 68.2% in group 2 (p=0.034); at IIIС in the 1st group – 35.7% vs 60.7% in the 2nd group (p=0.009). The 3-year disease – free survival at stage IIB in the 1st group was 41.7% vs 68.8% in the 2nd group (p<0.0001); with IIIB in the 1st group – 53.6% vs 64.5% in group 2 (p=0.036); at IIIС in the 1st group – 33.2% vs 60.8% in the 2nd group (p=0.023).CONCLUSION: for sigmoid colon cancer complicated by decompensated obstruction, in general hospitals the stage treatment with the colostomy at the first stage is preferable.

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.