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Оbjective. To assess the sensitivity of CT pneumogastrography in determining the T-stage and yT-stage. Materials and methods. This is a prospective, single-center study that included 267 patients with a histologically diagnosed stomach cancer who received treatment at the N.N. Petrov National Medical Research Center of Oncology from 2015 to 2018. 162 (60.7%) patients underwent preoperative chemotherapy. All patients underwent surgery: 22 in the volume of proximal subtotal gastrectomy, 95 in the volume of distal subtotal resection, 123 in the volume of gastrectomy, and 27 in the volume of endoscopic dissection. All patients underwent staging computed tomography at the preoperative stage according to a single protocol - CT pneumogastrography on a 64-slice X-ray computed tomography. The sensitivity of the method in assessing the depth of invasion was calculated separately for patients without preoperative chemotherapy (T-stage) and for patients who underwent preoperative chemotherapy (уT-stage) by comparison with pathological data. Results. The sensitivity indicators of CT pneumogastrography for patients without preoperative chemotherapy were: for T1a – 80.6%, T1b – 72.7%, T2 – 80.0%, T3 – 88.0%, T4a – 83.3%, T4b –100%. The sensitivity indicators of CT pneumogastrography for patients receiving preoperative chemotherapy were: for уT2 – 65.2%, уT3 – 83.5%, уT4a – 83.9%, уT4b – 75.0%. It is difficult to restore locally advanced gastric cancer with a depth of invasion cT2 – cT4b in the category yT0, yT1a, and yT1b after preoperative chemotherapy due to the persisting pathological tissue with impaired differentiation of all layers of the stomach wall, which is pathomorphologically a large fibrous tissue. Сonclusion. CT-pneumogastrography demonstrates high diagnostic indicators in determining the T-stage and yT-stage of gastric cancer.

The advantages of computed tomographic pneumogastrography with the possibility of three-dimensional visualization and virtual gastroscopy in diagnosing gastric cancer are considered. The study included 479 patients with histologically diagnosed gastric cancer who were treated at the National Medical Research Center of Oncology named after N.N. Petrov from 2011 to 2018. 232 patients received preoperative chemotherapy. All patients underwent surgery: 70 —in the volume of endoscopic dissection, 40 — proximal subtotal resection, 166 — distal subtotal resection, 203 — gastrectomy. All patients at the preoperative stage underwent staging computed tomography on a 64-slice X-ray computed tomograph: 208 patients underwent computed tomography according to the standard protocol without targeted preparation of the stomach for the study, 271 patients with targeted preparation of the stomach for the study according to the computed tomographic pneumogastrography protocol. The sensitivity of the computed tomography in assessing the T-stage was assessed by comparison with pathomorphological data. Of the 208 patients who underwent computed tomography according to the standard protocol, a gastric cancer was detected in 111 (53.4%), out of 271 patients who underwent computed tomography pneumogastrography, a gastric cancer was detected in 267 (98.52%), which is a statistically significant difference in comparing computed tomography methods (Pearson, χ ² — 144.223, df = 1; p < 0.001). There are statistically significant differences when comparing computed tomography according to the standard protocol and computed tomographic pneumogastrography in detecting gastric cancer for all tumor categories: T/yT1 — 8.2 and 94.4% (Pearson, χ ² — 99.205, df = 1; p < 0.001), T/yT2 — 47.8 and 100% (Pearson, χ ² — 24.681, df = 1; p < 0.001), T/yT3 — 72.3 and 100% (Pearson, χ ² — 33.114, df = 1; p < 0.001), T/yT4 — 90.0 and 100% (Pearson, χ ² — 4.789, df = 1; p = 0.029) respectively. There are also statistically significant differences when comparing the sensitivity of computed tomography according to the standard protocol and computed tomographic pneumogastrography in determining tumor invasion for all tumor categories: T/yT1 — 0 and 69.4% (Pearson, χ ² — 67.880, df = 1; p < 0.001), T/yT2 — 26.1 and 71.1% (Pearson, χ ² — 11.666, df = 1; p < 0.001), T/yT3 — 32.9 and 84.6% (Pearson, χ ² — 54.900, df = 1; p < 0.001), T/yT4 — 73.3 and 95.7% (Pearson, χ ² — 7.916, df = 1; p = 0.005) respectively. In general, the sensitivity of the computed tomography according to the standard protocol for determining the T-stage of gastric cancer was 28.4%, computed tomographic pneumogastrography — 77.1% (Pearson, χ ² — 113.505, df = 1; p < 0.001). Computed tomographic pneumogastrography with the possibility of three-dimensional visualization and virtual gastroscopy significantly increases the indicators of the effectiveness of diagnosing gastric cancer — both early forms (category T1) and with deeper invasion (categories T2–T4), demonstrates high sensitivity in determining T/yT-stages.

Objective: to assess the accuracy of CT densitometry as a method for measuring the X-ray density of an object, as well as factors affecting the measurement results.Material and methods. X-ray density indicators were measured in various zones of phantoms containing drinking water with a volume of 0.5, 1.0, 1.5, and 2.0 l, as well as 5 identical vials with a capacity of 0.25 l with iopromide solutions with a concentration of 0, 5.2, 7.6, 10 and 20 ml/l. For each phantom, from 5 to 10 scans were made, followed by measuring the X-ray density of the contents in the central zone closest to the CT system center of rotation, and two zones located to the periphery from the center of rotation.Results. As a result of analyzing the values of measuring X-ray density in various parts of water-containing phantoms, an increase in the values of X-ray density near the center of rotation of the system and in the upper sections of the phantom with an increase in the volume of phantom was revealed. In the lower peripheral zone in 1.5 and 2.0 liter phantoms, the X-ray density was unchanged. The overestimation of the X-ray density values of the CT images of phantoms with small and large concentrations of iopromide during co-scanning compared with separate scanning was determined.Conclusion. CT densitometry is a highly sensitive method for measuring the X-ray density of image elements, however, the X-ray density of neighboring structures and the location of this zone relative to the center of rotation of the CT system affect the CT densitometry results. During jointly scanning phantoms of various densities, their mutual influence and the appearance of specific artifacts in the form of dark stripes on the lines of continuation of horizontal levels and “pulling up” the edges of these horizontal contrast levels to the center of rotation of the system were noted.

For treatment of metastatic lung lesions there was used the method isolated chemoperfusion of the lung in combination with metastasectomy. The study includes 74 patients with metastases in the lungs who underwent 101 normothermal isolated chemoperfusion of the lung: of these 38 (37,6%) with melphalan and 63 (62,4%) with cisplatin without lethality. In the early postoperative period 1 (1,4%) patient died due to postperfusion lung edema. The period of observation of patients ranged from 2 to 99 months (median 29.3 months). Of 74 patients 53 (71,6%) patients are alive, 2 (2,7%) patients died from causes unrelated to the underlying disease. 43 (58,1%) patients showed progression of disease, what in 18 (41,9%) of them was the cause of death. Repeated appearance of metastases in perfused lung was detected in 30 (40,5%) patients. A 5-year disease-free (in the lungs) and observed survival of patients after isolated chemoperfusion of the lung with metastasectomy was 45% (median 46 months) and 59% (median not reached) respectively. There were established predictors of effectiveness of isolated chemoperfusion of the lung with metastasectomy: DFI13 months, ≤5 metastatic nodes in the lungs, the size of the largest metastasis in the lungs ≤20 mm, intralobular location of metastases in the lungs as well as the time of doubling the volume of metastases64 days for chest computed tomography.

It is performed univariate and multivariate analysis of factors affecting the overall cancer survival of 613 patients of 70 years or older radically operated for non-small cell lung cancer. It is found that the main independent predictors of survival are T and N categories. These variables retain their importance in the overall multivariate model both types of survival, and the variable T - in separate multivariate models for samples stratified by category N. The presence of diabetes dramatically reduced both types of survival. Among patients without regional metastases women had a higher survival rate. The age of the operated patients older than 70 years had no significant independent effect on survival.

With a wide excision of skin melanoma localized in areas of the sternum, the sacrum or on the back near body's midline there is often occurred a problem of closing appeared defect. Local tissues are insufficient and performing of free plastic is undesirable because of the unfavorable conditions of the free flap engraftment due to the peculiarities of transplant bed and difficulties of immobilization and fixation of the flap. For exactly such surgical situations we have developed a method of reliable replacement of appeared defects by two adjacent symmetrical rotary flaps.

One-year lethality was studied in 613 patients older than 70 years who underwent surgery for lung cancer for the period of 1970-2002. During the first year after surgery 166 patients died (27.1%) and besides from the generalization of the disease - 92.2%, from other causes - 7.8%. The highest rate of one-year lethality was observed after pneumonectomy (39.4%), the lowest one - after lung margins resection (16.5%). It was found that the most important factor in one-year lethality rate was N2 lymph node status. Risk of dying from the generalization of the disease during the first year sharply increased in group of patients underwent extended and combined pneumonectomy (one-year lethality of 52.6% and 57.1%, respectively), pneumonectomy with N2 (56,0%), lobectomy in peripheral cancer with metastases of N2 level (63,6%), especially when the amount of the tumor was more than 5 cm (83.3%).

It was found that melanomas of the skin of the head and neck, compared to the trunk and limbs, were characterized by a greater proportion of men, an older average age of the patients, high frequency spindle cell tumors, more frequent synchronous distant metastasis and worse survival. Melanomas, which are localized on the skin of the neck and scalp, have similar aggressive clinical course and are characterized by worse overall and disease-free survival than skin melanomas on the trunk and limbs. However, melanomas of the skin on the ear and face proceed more favorably as compared to skin melanomas of the scalp and neck. Multivariate regression analysis using Cox models showed that the melanoma of the head and neck Breslow tumor thickness was the strongest predictor of overall survival. For skin melanomas of the neck and scalp Breslow tumor thickness was the only significant independent factor for overall survival. In melanoma, skin and ear predictors of survival are: sex, age and tumor thickness. In skin melanomas of the face and ear predictors of survival were sex, age and tumor thickness.

The growth rates of local recurrences and in-transit metastases of skin melanoma were assessed in 271 patients. Median growth rate in the course of chemotherapy was 0.02 a day--1 which corresponded to a doubling time of 34.7 days. Median survival time for patients with local recurrences and in-transit metastases was 22.6 months, 12-month survival--70.1%, 5-year--19.6% and 10-year--9.9%. Growth rate appeared to be the most significant prognostic factor; similarly important were tumor volume, relapse-free interval, tumor mitotic rate, site and number of recurrences. The following additional characteristics of tumor growth rate have been suggested: maximum growth rate and doubling time limit, to assess the rates of secondary tumor focus development.

The time between primary lesion excision to lymphadenectomy for cutaneous melanoma was determined in 550 patients. Maximum relapse-free interval was 17.8 years, mean--16.4 months, with median time of 6.2 months. We used retrospective multivariate analysis of the time for metastases to the regional lymph nodes with such variables as sex, age at tumor presentation, site, volume of tumor or largest nodular metastasis, number of involved nodes, satellites, Breslow thickness, ulceration, epithelioid-cell presence, pigmentation, mitotic index, spontaneous tumor regression, invasive growth (Clark), and lymphoid infiltration. A retrospective univariate analysis involved such significant predictors as spontaneous tumor regression (p(0.00001), logarithm of primary tumor volume (p=0.0005), sex (p=0.0007), tumor site (p=0.008), satellites (p=0.011), and Clark's index (p=0.025). Cox's multivariate analysis established a relationship between relapse-free time and such variablesas spontaneous tumor regression (p(0.00001), logarithm of primary tumor volume (p=0.0006), tumor site (p=0.016), logarithm of volume of largest nodular metastasis (p=0.019), and sex (p=0.032).

The dynamics of growth of skin melanoma metastases to the lung versus chemoimmunotherapy regime has been assessed quantitatively. Natural course of such pathology at advanced stages was found to correspond to the exponent. An analytical procedure for plotting graphs was suggested, which will allow to estimate the kinetic characteristics of tumor growth. This in turn can be used as an indicator of therapy efficacy.

The surgical bypass of v. azygos and v. pulmonalis sup. dext. to decompress the lesser circulation after extensive resections of the lung is elaborated. The operation was performed on 21 patients for cancer of the right lung, and in one patient with bilateral disease. The shunting followed pneumonectomy in 11 cases, the lower bilobectomy in 7, the upper lobectomy in 2. In 1 patient the operation was performed after successive left-sided lower lobectomy and right-sided upper lobectomy. The shunting reduced the middle pressure in the lung artery by 13,9-21,0% of the postresection level. The bypass did not cause statistically significant decrease of the oxygenation in the arterialized capillary blood.