The published data regarding radiation therapy of tumors treatment with ultrahigh dose rate radiation has been analyzed. In 2014, the authors, among whom the most mentioned are Vincent Favaudon and MarieCatherine Vozenin, named it the flash effect. Note, however, that a member of our laboratory, S.V. Kozin in the collaboration with ITEP researchers, back in 1984, having studied the reaction of a graft tumors and the mice skin after the proton irradiation with the ultrahigh and ordinary dose rates, concluded that: ‘... an increase in the radiation dose rate to ultrahigh, without significantly changing radiation reactions of tumors, leads to the protection of the mice skin, which is associated with the manifestation of the effect of radiation-chemical absorption of oxygen. Thus, under certain conditions of radiotherapy, one can expect to receive a therapeutic gain due to use the radiation with a high dose rate’. Consideration of the expediency and possibility of using a single irradiation with a dose rate of tens of Gy/s in radiation therapy of tumors is now given a special attention. It can be considered as established that less damage to the skin, lungs, intestines, and some other tissues occurs in this case in comparison with the usual dose rates used for the radiation therapy. Moreover, a number of studies indicate an increase in radiation damage to the tumors, or at least a much smaller decrease in the degree of their damage. The radiobiological mechanisms remain unclear. The effect itself is of undoubted clinical and experimental interest and justifies the conduct of experimental and clinical studies, as well as the need to take it into account when developing new equipment for radiation therapy and dosimetry accompanying the treatment process.

Purpose: To study the safety of ^99mTc-1-Thio-D-Glucose (^99mTc-TG) using, as well as its pharmacokinetics and dosimetric characteristics.
Material and methods: The pharmacokinetics of 99mTc-TG was studied in 12 patients with lymphomas. The study was performed after a bolus injection of 729 ± 102 MBq ^99mTc-TG. Whole body anterior and posterior planar imaging was performed at 2, 4, 6, and 24 hours post-injection. In addition, all patients underwent SPECT/CT scanning at 2 hours and only SPECT at 4 and 6 hours after injection. To determine the dynamics of ^99mTc-TG accumulation in organs and tissues, the corresponding regions of interest (ROI) were outlined on each of the scans. Absorbed doses were calculated using a specialized OLINDA/EXM 1.1 program using phantoms of adult women and men.
Results: The study showed that the administration of ^99mTc-TG is well tolerated by patients and is not accompanied by any side effects. The specified radiopharmaceutical has favorable dosimetric properties. Thus, in the present study, effective doses ranged from 5.0 to 9.8 mSv. SPECT/CT revealed high uptake of ^99mTc-TG in all nodular lesions detected according to standard diagnostic methods. There was also agreement between visualization of extranodal lesions using ^99mTc-TG SPECT/CT and standard diagnostic methods in all cases of the brain, neck, chest and abdomen lesions. In our study, the use of ^99mTc-TG SPECT/CT allowed us to detect a bone lesion that was not visualized on CT. This finding was an indication for an additional MRI examination, which confirmed a lymphoma lesion of the humerus. 2 hours after the injection of ^99mTc-TG, the tumor-background ratio reached 3.3 ± 1.2, then decreased to 2.30 ± 1.42 after 4 hours and then did not change significantly, so the optimal time for performing SPECT is 2 hours after the introduction of ^99mTc-TG.
Conclusion: ^99mTc-TG is well tolerated by patients and has favorable dosimetric properties. ^99mTc-TG SPECT/CT may become the only method for molecular imaging of lymphoma in patients living in countries and regions with limited or no access to PET.

Purpose: To develop algorithms for echographic differential diagnosis of soft tissue tumors containing fat tissue, the data of the complex examination were analyzed, including using various ultrasound techniques, including different types of dopplerography and compression elastography.
Material and methods: Echographic studies of verified histologically 221 (63  %) lipomas, 87 (24.8  %) liposarcoma, 43 (12.2 %) hemangioma and lymphangosis of different superficial localizations were performed on Hitachi HI Vision 900, Logiq-400, Aloka-650, Aloka-2000 with 5–13 MHz sensors.
Results: It has been established that ultrasonic elastography in a number of clinical situations can be a significant addition in the differentiation of lipomas and highly differentiated liposarcoma, as well as in determining the boundaries of diffuse tumors from adipose tissue. Diagnostic algorithms for differentiating tumors have been proposed.
Conclusions: Differential diagnosis of fat-containing soft tissue formations is very complex and requires a multiparametric approach in ultrasound diagnostics.

Purpose: The aim of our study was to study the possibilities of DW-MRI in the differential diagnosis of recurrent retroperitoneal highly differentiated and dedifferentiated liposarcomas (WLS and DLS respectively).
Material and methods: The study is based on the data of a retrospective study of 36 patients who underwent surgery on for retroperitoneal highly differentiated (n = 27) and dedifferentiated liposarcomas (n = 9). All patients received MRI of the abdominal cavity and pelvis without intravenous contrast enhancement with further assessment of size, shape, contours and structure. When analyzing DW-MRI and ADC maps, small soft tissue nodes were evaluated.
Results: Morphological studies were performed in all patients. The results of the qualitative analysis showed statistically significant differences in the differential diagnosis of WLS recurrences from DPS in the presence of septa and pseudocapsule (p = 0.0032 and p = 0.0028, respectively). The results of the study demonstrated differences in the ADC values in the solid component of recurrent tumors of WLS and DLS: the median ADC values in the WLS group were higher (1960×10^–6 mm²/s) than in the DLS group (1031×10^–6 mm²/s). The sensitivity of this sign in the differential diagnosis of WLS from DLS was 87.5 %, the specificity was 70 %.

Background: Comprehensive treatment of locally advanced cervical cancer (CC) requires the use of informative diagnostic methods to assess tumor size, extent of the tumor and other factors that determine prognosis of the disease.
Purpose: Determination of diagnostic opportunities of multiparametric magnetic resonance imaging (mpMRI) in the visualization of residual tumor and assessment of the main prognostic factors in patients with stage IB2-IIB cervical cancer (FIGO) after neoadjuvant chemotherapy (NACT).
Material and methods: Patients with stage IB2-IIB cervical cancer (n = 120) were prospectively enrolled in the study; they received NACT followed by surgical treatment or chemoradiotherapy (CRT). Patients underwent mpMRI before NACT and not later than 14 days after the 3rd course of NACT. To determine the diagnostic opportunities of mpMRI, MRI-data were compared with pathomorphological results. In the comparative analysis were included the following factors: residual tumor size (maximum diameter), depth of stromal invasion (mm), presence of parametrial invasion. Potential MRI-signs suggestive for lymphovascular invasion (LVI) of the parametrium were also assessed.
Results: Obtained MRI-data about the size of the residual tumor and the depth of stromal invasion showed statistically significant correlation with the results of pathomorphological study (p < 0.0001) — R² = 0.77 and 0.69, respectively. Difference value in measuring the maximum diameter of the residual tumor was on the average 2.52±6.76 mm. MRI sensitivity in the assessment of parametrial invasion was 71.4 %, specificity — 95.1 %, accuracy — 88.9 %, PVPR — 71.4 %, PVNR — 95.1 %. Potential predictors significantly associated with parametrial LVI were identified: parametrial edema (p = 0.001) and dilatation of parametrial vessels (> 3 mm) (p = 0.015). According to these factors was developed a mathematical model, which predicts the risk of having parametrial LVI before surgery in patients after NACT.
Conclusion: Multiparametric MRI is an effective technique in assessing the size of the residual tumor, depth of stromal invasion and parametrial invasion in patients with stage IB2-IIB cervical cancer after NACT. MpMRI makes it possible to assess potential signs, associated with parametrial LVI in patients with locally advanced cervical cancer.

The present review shows a modern view on the issues of differential ultrasound diagnosis of hyperechoic malignant tumors of the mammary glands. On clinical examples, the main ultrasonic semiotic signs of hyperechoic malignant structures were noted in comparison with the data of histopathological analysis.

Purpose: Determination of the effectiveness of using a vacuum fine-needle aspiration biopsy compared to fine-needle aspiration biopsy.
Material and methods: An original experimental sample has been developed for performing a vacuum fine-needle aspiration biopsy. Also in the course of the study, an improvement of the device was carried out, associated with the peculiarity of using high pressure (over –0.5 bar), consisting in throwing cytological material from the needle directly into the lumen of the syringe, and its distribution along the walls of the piston with impregnation with a separating tissue membrane. From January to November 2022, 118 vacuum fine-needle aspiration biopsy were performed using a modified technique.
Results: During vacuum fine-needle aspiration biopsy, it was possible to achieve the absence of uninformative cytological material (Bethesda 1) and the receipt of 4.2 % (n = 5) of the amount of atypia of indeterminate value, which indicates the effectiveness of this method.
Conclusions: 1. When performing vacuum fine-needle aspiration biopsy, the stage of taking cytological material is facilitated, which is associated with the creation of a high discharge and filling of the cytological material of the lumen of the needle, this feature contributes to fewer needle movements in the biopsy area and a decrease in the production of blood elements in the aspirate.
2. The use of high discharge does not affect the excessive traumatization of the thyroid parenchyma compared to fine-needle aspiration biopsy.
3. The ability to select the level of discharge depending on the data of multiparametric ultrasound examination, allows you to individualize the procedure.
4. The use of modification in the form of isolation of cytological material in a syringe reduces the loss of cytological material and increases the effectiveness of the technique.

The question of the need for routine preoperative drainage of the biliary tree in peripapillary tumor obstruction is still debatable.
We conducted a retrospective randomized single–center study, the first control point of which was to study the safety of percutaneous drainage, the second was the effect of preoperative drainage on the number of postoperative complications in pancreatoduodenectomy (PD).
The results of 85 Whipple’s PD for a tumor of the head of the pancreas were analyzed. Preoperative biliary drainage (PBD) was performed in 75 (88.2 %) cases and was represented by percutaneous transhepatic cholangiostomy. 10 (11.8 %) patients did not undergo PBD.
In the preoperative period, the level of plasma bilirubin and the severity of mechanical jaundice were assessed according to E.I. Galperin, 2014. The frequency of postoperative complications was assessed, both after performing PBD and after PD, the severity was graded according to the Clavien–Dindo scale.
The technical success of cholangiostomy was achieved in 100 % of cases, the clinical efficacy of PBD is represented by a significant decrease in serum bilirubin levels and a decrease in the severity of jaundice.
Complications of transcutaneous interventions on the biliary tree corresponded to III A of the Clavien– Dindo scale and did not affect the preoperative status.
Complications of PD among patients without PBD corresponded to classes IIIA and V of the Clavien–Dindo scale: failure of pancreatojejunostomy (30  %, 3 out of 10) with the formation of pancreatic fistula, complete or partial failure of hepaticojejunostomy (30 %, 3 out of 10). Infectious complications in the form of abdominal abscesses and suppuration of a postoperative wound were found in 20 % (2 out of 10).
In patients after PBD, PD complications corresponded to classes IIIA and IIIB of the Clavien–Dindo scale: partial failure of pancreatojejunostomy and pancreatic accumulations of the abdominal cavity (18.7 %), acute pancreatitis (12 %) and focal pancreatic necrosis (12 %), partial failure of hepaticojejunostomy (6.7 %). Abscesses of the abdominal cavity and retroperitoneal space, infection of the wound were noted in 14.7 %.
After PD, the mortality rate was 6 (7.1 %) cases, of which 3 (30 %, 3 out of 10) patients without PBD and 3 (4 %) patients with cholangiostomy.
Using contingency tables with the calculation of Fisher’s exact test and Pearson’s contingency coefficient, it was found that PBD does not affect the frequency of complications from pancreatojejunostomy and the development of infectious complications; the absence of cholangiostomy significantly leads to an increase in the frequency of hepaticojejunostomy failure.

The incidence of malignant liver tumors is steadily increasing. Most patients are considered inoperable at the time of detection of a malignant liver lesion. In general, unsatisfactory liver function, comorbidities, bilobar lesion, extrahepatic metastasis allow performing radical treatment in not more than 20 % of cases. Thus, the majority of patients are indicated for other types of treatment, including endovascular locoregional techniques. Taking into account the implementation of the federal program for state support of import substitution in Russia, the creation and production of competitive products in the field of medicine, including for endovascular surgery, becomes relevant. The aim of this article was to study the properties, tolerability and safety of domestically produced saturable microspheres and evaluate the immediate results of transarterial chemoembolization in the treatment of inoperable patients with primary and metastatic liver cancer. Within the framework of the State Scientific Program, clinical studies on the use of saturable microspheres produced in Russia were conducted. The results of treatment of 32 patients who underwent transarterial chemoembolization (TACE) with the use of domestic microspheres “Sphere-Spectrum” at the N.N. Blokhin Research Institute of Oncology from January 2020 to October 2022 were analyzed. Of these, TACE was performed in 24 patients diagnosed with HCC, 5 patients with liver metastases of neuroendocrine tumors, and 3 patients with melanoma metastases. TACE was performed using microspheres with sizes 35–40 in dry (210–240 μm in saturated) 50–60 μm in dry (300–360 μm in saturated), 25 mg or 50 mg in one vial. A total of 40 endovascular procedures were performed in all 32 patients with malignant liver tumor lesions. In 11 of them (34.3 %) a single TACE session was sufficient to achieve an objective response. Partial response was observed in 21 (65.7 %) patients, including those with bilobar metastatic liver lesion. All patients tolerated treatment satisfactorily, the desired therapeutic effect was achieved in 26 (81.2 %) cases (taking into account repeated interventions). One patient (3.1 %) diagnosed with HCC had a complication in the form of liver abscess formation.

Purpose: To review the clinical case of deep infiltrative endometriosis in the patient with suspicious of colorectal cancer.
Material and methods: Patient 47 years old with complaints of pain in the right hypogastrium for several weeks. Anamnesis of laparoscopic surgery for infertility, repeated removal of mammary fibroadenomas. At the initial examination, there is a suspicion of a primary tumor in the rectum with metastatic lesions in the liver, pancreas and peritoneum according to the results of ultrasound diagnosis. Contrast enhanced MRI of the abdominal cavity and pelvic, colonoscopy, lung radiography and PET/CT were performed for the purpose of detailed differential diagnosis of the identified lesions.
Conclusion: The multimodal approach in the differentiation of deep infiltrative endometriosis and malignant neoplasms using various methods of radiation diagnosis allows to assess the spread of the pathological process and determine the tactics of treatment of the patient in the shortest time.