Protons are the relatively heavy charged particles and therefore can be accelerated to any energy, permitting the long distance penetration in the human body practically without loss of the dose-rate. In addition, due to the low side scatter the use of these particles permits obtaining the better dose distribution between the tumor and the surrounding healthy tissues in comparison with the traditional sources of ionizing radiations. The limited clinical study of proton radiotherapy was initiated in early 1950th in USA and shortly afterwards in Sweden, and at the end of 1960th have started in USSR at two physical institutions located in Dubna and Moscow. Later the third institution — in Gatchina, the suburb of Leningrad, started treatment of tumors with the beams of accelerated protons. And to the end of 1980th the USSR has accumulated the largest experience in the world in using proton beams for treatment of patients with malignant and benign tumors as well as blood vessel malformations in brain. During last thirty years proton radiotherapy became widely used method in oncology, especially due to the shift from the use of huge physical installations to the specially designed ‘medical accelerators’ which are installed now in many medical institutions. The number of the treated patients grows to two hundred thousand, and now one of the main tasks is determination of those patients to whom this expensive type of radiotherapy could be the most efficient. This efficiency is evaluated either on the better results of tumor treatments or, which is especially important for proton radiotherapy, on the better sparing of normal tissue damage in comparison with the efficacy of tumor eradiation usual for other sources of radiation.

Every year, about a million electronic devices implanted in the heart are installed worldwide. In the Russian Federation, there are no accurate statistics on pacemakers. Modern pacemakers (pacers) are characterized by their small size, high sensitivity and susceptibility to ionizing radiation (IR), which increases the risk of temporary or irreversible damage to the device. Throughout the world, the number of cancer patients with electronic devices implanted in the heart has increased over the past decade. Despite the development of modern methods of radiation therapy (RT), this method has a certain risk of complications for cancer patients with ECS.

We currently use the 2020 update of the JASTRO/JCS guidelines for RT in patients with cardiac implantable devices to guide management of patients with pacemakers. Similar recommendations have not yet been developed in the Russian Federation, as in many other countries, which makes this problem especially relevant.

This article demonstrates a multidisciplinary team approach to the management and treatment of patients with esophageal squamous cell carcinoma (ESCC) with an implantable pacemaker.

Purpose: A comparative study of the content of lipid peroxidation (LPO) products and the activity of the main antioxidant enzymes in the blood plasma of patients with brain metastases (BM) under various radiotherapeutic treatment options.

Material and methods: The study included 37 patients with BM. Three groups of patients were formed: Control group (12 patients), in which stereotactic radiotherapy with a single focal dose of 6 Gy to a total dose of 30 Gy was performed on the place of the removed metastasis; Main group No. 1 (6 patients) — after a session of preoperative radiosurgery with a dose of 10-15 Gy, the metastatic focus was removed after 24 hours; Main group No. 2 (19 patients) — staged radiosurgery (SRS) was carried out in 3 stages with a dose of 10 Gy with an interval between sessions of 14 days (total dose of 30 Gy). In the blood plasma of 37 patients, the content of malondialdehyde (MDA), diene conjugates (DC), and the activity of superoxide dismutase and catalase were determined by standard spectrophotometric methods. The comparison group included 21 people without cancer (donors). Statistical processing of the results was carried out using the Statistica 10.0 program. using Student’s t-test and nonparametric Mann–Whitney test.

Results: Before treatment, the MDA content was increased in all patients, on average by 83.5 % (p = 0.00025) relative to the donor group; in the majority, DC was also increased (by 60.4 %, p = 0.0498). After removal of the metastatic lesion in patients in the Control and Main group No. 1, the level of LPO products remained elevated. And only in the Main Group No. 2, already before the 3rd session of SRS, a decrease in the level of MDA was observed in patients with a removed primary lesion, as well as normalization of DC in all patients and restoration of the coordinated work of antioxidant enzymes. An increase in MDA content with reduced catalase activity in patients with an unremoved primary lesion at the stages of SRS may reflect the mechanism of tumor cell reduction under the influence of increased production of free radicals during long-term radiation exposure.

Conclusions: The use of SRS, in contrast to other radiotherapy options, helps to normalize the redox status of the blood of patients with metastatic brain lesions. Analysis of the data obtained suggests greater effectiveness of SRS in patients with a removed primary lesion.

Purpose: To compare dosimetric plans obtained in patients with breast cancer (BC) that underwent accelerated partial breast irradiation (APBI) by conformal external beam radiotherapy (EBRT) or interstitial high dose rate brachytherapy (HDRB).

Material and methods: From 2017 to 2022 APBI was performed in 210 patients with stage I–II BC (рТ₁N₀M₀–pT₂N₀M₀). APBI was delivered to the tumor bed: in 99 cases — by EBRT, in another 111 patients — by HDRB. Leſt breast was irradiated in 101 women: in 51 women using HDRB, in 50 patients — by EBRT. Following dosimetric parameters were used for comparison of the dosimetric plans: D_max – maximum dose in the organ at risk; D_med – mean dose in the organ at risk (heart, leſt main coronary artery and its descending branch, ipsilateral lung, breast, skin and subcutaneous tissues).

Results: When the tumor bed was irradiated by HDRB, in comparison with EBRT, D_max for the skin and subcutaneous tissue decreases from 98.4 % to 68.7 %, р < 0.002. The use of HDRB made it possible to reduce the radiation load on the ipsilateral lung: D_max decreased from 71.9 % to 42.7 % , р < 0.002; D_med was 5.5 % for HDRB and 2.9 % for EBRT, р > 0.05. On the contrary EBRT associated with higher dose to the breast D_med breast — 46 % in comparison with HDRB D_med breast — 16.5 % , р < 0.002. Dose to the heart was higher with HDBT D_max heart — 20.2 %, D_med heart was 4.9 % than with EBRT D_max heart — 14.4 %, D_med heart — 0.8 %. Dose to the left coronary artery with HDRB D_max — 6.5 % , D_med — 3.9 % was higher than with EBRT D_max — 3.3 % , D_med — 1.3 % . Dose to the descending branch of the left coronary artery was higher with HDRB D_max — 12.6 % , D_med — 9.3 % than with EBRT D_max — 8.9 % and D_med — 3.4 % . But this differences were non-significant (р > 0.05).

Conclusions. APBI by HDRB associated by significant reduction of the radiation dose to the ipsilateral breast lung, breast, skin and subcutaneous tissues.

Purpose: To demonstrate the capabilities of PET/CT with ¹⁸F-PSMA-1007 in comparison with ¹⁸F-FDG in the diagnostics of metastatic ccRCC.

Material and methods: Ninety-seven patients with metastatic ccRCC were included in the study. Biopsy results of the primary tumor were available in all patients. Metastatic foci were confirmed by biopsy, follow-up and other diagnostic methods. All patients under went PET/CT with ¹⁸F-PSMA-1007 and ¹⁸F FDG.

Results: A total of 1247 metastases were identified in 97 patients: 1002 — PSMA-positive, 245 — PSMA-negative, 694 — FDG-positive, and 553 — FDG-negative. The largest number of foci was found in the lungs (601 in 43 patients), bones (220 in 46 patients), and lymph nodes (166 in 34 patients).

Sixty-two patients had more PSMA-positive foci compared with ¹⁸FDG, 32 had an equal number of foci, and 3 had more foci according to PET/CT with ¹⁸FDG.

The sensitivity and specificity of ¹⁸F-PSMA-1007 in the diagnostics of ccRCC metastases were 80 % and 72 %, positive and negative predictive value were 87 % and 61 %, respectively.

The sensitivity and specificity of ¹⁸F-FDG in the diagnostics of ccRCC metastases were 55 % and 54 %, positive and negative predictive value were 69 % and 41 %, respectively.

The mean SUV_max difference between ¹⁸F-PSMA-1007 and ¹⁸FDG was 5.32, and the mean TBR difference was 5.66. Lung foci demonstrated significantly lower SUV_max and TBR for both RPs compared to other metastases.

Discussion and conclusions. Data analysis demonstrates higher efficiency of ¹⁸F-PSMA-1007 compared to ¹⁸F-FDG in the diagnostics of ccRCC metastases. PET/CT with ¹⁸F-PSMA-1007 revealed a higher number of metastases, SUV_max and TBR in studies with ¹⁸F-PSMA-1007 are on average significantly higher than those with ¹⁸F FDG.

PET/CT with ¹⁸F-PSMA-1007 demonstrates the lowest efficiency in the diagnosis of foci in the lungs up to 1 cm. It is feasible to analyze pulmonary foci and other metastases separately to exclude the influence of a large number of low-active and false-negative foci on statistical parameters.

PET/CT with ¹⁸F-PSMA-1007 can be recommended for use in patients with suspected metastatic ccRCC as an alternative to routine diagnostic methods and PET/CT with ¹⁸F-FDG. The potential of ¹⁸F-PSMA-1007 in assessing the efficacy of systemic therapy requires further investigation.

The first clinical case describes the main ultrasound signs of a foreign body in the form of suture material after surgery on the stomach, the second clinical case presents the ultrasound signs of an installed intraperitoneal port for chemotherapy after extirpation of the uterus and appendages. The article compares the types of intraoperative foreign bodies, the clinical picture, and the main diagnostic methods.

Purpose: The article describes a variety of liver lesions, hyperintensity in the hepatobiliary phase of gadoxetic acid-enhanced MRI and the added value of gadoxetic acid in their differential diagnosis with consideration of its pharmacokinetics.

Material and methods: Gadoxetic acid-enhanced MRI scans of 19 patients with slight hyperintensity lesions in the hepatobiliary phase, were retrospectively assessed, the role of DWI in differential diagnosis of rare types of hepatocellular carcinoma (HCC) and focal nodular hyperplasia (FNH) was evaluated and the statistical analysis was performed.

Results: The combination of evaluated MRI semiotics features — hyperintensity in native, arterial, portal venous and hepatobiliary phases, slight hyperintensity on DWI (b-value 800 and b-value 400 s/mm²), rim enhancement (“capsule”) — enables differentiation of rare types of HCC and HCC with atypical enhancement in patients with FNH.

Conclusion: MRI with hepatobiliary contrast agents in junction with DWI increases the accuracy of identification of liver lesions and allows differentiation of rare types of HCC with atypical enhancement in patients with FNH without morphological verification.

Introduction: The standard treatment for locally advanced oral cavity cancer is surgery with followed by chemoradiotherapy Surgical treatment carries serious external and aesthetic risks and a long period of rehabilitation. On the other hand, standard chemoradiation treatment does not achieve adequate results. Intra-arterial chemotherapy is a promising treatment option. This method allows targeting the tumor to be while minimizing systemic factors and organ preservation, and the quality of life of the patients.

Purpose: To compare the results of treatment of patients with locally advanced oral cancer using induction intra-arterial chemotherapy and surgical treatment at the first step.

Material and methods: 62 patients were treated from 2017 to 2023 with locally advanced oral cancer. 23 patients underwent induction chemotherapy according to the DCF regimen with intra-arterial administration of cisplatin and docetaxel. In the second group, 39 patients underwent combined treatment with surgical treatment at the first step. The primary endpoint of the study was overall and disease-free survival. Secondary — objective response, treatment toxicity and the occurrence of prognostic factors in the intra-arterial chemotherapy group.

Results: The duration of follow-up of patients in the intra-arterial group was 20.37 (CI 13.23–25.87) and in the surgery group 32.6 (CI 17.1–43.6) months. 1-year overall survival (OS) in the intra-arterial group and in the surgical group was 84.1 % and 69.2 % (p = 0.582), relapse-free survival (RFS) — 77.9 % and 62.5 % (p = 0.944). A subgroup analysis revealed an improvement in OS in patients treated with one arterial basin (p = 0.005). 1-year OS aſter induction chemotherapy for complete response, partial response, and stabilization were 90.9, 67.5, and 0 % (p < 0.001), respectively. 1-year RFS for complete response, partial response, and stabilization were 80, 76.2, and 0 % (p < 0.000), respectively.

Conclusions: Intra-arterial chemotherapy has equivalent efficacy in terms of survival in patients with locally advanced tumors, oral cavity conclusion is indicated.

Relevance: Currently, medical liquid radioactive waste (LRW) in radionuclide therapy units (RTU) is sent via special sewerage to storage tanks, where it is kept for radioactive decay. When the established standard for specific radioactivity is reached, the accumulated LRW is discharged into the domestic sewerage system. However, if LRW contains radiopharmaceuticals with several different radionuclides, determining the optimal holding time is a complex task.

Purpose: Analysis of existing and development of new technologies for the removal of LRW with a complex radionuclide composition in RTU units.

Material and methods: The advantages and disadvantages of the existing technology for determining the holding time of liquid radioactive waste in a storage tank based on the results of radiometry of periodically collected samples of liquid radioactive waste are considered. It is shown that it does not meet the requirements for reducing labor intensity and ensuring radiation safety of the RTU unit personnel. Six new technologies for managing liquid radioactive waste removal are proposed, of which a technology based on a single dosimetry of γ‑radiation from a filled tank with subsequent calculation of the holding time to determine the moment of timely discharge of decayed liquid radioactive waste into the domestic sewage system is proposed for practical application.

Results: Using the proposed technology, the optimal moment for discharging the contents of a tank with liquid radioactive waste accumulated in it, which are radiopharmaceuticals excreted from the body of patients labeled with radionuclides ¹³¹I, ¹⁵³Sm, ¹⁷⁷Lu, is determined.

Conclusion: The developed technology for the removal of liquid radioactive waste is characterized by accuracy acceptable for radiation‑hygienic purposes while ensuring simplicity and low labor intensity of its practical application in the RNT departments of domestic medical institutions.

This article is dedicated to such a congenital anomaly of human development as an accessory spleen. In our article we discuss the main causes of its occurrence, indicate the most frequent localizations, discuss the complexity of diagnosis, and demonstrate the modern possibilities of medical imaging in differential diagnosis of this pathology with other neoplasms of the abdominal cavity. Moreover, we present a clinical case of an accessory spleen located in an atypical place — in the liver gates, which is a rare finding. The article is illustrated with original computed tomography, magnetic resonance imaging, and radionuclide studies scans.

In this clinical case we analyzed the need for a correct algorithm for examining patients with liver tumors when making a primary diagnosis, thus it significantly affects the prognosis and course of the disease. We demonstrate capabilities of various diagnostic methods in the differential diagnosis of focal liver lesions. Our clinical case confirms the need for optimal routing schemes for patients to specialized centers that have all necessary resources to perform all types of diagnostic methods, including nuclear medicine diagnosis, as well as the presence of a multidisciplinary team of specialists. The article is illustrated with original images of nuclear medicine studies, CT and MRI images.

A brief review of the literature and our own detailed description of POEMS syndrome according to PET/CT data with ¹⁸F FDG in a 26-year-old patient are provided. A comprehensive examination was carried out and appropriate systemic therapy was prescribed.