Purpose. To analyze the literature data on the use of CT perfusion in kidney diseases and to assess the future prospects of using the technique in clinical practice. Materials and methods. In electronic databases (PubMed, E-library, Web of Science, Google Scholar), a search was conducted for published studies evaluating the possibilities of using CT perfusion in both neoplastic and non-neoplastic kidney diseases. The article analyzes the results of 40 most relevant works of Russian and foreign researchers devoted to this topic. Results. According to the analysis of the data obtained, perfusion CT is an effective diagnostic tool in oncology: the technique allows noninvasively assessing the nature of the tumour, including differentiating benign nodes (fat-poor angiomyolipoma and oncocytoma) from renal cell carcinoma; to establish the histological variant of renal cell carcinoma and Fuhrman grade, to characterize the effectiveness of ablative techniques and systemic treatment of renal cell carcinoma. Based on the correlation of CT kidney perfusion data and the results of various methods for determining organ function, the possibility of using perfusion CT as one of the prognostic factors for determining the tactics of treatment of patients with obstructive uropathies, aortomesenteric compression, and also shows the potential of using the technique in transplantology both in patients after surgery and during the examination of donors. Conclusions. Despite the fact that the role of CT kidney perfusion in various fields of urology and nephrology has been sufficiently studied, some important aspects of the likely application of this technique remain underestimated. Taking into account the high incidence rates and a significant percentage of localized forms of tumors, the study of the role of CT perfusion in planning and evaluating the results of nephron-sparing treatment of renal cell carcinoma may open up new prospects in optimizing surgical tactics.

Introduction. Survival rates and treatment algorithms for patients with bladder cancer (BC) depend on the depth of tumor invasion, in particular on the presence of the bladder muscle layer invasion and extraorganic spread. To assess the depth of bladder invasion, the VI-RADS system was developed in 2018, which is based on multiparametric MRI (mpMRI). According to published studies on the VI-RADS effectiveness, there is a high diagnostic accuracy for identifying formations with probable invasion into the muscle layer. The data on BC extraorganic spread are limited and the issue of assessing the sensitivity and specificity of this system requires further study. Aim of the study. To evaluate the diagnostic performance of mpMRI using the VI-RADS system in detecting muscle invasion and BC extraorganic growth. Materials and methods. A prospective study was conducted in the clinics of the National Medical Research Radiological Centre and included 75 patients aged 19 to 85 years, of which 39 (52%) had been newly diagnosed with BC, 36 (48%) had a relapse or continuous tumor growth. All patients underwent pelvic organs mpMRI on a tomograph with a magnetic field induction of 1.5T, followed by transurethral resection (TUR), TUR-biopsy of the bladder or cystectomy no later than 6 weeks after scanning.. The description of the bladder tumor included its measurements, localization and VI-RADS scale assessment. The data obtained by mpMRI were compared with the results of the morphological study using statistical analysis. Results. According to the results of the study, the overall VI-RADS scale sensitivity for categories above 3 (the presence of muscle invasion is equivocal) was 95.15% [90.11%; 99.95%], above 4 (muscle invasion is likely) – 92.59% [82.11%; 97.94%], specificity was determined at the level of 47.62% [25.71%; 70.22%] and 80.95% [58.09%; 94.55%] respectively. When assessing extraorganic spread in 30 patients, the sensitivity was 83.33% [62.62%; 95.26%], specificity – 83.33% [35.88%; 99.58%]. The accuracy and positive predictive value also had high levels from 80 to 95%, in contrast to the negative predictive value (55.56%). Conclusion. The scale for BC invasion depth assessing VI-RADS is characterized by high rates of sensitivity, specificity and accuracy, in particular when used in determining extraorganic spread.

А.Б. Гольбиц, Е.В. Крянева, Н.А. Рубцова, Б.Я. Алексеев , А.Д. Каприн 3 Московский научно-исследовательский онкологический институт им. П.А. Герцена – филиал ФГБУ «Национальный медицинский исследовательский центр радиологии» Минздрава России; Россия, 125284 Москва, 2-й Боткинский проезд, 3; Медицинский институт непрерывного образования ФГБОУ ВО «Московский государственный университет пищевых производств»; Россия, 125080 Москва, Волоколамское шоссе, 11; Медицинский институт ФГАОУ ВО «Российский университет дружбы народов»; Россия, 117198 Москва, ул. МиклухоМаклая, 6

Introduction. Currently, CT and MRI do not reliably differentiate oncocytoma, angiomyolipoma with minimal fat and renal cell carcinoma, and therefore most patients with localized solid renal tumors undergo surgical treatment. Identification of differential signs of benign formations according to imaging methods would make it possible to change the therapeutic tactics in more than a third of cases in patients with newly diagnosed small renal masses (less than 4 cm). Purpose. The aim of the study was to evaluate the diagnostic efficacy of diffusion-weighted MRI (DWI) in the differential diagnosis of solid renal masses. Materials and methods. А prospective study, which included 90 patients aged 34 to 79 years with primary solid renal masses who were examined and treated at the Hertsen Moscow Oncology Research Institute – Branch of the National Medical Research Radiological Centre of the Ministry of Health of the Russian Federation was conducted in the period from February 2019 to October 2021. Before surgery, all patients underwent MRI of the retroperitoneal organs using DWI with b-factors of 0–800 s/mm2 and 0–1000 s/mm2. The diffusion coefficient was quantified on two ADC maps for renal masses of various histological types and the obtained values were compared with each other. Results. According to the results of the statistical analysis, the values of the diffusion coefficient for benign tumors were significantly higher than for RCC (p < 0.05). There was no statistically significant difference between clear cell, chromophobe and papillary types of RCC in terms of diffusion coefficient both at b-factors of 0–800 s/mm2 and at 0–1000 s/mm2. Conclusion. Using DWI we can suggest a benign genesis of a solid renal mass. Differential signs for RCC of various histological types according to diffusion-weighted images were not identified.

The classification of cystic renal masses according to computed tomography data, which allows to stratify them depending on the risk of malignancy, was created by M.A. Bosniak in 1986 and modified in 1994. Various groups of researchers have carried out meta-analysis based on the results of applying the proposed classification during the time that has passed since the publication of the last version. Taking into account the information received, which revealed a number of limitations and disadvantages of the previously used method for systematizing renal cystic masses, as well as in connection with the development of medical imaging methods, updated diagnostic algorithms were formulated, which served as the basis for the Bosniak 2019 classification. It is expected that the use of Bosniak 2019 will optimize stratification renal lesions of the cystic structure and reduce the number of removed benign tumors, can be used as a basis for the future research to further improve the classification and its congruence with the requirements of clinical specialists.

In recent decades, due to advances in imaging and improvements in diagnostic algorithms, there has been a tendency to increase the frequency of detection of small renal masses for which nephron-sparing surgery is possible. To predict the potential complexity of partial nephrectomy and to reduce the degree of subjectivity in choosing the volume and method of surgical procedure, different groups of researchers proposed a significant number of concepts for evaluating renal tumours. The R.E.N.A.L. nephrometry score is one of the first but remains relevant and is based on a set of anatomical characteristics. This score allows to classify renal neoplasms in a structured and standardized way. This article presents a method for evaluating the parameters of R.E.N.A.L. nephrometry score, as well as a brief literature review of its prognostic significance.