[Interpretation of biopsy material after transuretral and laser en bloc resection of non-muscle-invasive bladder cancer]. / Interpretatsiya biopsiinogo materiala posle transuretral'noi i lazernoi rezektsii edinym blokom nemyshechno-invazivnogo raka mochevogo puzyrya.

Bladder cancer is one of the most common onco-urological diseases, ranked second in frequency among all tumors of the urinary system after prostate cancer. At the time of detection of the primary tumor, approximately 75% of patients have no invasion into the muscularis layer (non-muscle-invasive carcinoma), with tumor growth limited to the basal membrane (stage Ta) or submucosal base (stage T1). Removal of the tumor in a «unified block¼ (laser en-bloc resection or L-ERBT), unlike routine transurethral resection, allows to obtain qualitative biopsy material for precise pathomorphological staging of the tumor process. In order to accurately stratify a patient into one or another risk group, verification of the following morphological parameters is required: degree of tumor differentiation and its malignancy, depth of invasion, foci of carcinoma in situ at resection margins, presence or absence of lymphovascular invasion. Identification of tumor variant histology is also recommended. Information on presence or absence of detrusor elements in the specimen is necessary in the morphological report, as this parameter is considered as a criterion of radically performed tumor removal. According to ICCR recommendations (International Collaboration on cancer reporting), it is recommended to use subclassification of T1 stage using all possible criteria: volume and/or depth of invasion (assessed in mm), and/or width of invasion «spot¼ (assessed in mm), and/or involvement of anatomical structure - muscularis mucosae. Full morphological examination of the material obtained during the primary resection of the tumor is an important step in the diagnosis and treatment of bladder cancer, as it allows to stratify the patient into one or another risk group and, accordingly, allows to develop a personalized postoperative management.

[Novel approaches for transurethral en-bloc resection of large bladder tumors].

OBJECTIVE: to develop optimal techniques of en-bloc resection of large non-muscle invasive bladder tumors, determine the proper method of specimen extraction and assess the quality of specimens obtained by different techniques. MATERIALS AND METHODS: A total of 12 patients with primary cT1 bladder cancer underwent transurethral en-bloc resection between January 2018 and March 2019 were enrolled into the study. Tumor size ranged from 3.5 cm to 6.2 cm. For removal and extraction of large bladder tumors using thulium fiber en-bloc laser three different techniques were developed: "swiss cheese technique", "crown and root technique" and "three steps technique" technique". The main pathologic criteria used for assessment of removal technique were tumor grade (G), depth of invasion (T), presence of carcinoma in situ (CIS), variant histology (VH), lymphovascular invasion (LVI), presence of detrusor muscle. Additional criteria were horizontal and vertical resection margin, subclassification of T1-stage and presence of focal necrosis in tumor. RESULTS: Among the techniques developed and tested, the best quality of specimens for morphological evaluation was obtained using the combined "crown and root technique". First step is electroresection of the exophytic part of the tumor into pieces, and the next step is en-bloc laser resection (using thulium fiber or holmium laser) of the tumor base. Overall, the quality of all specimens obtained using three techniques met the current requirements of pathologic study. SUMMARY: En-bloc resection techniques of large bladder tumors allow obtaining specimen suitable for proper morphological evaluation and correct tumor staging. Further studies are required to evaluate the impact of these techniques on long-term results of treatment options.

[En-bloc laser resection of the urinary bladder tumor].

Currently, transurethral resection of a bladder tumor (TUR) is the gold standart treatment for non-muscle invasive bladder cancer (NMIBC). Standard TUR for a bladder wall tumor has a high recurrence rate, which is caused mainly by malignant cell implantation during the surgery. Besides, specimens obtained with conventional TUR are insufficient for accurate pathological staging. The non-conformity of the standard TUR with the established oncological principle of dissecting through normal tissue prompted a search for the optimal surgical modality. En-bloc resection of the bladder wall tumor has been proposed as an alternative method for surgical management of NMIBC. This technique involves the resection of bladder tumor through the underlying muscle layer as a single piece thus providing high quality material for subsequent morphological study and reducing the risk of metastasizing by implantation of malignant cells. This paper presents an analysis of relevant research literature published in the last twenty years, describes all currently existing techniques of the bladder tumor resection using a variety of energy sources, including laser.