LASER EN-BLOC RESECTION OF NON-MUSCLE-INVASIVE BLADDER CANCER: CLINICAL AND MORPHOLOGICAL SPECIFICITIES

Objectives to enhance the morphological diagnostic complex in order to predict postoperative outcomes in a more accurate way and to optimize patients with non-muscular invasive bladder cancer treatment.

Materials and methods. The study included 34 patients from 25 to 71 years old underwent laser en-block resection, the most of them were males – 28. In 9 cases multiple carcinomas (2 or more) were found. Huge tumors (2 cm or more in one dimension) were resected in 6 patients. Results. The major part of tumors removed (n = 22) histologically appeared to be papillary urothelial carcinomas with low grade of malignancy and PUNLMP; in 6 cases G2 was verified, one tumor with high malignancy potention – G3. In 3 patients intramuscular invasion was found (invasive carcinoma T2) excluding them from the study.

Discussion. Laser en-block resection of non-muscle-invasive bladder cancer appears to be the most optimal approach in operative treatment that provides representative histological material. For correct morphological estimate we recommend either to expand the resection zone to 1 cm which allows to remove circular resection margin or to take extra pinch biopsy from tumor crater (vertical margin). In 3 patients from our study positive circular margin was revealed histologically whereas foci of perineural and perivascular invasion were found in one case. A new subgrading of stage T1 depending on intramuscular invasion depth was suggested whereas the main criteria is the muscularis mucosae involvement.

Conclusion. Morphological estimate of circular resection margin provides an ability to predict postoperative outcomes and correct the treatment in one or another way. Subgrading for T1-stage tumors is recommended for following correct postoperative prognosis and possibility of tumor recurrence.

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