Evaluatoion of intraoperative histology during nerve-sparing radical prostatectomy

Background. Currently, for patients with localized PC, intact erectile function, and low risk of extracapsular extension radical prostatectomy (RP) with nerve-sparing (NS) technique is indicated. The proven method of intraoperative control for the presence of positive surgical margin is the study of fresh frozen sections.

Aim. To evaluate the method of intraoperative histological examination (cito-histology) in NS RP.

Materials and methods. A prospective clinical study was conducted to examine fresh frozen sections in laparoscopic NS RP. Between February of 2021 and May of 2022, 90 patients diagnosed with prostate cancer underwent laparoscopic NS RP performed by the same surgeon. The patients were divided into 2 groups: group A (n = 40) included patients who underwent laparoscopic NS RP and intraoperative histology; group B (control group) (n = 50) included patients who underwent standard laparoscopic NS RP. Rapid histological and final histological examinations of all removed samples were carried out at the City Clinical Hospital No. 1 named after N.I. Pirogov by one pathologist. The presence of tumor tissue in a stained resection margin was considered positive surgical margin.

Results. Oncological processes in macrosamples obtained by intraoperative histology were observed in 32 (80 %) patients, of which primary positive surgical margin was found in 9 (22.5 %) patients. Conversion of (cito) positive surgical margin status into final negative surgical margin was observed in 4 (10 %) patients. Conversion of the surgical margin status of (cito) negative to positive was observed in 1 (2.5 %) patient due to the targeted examination of the area of interest, and not the entire surface of the prostate. Overall 2-year survival in groups A and B was 100 % and 96 %, respectively; cancer-specific 2-year survival was 100 % and 100 %, respectively. Depending on the pathological group, recurrence-free 2-year survival was: group A (pT2) – 90 %; group B (pT2) – 92 %, group A (pT3) – 91.3 %; group B (pT3) – 77.3 %.

Conclusion. The proposed method of intraoperative histological examination allows to determine the presence and location of positive surgical margin, which indicates to the surgeon the necessity of additional tissue removal in the neurovascular bundle area, reduces the technical and economic burden on pathology department compared to other methods of rapid histological examination, and reduces contraindications to performing the NS technique in RP especially in the intermediate-risk group.

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