Histologic effects of holmium:YAG laser resection versus transurethral resection of the prostate

Holmium laser resection (HoLRP) is an effective surgical alternative to transurethral resection of the prostate (TURP). We investigated whether an adequate histologic diagnosis could be made from HoLRP tissue specimens.

A series of 120 patients were randomized to TURP (N = 59) or HoLRP (N = 61). Each histologic specimen was reviewed by a single pathologist, who was blinded to the treatment. Weight of tissue, histologic diagnosis, and degree of thermal artifact were assessed. Thermal damage was graded as follows: 1 = no significant thermal injury; 2 = <25% of the tissue damaged (minimal); 3 = 25% to 80% of the tissue damaged (moderate); and 4 = >80% of the tissue damaged, with loss of prostatic architecture (extensive).

The mean weight of the TURP and HoLRP specimens was 15.6 g and 9.6 g, respectively. The mean grade of thermal artifact for the TURP group was 1.8 and for the HoLRP group 2.6. Of the HoLRP specimens, 56 (92%) were grade < or = 3. Of the entire series of 120 specimens, 5 contained malignant tissue, all of which were from the TURP group. Four of these specimens were adenocarcinoma of the prostate, whereas the other was a transitional-cell carcinoma. Of the four specimens that contained prostate cancer, two were stage pTla tumors.

Although identifiable prostatic architecture was maintained in the majority of histologic specimens from the HoLRP group, the tissue quality was inferior to that of TURP. There was significantly more vaporization and subsequent tissue loss with HoLRP, and the thermal damage to tissue was greater.