Use of bipolar energy for transurethral resection of bladder tumors: pathologic considerations

BACKGROUND AND PURPOSE: Bipolar electrocautery has recently been introduced as a modality for transurethral resection of bladder tumors (TURBT). The primary benefits of bipolar TURBT stem from the use of saline irrigant rather than glycine or water. TURBT should be conducted in a fashion such that the resected tissue can be used for proper grading and staging, so excessive cauterization of the tissue should be avoided. In this study, we compared the pathologic characteristics of bladder tumor specimens resected with bipolar versus standard monopolar energy to determine specimen quality. PATIENTS AND METHODS: Bipolar TURBT (Gyrus Medical Inc., Maple Grove, MN) was performed in 11 patients. Pathologic specimens were compared with the specimens from 11 patients who had previously undergone standard monopolar TURBT. Resected tissue was examined by a pathologist who recorded tumor size, grade, location, presence of muscularis propria, presence of muscle invasion, and final diagnosis. The pathologist also determined the degree of cautery artifact in each specimen. The pathologist was blinded to the form of electrocautery used and the clinical diagnosis. RESULTS: Transurethral resection with bipolar electrocautery was carried out without difficulty or complication in all cases. Similarly, there were no complications in resection by standard monopolar electrocautery. The bladder tumor chips obtained with bipolar TURBT were smaller because of the smaller size of the bipolar loop. However, this did not interfere with the pathologic assessment. There were no significant pathologic differences between specimens according to the type of cautery used. A large degree of cautery artifact was noted in the tissue of larger tumors resected using both monopolar and bipolar electrocautery. However, the incidence and degree of cautery artifact were similar in the two groups. No trends between tumor location and degree of cautery effect were noted. The pathologist had no difficulty reaching a full and proper diagnosis in all cases involving either form of electrocautery. CONCLUSIONS: Bipolar electrocautery is well suited for TURBT. Bladder tissue obtained from bipolar TURBT is of the same histologic quality as that obtained from standard monopolar TURBT and provides the urologist with a reliable and complete diagnosis.