Purpose Rezum is a minimally invasive surgery for benign prostatic hyperplasia. Current guidelines recommend Rezum for prostates < 80 cc, but little data exist describing outcomes in patients with prostates ≥ 80 cc. We compare outcomes after Rezum between men with small < 80 cc (SP) and large ≥ 80 cc prostates (LP). Methods Patients undergoing Rezum between Jan 2017-Feb 2020 were subdivided by prostate volume (< 80, ≥ 80 cc). Outcomes were documented pre-and postoperatively. Descriptive analyses of urodynamics data (Qmax, PVR), symptom scores (AUA-SS, SHIM), disease management (medications, catheterization, retreatments), and clinical outcomes were conducted. Results 36 (17.6%) men had prostates ≥ 80 cc (LP mean prostate size 106.8 cc). LP men had improved Qmax and PVR postoperatively; those with longitudinal follow-up exhibited improved Qmax, PVR, and AUA-SS. After one year, alphablocker usage decreased significantly (LP 94.44-61.11%, p = 0.001, SP 73.96-46.15%, p = 0.001); other medication usage and self-catheterization rates remained unchanged. Compared to SP patients, differences in passing trial void (LP 94.44%, SP 93.45%), postoperative UTI (LP 19.44%, SP 10.12%), ED visits (LP 22.22%, SP 17.86%), readmissions (LP 8.33%, SP 4.76%), and retreatment (LP 8.33%, SP 4.76%) were insignificant. However, mean days to foley removal (LP 9, SP 5.71, p = 0.003) and urosepsis rates (LP 5.56%, SP 0.00%, p = 0.002) differed. Conclusion In select LP patients, Rezum provided short-term symptomatic relief and improved voiding function comparable to SP patients. Postoperatively, though alpha-blocker usage decreased significantly, use of other medications did not change, and nearly two-thirds of patients still needed alpha-blockade. Further efforts should explore the possibility of expanding Rezum's inclusion criteria.
