3367 - Acute Toxicity and Patient Reported Urinary Quality of Life of Prostate Radiotherapy Following Holmium Laser Enucleation (HoLEP)

12:45pm - 02:00pm PT

Hall F

Screen: 28

POSTER

Presenter(s)

Trevor Wilson, MD, BS - UW Health Radiation Oncology, Madison, WI

T. Wilson¹, M. Taychert², G. Cooley¹, J. M. Floberg³, D. Gralnek², M. D. Grimes², M. Knoedler², C. Manakas², H. Menon¹, and R. Hutten⁴; ¹Department of Human Oncology, University of Wisconsin Hospitals and Clinics, Madison, WI, ²Department of Urology, University of Wisconsin School of Medicine and Public Health, Madison, WI, ³Department of Human Oncology, University of Wisconsin-Madison, Madison, WI, ⁴University of Wisconsin School of Medicine and Public Health, Department of Human Oncology, Madison, WI

Purpose/Objective(s):

Patients who undergo holmium laser enucleation of the prostate (HoLEP) for treatment of lower urinary tract obstructive symptoms may be incidentally diagnosed with prostate cancer. Optimal management of this population is not well defined. However, patients with high grade disease or disease progression (e.g. rising PSA, increased Gleason score on a subsequent biopsy) may be recommended definitive treatment with external beam radiotherapy (EBRT). There have been few reports of toxicity and outcomes of EBRT in patients who have previously undergone HoLEP.

Materials/Methods:

Patients from our institution who previously underwent HoLEP with subsequent EBRT for prostate cancer were identified. Patient information was retrospectively collected and recorded including demographics, PSA, pathology, disease characteristics, treatment characteristics, and acute toxicity data. Urinary quality of life (QOL) scores were collected from multiple time points including pre-HoLEP, post-HoLEP, and post-EBRT.

Results:

Thirty-six patients underwent HoLEP with subsequent EBRT for prostate cancer at a single institution from 2020-2024. Average age at the time of HoLEP was 74.4 years with an average time between HoLEP and radiation of 1.11 years. 47% (17) of patients were Foley catheter-dependent at time of HoLEP. Average IPSS QOL score was 3.8 (1-6) prior to HoLEP and 2.3 (0-5) post-HoLEP. Among patients with available data, median PSA was 6.4 ng/mL (IQR 2.7-9.6 ng/mL) prior to HoLEP and 3.1 ng/mL (IQR 1.3-5.8 ng/mL) prior to EBRT. Pathology results from HoLEP included 21.9% (7) with ISUP grade group (GG) 1 disease, 37.5% (12) GG2, 9.4% (3) GG3, 12.5% (4) GG 4, and 18.8% (6) GG5. Among 25 patients with subsequent prostate biopsy, 56% (14) had high grade disease identified. 75% (27) of patients received moderately hypofractionated radiation with the remainder (9) receiving conventional fractionation. 94.4% (34) of patients received concurrent androgen deprivation therapy. During EBRT, there was an incidence of 2.7% (1) CTCAE grade 3 acute toxicity, 36.1% (13) grade 2, 33.3% (12) grade 1, and 27.8% (10) grade 0. There was no grade 4 or higher acute toxicity. Average IPSS QOL score was 2.23 (0-6) post-EBRT. 15 patients had multiple QOL scores available post-EBRT. With a median follow up time of 17.5 months from completion of EBRT, 93% (14) reported stable or improved urinary QOL (average difference in urinary QOL = -0.67) across post-EBRT follow up visits.

Conclusion:

Patients who underwent EBRT for treatment of prostate cancer after prior HoLEP were at low risk for high-grade acute toxicity or worsening quality of life. Optimal dose/fractionation and timing of post-HoLEP EBRT for definitive treatment warrants further investigation.