Clinical and treatment characteristics of secondary bladder malignancies following low dose rate brachytherapy for prostate cancer

Chih Peng Chin; William H Smith; Jamie Cesaretti; Mitchell Terk; Evan B Garden; Joseph Sewell Araya; Michael A Palese; Richard G Stock; Michael Buckstein

doi:10.1016/j.urolonc.2022.12.007

Clinical and treatment characteristics of secondary bladder malignancies following low dose rate brachytherapy for prostate cancer

Urol Oncol. 2023 Jun;41(6):296.e9-296.e16. doi: 10.1016/j.urolonc.2022.12.007. Epub 2023 Jan 2.

Authors

Chih Peng Chin¹, William H Smith², Jamie Cesaretti³, Mitchell Terk³, Evan B Garden¹, Joseph Sewell Araya¹, Michael A Palese¹, Richard G Stock², Michael Buckstein⁴

Affiliations

¹ Department of Urology, Icahn School of Medicine at Mount Sinai, New York, NY.
² Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, NY.
³ Terk Oncology, Division of Florida Physician Specialists, Jacksonville, Florida.
⁴ Department of Radiation Oncology, Icahn School of Medicine at Mount Sinai, New York, NY. Electronic address: Michael.buckstein@mountsinai.org.

PMID: 36588020
DOI: 10.1016/j.urolonc.2022.12.007

Abstract

Purpose/objectives: To characterize the clinical course and prognosis of bladder malignancies associated with prior prostate brachytherapy SUBJECTS/PATIENTS AND METHODS: We queried our institutional database for patients with bladder cancer (BC) diagnosed between January 2005 and April 2019 who had previously undergone low dose rate (LDR) prostate brachytherapy. Patients diagnosed with BC at least 1 year following LDR prostate brachytherapy with or without external beam radiation therapy were included. Clinical and disease-specific characteristics were abstracted from chart review and survival outcomes were estimated using Kaplan-Meier estimates. We compared the pathologic characteristics and prognosis of secondary BCs in our study cohort to those of BCs diagnosed after prostate cancer managed without radiation reported by the Surveillance, Epidemiology, and End Results (SEER) populational database from 2005 to 2018.

Results: Three hundred seventy-five patients were identified with combined diagnosis of prostate cancer and BC, 51 of whom met inclusion criteria in the study cohort. Median times from brachytherapy to BC diagnosis for the study and SEER cohort were 9.5 ± 4.5 and 6.3 ± 4.1 years, respectively. Compared to the SEER cohort, significantly greater proportion of BC from the study cohort presented with high-grade (study: 78.4%, SEER: 52.3%, P = 0.0008) and with MIBC (Study BC 35.3%, SEER BC: 17.5%, P = 0.0009). The study and the SEER cohort had similar 5-year overall survival (study: 67.9%, SEER: 58.0%, P = 0.1099), and 5-year cancer-specific survival (study: 81.0%, SEER: 82.8%, P = 0.5559). The 5-year progression-free survival for the study cohort was 43.7% (95% CI: 28.8-57.7).

Conclusion: Compared to bladder cancers following prostate cancer managed without radiation, bladder malignancies following prostate LDR brachytherapy present with higher grade and are more likely to be muscle invasive. Despite the aggressive presenting features of postprostate brachytherapy BC, there were no differences in overall and cancer-specific survival between the groups.

Keywords: Bladder cancer; Brachytherapy; Prostate cancer; Radiation therapy.

MeSH terms

Brachytherapy* / adverse effects
Brachytherapy* / methods
Humans
Male
Neoplasms, Second Primary* / etiology
Prognosis
Prostatic Neoplasms* / pathology
Urinary Bladder / pathology
Urinary Bladder Neoplasms* / epidemiology