Partial prostate gland ablation results in similar oncologic and functional outcomes whether or not it targets lesions visible on MRI, investigators reported at the American Society of Clinical Oncology’s 2023 Genitourinary Cancers Symposium in San Francisco, California.
The finding is based on a study that included 115 men treated at Weill Cornell Medicine in New York City from 2017 to 2022 with cryoablation, irreversible electroporation, or high-intensity focused ultrasound for prostate cancer lesions. Of these, 79 men had MRI-visible lesions and 34 had MRI-invisible lesions detected on systematic biopsy outside of the MRI-targeted zone (2 patients were lost to follow-up).
Failure of partial gland ablation occurred in 48.3% of men with surveillance biopsy results, Alec Zhu, MD, of Weill Cornell Medicine reported for his team. The failure rate did not differ significantly between the groups with MRI-visible and MRI-invisible lesions (50.9% vs 42.9%). Median follow-up was 15 months for both groups. The investigators defined failure as persistence or recurrence of Gleason grade group (GGG) 2 or higher disease on surveillance biopsy. For patients with GGG 1 prostate cancer, failure was defined as detection of GGG 1 or higher prostate cancer on surveillance biopsy.
“Partial gland ablation of MRI-invisible prostate cancer has been controversial,” coinvestigator Jim C. Hu MD, MPH, of Weill Cornell Medicine said in an interview. “We found that the treatment failure rate for MRI-invisible lesions is the same as for MRI visible lesions. There is significant distortion of the prostate after treatment to be able to accurately ascribe the failure to the ablation itself or to multifocality of prostate cancer, which is present in three-quarters of patients.
“The challenge is many centers do not perform surveillance prostate biopsy after partial gland ablation,” he continued. “Some just monitor PSA. More evidence on partial gland ablation is needed.”
Rates of 30-day complications did not differ significantly between the MRI-visible and MRI-invisible groups.
The investigators assessed health-related quality of life outcomes using the Expanded Prostate Cancer Index-Clinical Practice (EPIC-CP). Mean total EPIC-CP scores appeared comparable between groups at baseline, 3, 6, and 12 months after partial gland ablation.
Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Zhu A, Gereta S, Stangl-Kremser J, et al. Partial gland ablation outcomes for localized prostate cancer in patients with MRI-visible and MRI-invisible lesions. Presented at: ASCO GU 2023, San Francisco, California, February 16-18. Abstract 368.