Focal Laser Ablation of Prostate Cancer: Phase I Clinical Trial

Shyam Natarajan; Steven Raman; Alan M Priester; James Garritano; Daniel J A Margolis; Patricia Lieu; Maria L Macairan; Jiaoti Huang; Warren Grundfest; Leonard S Marks

doi:10.1016/j.juro.2015.12.083

Focal Laser Ablation of Prostate Cancer: Phase I Clinical Trial

J Urol. 2016 Jul;196(1):68-75. doi: 10.1016/j.juro.2015.12.083. Epub 2015 Dec 31.

Authors

Affiliations

¹ Department of Urology, University of California, Los Angeles, Los Angeles, California; Department of Bioengineering, University of California, Los Angeles, Los Angeles, California; Center for Advanced Surgical and Interventional Technology, University of California, Los Angeles, Los Angeles, California.
² Department of Radiology, University of California, Los Angeles, Los Angeles, California.
³ Department of Bioengineering, University of California, Los Angeles, Los Angeles, California; Center for Advanced Surgical and Interventional Technology, University of California, Los Angeles, Los Angeles, California.
⁴ Department of Urology, University of California, Los Angeles, Los Angeles, California.
⁵ Department of Pathology, University of California, Los Angeles, Los Angeles, California.
⁶ Department of Urology, University of California, Los Angeles, Los Angeles, California; Center for Advanced Surgical and Interventional Technology, University of California, Los Angeles, Los Angeles, California. Electronic address: [email protected].

PMID: 26748164
DOI: 10.1016/j.juro.2015.12.083

Abstract

Purpose: Focal laser ablation is an investigational technique to treat prostate cancer in a region confined manner via coagulative necrosis. This phase I trial primarily examines the safety of transrectal magnetic resonance imaging guided (in-bore) focal laser ablation in men with intermediate risk prostate cancer. An exploratory end point is cancer control after 6 months.

Materials and methods: In an institutional review board approved trial we studied focal laser ablation in 8 men with intermediate risk prostate cancer diagnosed using magnetic resonance-ultrasound fusion. Focal laser ablation was performed by inserting a cylindrically diffusing, water cooled laser fiber into magnetic resonance visible regions of interest, followed by interstitial heating at 10 to 15 W for up to 3 minutes. Secondary safety monitors (thermal probes) were inserted to assess the accuracy of magnetic resonance thermometry. Comprehensive magnetic resonance-ultrasound fusion biopsy was performed after 6 months. Adverse events and health related quality of life questionnaires were recorded.

Results: Focal laser ablation was successfully performed in all 8 subjects. No grade 3 or greater adverse events occurred and no changes in International Prostate Symptom Score or International Index of Erectile Function 5 were observed. Ablation zones, as measured by posttreatment magnetic resonance imaging, had a median volume of 3 cc or 7.7% of prostate volume. Prostate specific antigen decreased in 7 men (p <0.01). At followup magnetic resonance-ultrasound fusion biopsy cancer was not detected in the ablation zone in 5 men but was present outside the treatment margin in 6 men.

Conclusions: Focal laser ablation of the prostate is feasible and safe in men with intermediate risk prostate cancer without serious adverse events or changes in urinary or sexual function at 6 months. Comprehensive biopsy followup indicates that larger treatment margins than previously thought necessary may be required for complete tumor ablation.

Keywords: ablation techniques; laser therapy; multimodal imaging; prostatic neoplasms.

Publication types

Clinical Trial, Phase I
Research Support, Non-U.S. Gov't

MeSH terms

Aged
Feasibility Studies
Follow-Up Studies
Humans
Laser Therapy / methods*
Magnetic Resonance Imaging, Interventional*
Male
Middle Aged
Prostatectomy / methods*
Prostatic Neoplasms / diagnostic imaging
Prostatic Neoplasms / surgery*
Treatment Outcome

Grants and funding

P50 CA092131/CA/NCI NIH HHS/United States