Phase I study of dose escalation to dominant intraprostatic lesions using high-dose-rate brachytherapy

Christopher H. Chapman; Steve E. Braunstein; Jean Pouliot; Susan M. Noworolski; Vivian Weinberg; Adam Cunha; John Kurhanewicz; Alexander R. Gottschalk; Mack Roach III; I-Chow Hsu

doi:10.5114/jcb.2018.76881

eISSN: 2081-2841
ISSN: 1689-832X

Journal of Contemporary Brachytherapy

Current Issue Archive Supplements Articles in Press Journal Information Aims and Scope Editorial Office Editorial Board Register as Author Register as Reviewer Instructions for Authors Abstracting and indexing Subscription Advertising Information Links

Editorial System

Submit your Manuscript

3/2018
vol. 10

Send email

Copy url:

abstract:

Original paper

Phase I study of dose escalation to dominant intraprostatic lesions using high-dose-rate brachytherapy

Christopher H. Chapman

,

Steve E. Braunstein

,

Jean Pouliot

,

Susan M. Noworolski

,

Vivian Weinberg

,

Adam Cunha

,

John Kurhanewicz

,

Alexander R. Gottschalk

,

Mack Roach III

,

I-Chow Hsu

J Contemp Brachytherapy 2018; 10, 3: 193–201

DOI: https://doi.org/10.5114/jcb.2018.76881

Online publish date: 2018/06/29

View full text Get citation

Purpose
Radiation dose escalation for prostate cancer improves biochemical control but is limited by toxicity. Magnetic resonance spectroscopic imaging (MRSI) can define dominant intraprostatic lesions (DIL). This phase I study evaluated dose escalation to MRSI-defined DIL using high-dose-rate (HDR) brachytherapy.

Material and methods
Enrollment was closed early due to low accrual. Ten patients with prostate cancer (T2a-3b, Gleason 6-9, PSA < 20) underwent pre-treatment MRSI, and eight patients had one to three DIL identified. The eight enrolled patients received external beam radiation therapy to 45 Gy and HDR brachytherapy boost to the prostate of 19 Gy in 2 fractions. MRSI images were registered to planning CT images and DIL dose-escalated up to 150% of prescription dose while maintaining normal tissue constraints. The primary endpoint was genitourinary (GU) toxicity.

Results
The median total DIL volume was 1.31 ml (range, 0.67-6.33 ml). Median DIL boost was 130% of prescription dose (range, 110-150%). Median urethra V120 was 0.15 ml (range, 0-0.4 ml) and median rectum V75 was 0.74 ml (range, 0.1-1.0 ml). Three patients had acute grade 2 GU toxicity, and two patients had late grade 2 GU toxicity. No patients had grade 2 or higher gastrointestinal toxicity, and no grade 3 or higher toxicities were noted. There were no biochemical failures with median follow-up of 4.9 years (range, 2-8.5 years).

Conclusions
Dose escalation to MRSI-defined DIL is feasible. Toxicity was low but incompletely assessed due to limited patients’ enrollment.

keywords:

Phase I study of dose escalation to dominant intraprostatic lesions using high-dose-rate brachytherapy

Christopher H. Chapman , Steve E. Braunstein , Jean Pouliot , Susan M. Noworolski , Vivian Weinberg , Adam Cunha , John Kurhanewicz , Alexander R. Gottschalk , Mack Roach III , I-Chow Hsu

focal, image-guided brachytherapy, intraprostatic, prostate cancer

Christopher H. Chapman

,

Steve E. Braunstein

,

Jean Pouliot

,

Susan M. Noworolski

,

Vivian Weinberg

,

Adam Cunha

,

John Kurhanewicz

,

Alexander R. Gottschalk

,

Mack Roach III

,

I-Chow Hsu