External Beam Radiation Therapy - Target Volume

University Health Network, Toronto27 enrolled

Overview

Delivery of conformal radiation therapy following radical prostatectomy is limited by the inability to define the clinical target volume (CTV). This stems from a poor understanding of patterns of local recurrence and limitations of standard imaging techniques.Magnetic Resonance Imaging (MRI) is a promising modality for imaging the prostatic bed following radical prostatectomy. MRI provides more detailed postoperative anatomy to guide CTV delineation, the ability to document local recurrence patterns, and a method to assess intrafraction prostatic bed motion and deformity to define appropriate planning target volume margins. The aim of this pilot study is to develop a technique for external beam radiation therapy (EBRT) following radical prostatectomy based on MRI-delineation of the CTV. Twenty patients will be enrolled in this pilot, development phase.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

Conditions

Prostatic Neoplasms

Interventions

Eligibility

Sex: MALEMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients following radical prostatectomy for prostate adenocarcinoma with one or more of the following adverse features: pT2 + positive surgical margins ) pT3 ) PSA ≤ 2ng/ml Persistently elevated PSA at 3 months ) * Patients with initially undetectable PSA following prostatectomy for prostate adenocarcinoma with subsequent PSA relapse * Patients being planned for radiation therapy * No evidence of distant metastases * Age ≥ 18 years * ECOG performance status 0 or 1 * Informed consent Exclusion Criteria: * Contraindications to MRI Patients weighing \>136 kgs (weight limit for the scanner tables) Patients with pacemakers, cerebral aneurysm clips, shrapnel injury or implantable electronic devices not compatible with MRI. * Severe claustrophobia * Inflammatory bowel disease or collagen vascular disease * Previous colorectal surgery * Previous pelvic radiotherapy

Outcomes

Primary Outcomes

To develop a technique for MRI-delineation of the clinical target volume (CTV) for EBRT following radical prostatectomy