High Dose Rate Partial Prostate Brachytherapy as Salvage Treatment for Local Failures After Previous External Beam Radiotherapy
Overview
- Phase
- Not Applicable
- Intervention
- HDR partial prostate brachytherapy
- Conditions
- Recurrent Prostate Cancer
- Sponsor
- British Columbia Cancer Agency
- Enrollment
- 30
- Locations
- 1
- Primary Endpoint
- Late adverse gastrointestinal or genitourinary events grade 3 or higher
- Status
- Recruiting
- Last Updated
- 2 months ago
Overview
Brief Summary
A dose-response relationship for radiation in the management of prostate cancer is well established. Local recurrence of prostate cancer after external beam radiotherapy occurs in at least 40% of patients treated because of inability to deliver sufficient dose through external beam techniques. These patients respond well to re-irradiation using brachytherapy with about 50% of selected patients remaining free of recurrence 5 years after salvage. Advanced imaging using multiparametric Magnetic Resonance Imaging (mpMRI) allows identification of the site of recurrence, permitting partial prostate salvage brachytherapy. There is extensive literature on Low Dose Rate salvage brachytherapy but less on High Dose Rate.
Detailed Description
Appropriately selected patients with histologically documented recurrence 3 years or more after initial external beam radiotherapy will undergo mpMRI for identification of the site of recurrence. A planning transrectal ultrasound (TRUS) will be obtained for fusion with the mpMRI and transposition of the target volume (GTV=gross tumor volume). A margin of 4.5 cm will be added to the GTV to create a focal planning target volume (PTV). The margin may be cropped at the interface with critical organs. Two fractions of HDR brachytherapy will be delivered, each from a single implant, 2 weeks apart. Following treatment patients will be monitored for toxicity and quality of life using the Expanded Prostate cancer Index (EPIC) questionnaire as well as the International Prostate Symptom score. Efficacy will be evaluated by monitoring the Prostate Specific Antigen (PSA) and repeat mpMRI at 2 years.
Investigators
Juanita Crook
Professor of Radiation Oncology
British Columbia Cancer Agency
Eligibility Criteria
Inclusion Criteria
- •Age \>45 and Life expectancy \>10 years
- •Previous External Beam Radiotherapy (EBRT) dose up to 78Gray/39 fractions, 81 Gray/45 fractions or 70 Gray/28 fractions or LDR brachytherapy with site of recurrence in an under-dosed or untreated site
- •\> 3 year interval since EBRT or LDR Brachytherapy
- •No late toxicity from prior EBRT ≥ grade 2
- •Rising PSA post EBRT \> nadir + 2 ng/ml but \< 10 ng/ml
- •PSA Doubling time \> 6 months
- •Negative staging with CT scan of the abdomen/pelvis and bone scan (PSMA PET scan can replace CT and bone scan)
- •Able to undergo multiparametric MRI with endorectal coil
- •Radiographic evidence of dominant intraprostatic lesion (DIL) as only area of recurrence (i.e unifocal recurrence) and corresponding to site of original disease
- •Biopsy confirmation of DIL with pathology review by British Columbia Cancer Agency GenitoUrinary pathologist (TB)
Exclusion Criteria
- •Not compliant with criteria above
- •Unable to give informed consent
Arms & Interventions
HDR partial prostate brachytherapy
2 fractions of high dose rate prostate brachytherapy will be delivered to the site of recurrent disease as determined by mp-MRI
Intervention: HDR partial prostate brachytherapy
Outcomes
Primary Outcomes
Late adverse gastrointestinal or genitourinary events grade 3 or higher
Time Frame: 3-60 months
Common Terminology Criteria for Adverse Events (CTCAE V4.0)
Secondary Outcomes
- Late Quality of Life(3-60 months)
- Late lower urinary tract symptoms(3-60 months)
- Acute grade 3 or higher gastrointestinal or genitourinary adverse events(0-3 months)
- Acute Quality of Life changes(0-3 months)
- Acute lower urinary symptoms(0-3 months)
- Biochemical disease free survival(60 months)
- Number of participants with site of recurrence on mpMRI improved from PiRADS 4 or 5 to PiRADS 3 or less.(2 years)