Partial Prostate Salvage High Dose Rate Brachytherapy (SalvageHDR)

British Columbia Cancer Agency

Status

Enrolling

Conditions

Recurrent Prostate Cancer

Treatments

Radiation: HDR partial prostate brachytherapy

Study type

Interventional

Funder types

Other

Identifiers

NCT03246802

H17-01641

Details and patient eligibility

About

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.

Full 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.

Enrollment

30 estimated patients

Sex

Male

Ages

45 to 80 years old

Volunteers

No Healthy Volunteers

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)
Willing to provide informed consent
History and physical examination within 90 days of registration
ECOG performance status 0-1 prior to registration
IPSS < 16, or adequate voiding study (post void residual < 100cc and peak flow rate > 10 cc/second).
No prior trans urethral prostatic resection
Recurrence suitable for implant with HDR brachytherapy as assessed on ultrasound simulation (maximum PTV ideally < 65% of prostate volume)
No history of inflammatory bowel disease or previous rectal surgery
Suitable for procedure under anesthesia, spinal or general
INR <2.5 and platelet count >75 x 109/L
Androgen Deprivation Therapy may be initiated at the discretion of the treating oncologist