PSMA-PET Guided Hypofractionated Salvage Prostate Bed Radiotherapy

About This Trial

This study is testing whether a shorter, four-week course of radiation therapy works better at keeping cancer away than the standard seven-week treatment.
It is for men who had their prostate surgically removed, but whose blood tests now show early signs that the cancer may be returning without spreading to other parts of the body.
If you participate, you will be randomly assigned to receive either the standard seven weeks of daily radiation or the newer four-week schedule.
Before joining, you will need a specialized scan to confirm the cancer has not spread, and you cannot take part if you have previously received pelvic radiation or have double metal hip replacements.

After radical prostatectomy approximately 15-40% of men develop a biochemical recurrence (BR) within 5 years.
The standard treatment of post-prostatectomy BR is salvage external beam radiation therapy (sEBRT). sEBRT can provide long-term disease control; with 5 year biochemical progression-free survival (bPFS) up to 60% and with most treatment failures in the first 2 years after sEBRT.
The main goal of this project is to investigate whether the oncologic outcome in patients with post-prostatectomy recurrent PCa can be improved, by increasing the biological effective radiation dose using a hypofractionated schedule of 20 x 3 = 60 Gy.
The study is designed as a prospective open phase III randomized multicenter trial.
All patients with biochemical recurrence with a PSA 0.1 ng/mL or three consecutive rises will be included.
All eligible patients will be randomized to one of the following two treatment arms: Arm 1 = Conventional sEBRT to apply a total dose of 70 Gy in 35 daily fractions of 2 Gy during 7 weeks.
Arm 2 = Hypofractionated sEBRT to apply a total dose of 60 Gy in 20 fractions of 3 Gy during 4 weeks.
The primary endpoint will be the 5-year progression-free survival (PFS) after treatment.

Age Range: 18 - 80 years
Gender: Male
Who This Trial is For: This study is testing whether a shorter, four-week course of radiation therapy works better at keeping cancer away than the standard seven-week treatment.

Full Eligibility Criteria

Inclusion Criteria

Patients with prostate adenocarcinoma treated with radical prostatectomy;
Tumour stage pT2-4, R0-1, pN0, or cN0, cNx according to the UICC TNM 2009, only with Gleason score available;
No lymph node or distant metastases. A recent PSMA-PET scan ( 0.1 ng/mL or 3 consecutive rises. The first value must be measured at least 6 weeks after radical prostatectomy;
PSA at inclusion < 1.0 ng/mL;
WHO performance status 0-2 at inclusion;
Age at inclusion between 18 and 80 years;
Written (signed and dated) informed consent prior to registration.

Exclusion Criteria

Prior pelvic irradiation, (chemo)hormonal therapy or orchiectomy;
Previous or concurrent active invasive cancers other than superficial non-melanoma skin cancers;
Patients with positive nodes or with distant metastases based on the surgical specimen of lymphadenectomy or the following minimum diagnostic workup: PSMA-PET/CT scan, 60 days prior to registration;
Double-sided metallic hip prosthesis;
Inability or unwillingness to understand the information on trial-related topics, to give informed consent or to fill out QoL questionnaires.