Radiation therapy with curative intention in men with de novo metastatic prostate carcinoma: shoot'em all!

BACKGROUND: About 5% of prostate cancer cases are metastatic at diagnoses. Radiotherapy of both primary tumor and secondary lesions can be, in addition to systemic treatments, a radical alternative for selected patients. MATERIALS AND METHODS: Patients with de novo prostate carcinoma with bone or lymph node metastases were retrospectively reviewed. All patients received moderate hypofractionated IMRT/VMAT up to 63 Gy in 21 daily fractions of 3 Gy to prostate and metastases with neoadjuvant and concurrent androgen deprivation therapy (ADT). According to known advances some patients also received abiraterone, enzalutamide, or docetaxel. RESULTS: Between 2015-2020, we attended 26 prostate cancer patients (median age 69.5 years, range 52-84) with simultaneous oligometastases [mean 2.1 metastases, median 1.5 metastases (range 1-6)]. Eighteen patients (69%) presented lymph node metastases, 4 (15.5%) bone metastases and 4 (15.5%) both lymph node and bone metastases. With a median follow-up of 15.5 months (range 3-65 months), 16 patients (62%) are alive and tumor free while 10 (38%) are alive with tumor. Four patients (17%) developed tumor progression, out of irradiated area in all cases, with a median time to progression of 43.5 months (range 27-56 months). Actuarial progression-free survival (PFS) rates at 12 and 24 months were 94.1% and 84.7%, respectively. No grade > 2 acute or late complications were recorded. CONCLUSIONS: Simultaneous directed radical hypofractionated radiation therapy for prostate and metastases is feasible, well tolerated and achieves an acceptable PFS rate. However, further studies with longer follow-up are necessary to definitively address these observations.