Systemic and tumor-directed therapy for oligometastatic prostate cancer: study protocol for a phase II trial for veterans with de novo oligometastatic disease.

The treatment paradigm for metastatic hormone-sensitive prostate cancer (mHSPC) patients is evolving. PET/CT now offers improved sensitivity and accuracy in staging. Recent randomized trial data supports escalated hormone therapy, local primary tumor therapy, and metastasis-directed therapy. The impact of combining such therapies into a multimodal approach is unknown. This Phase II single-arm clinical trial sponsored and funded by Veterans Affairs combines local, metastasis-directed, and systemic therapies to durably render patients free of detectable disease off active therapy.

Patients with newly-diagnosed M1a/b prostate cancer (PSMA PET/CT staging is permitted) and 1-5 radiographically visible metastases (excluding pelvic lymph nodes) are undergoing local treatment with radical prostatectomy, limited duration systemic therapy for a total of six months (leuprolide, abiraterone acetate with prednisone, and apalutamide), metastasis-directed stereotactic body radiotherapy (SBRT), and post-operative fractionated radiotherapy if pT ≥ 3a, N1, or positive margins are present. The primary endpoint is the percent of patients achieving a serum PSA of < 0.05 ng/mL six months after recovery of serum testosterone ≥150 ng/dL. Secondary endpoints include time to biochemical progression, time to radiographic progression, time to initiation of alternative antineoplastic therapy, prostate cancer specific survival, health related quality-of-life, safety and tolerability.

To our knowledge, this is the first trial that tests a comprehensive systemic and tumor directed therapeutic strategy for patients with newly diagnosed oligometastatic prostate cancer. This trial, and others like it, represent the critical first step towards curative intent therapy for a patient population where palliation has been the norm.

Clinicaltrials.gov identifier: NCT03298087 (registration date: September 29, 2017).

BMC cancer. 2019 Apr 01*** epublish ***

Neil R Parikh, Claudia Huiza, Jill S Patel, Sonny Tsai, Nathisha Kalpage, May Thein, Sage Pitcher, Steve P Lee, Warren S Inouye, Mark L Jordan, Homayoon Sanati, Lida Jafari, Carol J Bennett, Greg E Gin, Amar U Kishan, Robert E Reiter, Michael Lewis, Ahmad Sadeghi, William J Aronson, Isla P Garraway, Matthew B Rettig, Nicholas G Nickols

Department of Radiation Oncology, UCLA, 200 UCLA Medical Plaza, Suite B265, Los Angeles, CA, 90095-6951, USA., Department of Urology, UCLA, 27-139 Center for Health Sciences, Los Angeles, CA, 90095, USA., VA Greater Los Angeles Healthcare System, Internal Medicine Service, Hematology/Oncology Section, 11301 Wilshire Blvd, Los Angeles, CA, 90073, USA., VA Long Beach Healthcare System, Radiation Oncology Service, 5901 East 7th Street, Long Beach, CA, 90822, USA., Department of Urology, UCI, 333 City Blvd W #2100, Orange, CA, 92868, USA., VA Long Beach Healthcare System, Internal Medicine Service, Hematology/Oncology Section, 5901 East 7th Street, Long Beach, CA, 90822, USA., VA Greater Los Angeles Healthcare System, Pathology Service, 11301 Wilshire Blvd, Los Angeles, CA, 90073, USA., VA Greater Los Angeles Healthcare System, Radiation Oncology Service, 11301 Wilshire Blvd, Los Angeles, CA, 90073, USA., Department of Radiation Oncology, UCLA, 200 UCLA Medical Plaza, Suite B265, Los Angeles, CA, 90095-6951, USA. .