Dual-timing PSA as a biomarker for patients with salvage intensity modulated radiation therapy for biochemical failure after radical prostatectomy

We investigated the outcomes and the associated clinical-pathological factors in patients with prostate cancer (PCa) undergoing salvage intensity modulated radiation therapy (IMRT) for post-radical-prostatectomy (RP) biochemical failure. We report clinical outcomes of post-RP salvage IMRT, and describe chronic toxicity in these patients.Fifty patients with PCa underwent post-RP salvage IMRT. The median dose of IMRT was 70 Gy to the prostatic and seminal vesicle bed. Clinical-pathological and toxicity information were collected. The prostate cancer-specific survival (PCSS), disease-free survival (DFS), and biochemical-failure-free survival (BFFS) were calculated. Prognostic factors were analyzed for their association with disease control.The median follow-up time was 74 months. The 5-year PCSS, DFS, and BFFS after salvage IMRT were 95%, 88%, and 60%, respectively. Two patients (4%) experienced late gastrointestinal toxicity ≥ grade 3, and 5 patients (10%) had late genitourinary toxicity ≥ grade 3. On multivariate analysis, post-RP prostate-specific antigen (PSA) nadir ≤0.1 ng/ml (P=0.018) and PSA ≤0.5 ng/ml at salvage IMRT (P=0.016) were independent factors predicting better BFFS. Patients with both post-RP PSA nadir ≤0.1 ng/ml and PSA ≤0.5 ng/ml at salvage IMRT had a 5-year BFFS of 83% as compared with 43% in other patients (P=0.001).In conclusion, with hormonal therapy in most PCa patients, the addition of salvage IMRT for post-RP biochemical failure can achieve a good outcome with low toxicity. Patients with a post-RP PSA nadir ≤0.1 ng/ml and PSA ≤0.5 ng/ml at salvage IMRT could benefit the most from salvage IMRT.

Oncotarget. 2016 Jun 14 [Epub ahead of print]

Yu-Jen Wang, Chao-Yuan Huang, Wei-Hsien Hou, Chia-Chun Wang, Keng-Hsueh Lan, Hong-Jen Yu, Ming-Kuen Lai, Shihh-Ping Liu, Yeong-Shau Pu, Jason Chia-Hsien Cheng

Department of Radiation Oncology, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan., Department of Urology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Division of Radiation Oncology, Department of Oncology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Division of Radiation Oncology, Department of Oncology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Division of Radiation Oncology, Department of Oncology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Department of Urology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Department of Urology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Department of Urology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Department of Urology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan., Division of Radiation Oncology, Department of Oncology, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan.