Castration-resistant prostate cancer (CRPC) progresses clinically, radiographically, or biochemically despite castrate serum testosterone levels. However, prostate-specific antigen (PSA) kinetics are often emphasized in routine practice, and regular radiographic follow-up is not consistently performed. The clinical significance of radiographic progressive disease (rPD) at metastatic CRPC (mCRPC) diagnosis remains unclear. This study investigated the prognostic impact of rPD at mCRPC diagnosis on survival outcomes.
Imaging data from 108 patients with mCRPC after progression from metastatic castration-sensitive prostate cancer between 2000 and 2020 at Kanazawa University Hospital were retrospectively analyzed. Patients were classified based on the presence or absence of rPD at mCRPC diagnosis. Kaplan-Meier analyses and Cox proportional hazards models were used to analyze overall survival (OS) and prostate cancer-specific survival (PCSS) after mCRPC progression.
At the time of mCRPC diagnosis, 51 patients (47.2%) had rPD, which was associated with lower hemoglobin and higher levels of PSA, LDH, and ALP. rPD without PSA progression was observed in 7.8% of patients. Median OS after mCRPC progression was 22.8 and 80.1 months (p < 0.001), whereas median PCSS was 30.4 and 89.7 months (p < 0.001) in the rPD-positive and rPD-negative groups, respectively. Multivariable analysis identified rPD and ALP ≥ 130 IU/L as independent prognostic factors for worse OS and PCSS.
Radiographic progression at mCRPC diagnosis is an independent prognostic factor for poor survival. Reliance on PSA kinetics alone may underrecognize relevant progression, suggesting the importance of regular imaging follow-up. However, because PSA-based and radiographic assessments were not directly compared, this finding should be interpreted with caution.
International journal of urology : official journal of the Japanese Urological Association. 2026 Mar [Epub]
Hiroaki Iwamoto, Tomohiro Hori, Takahiro Inaba, Ryunosuke Nakagawa, Taiki Kamijima, Hiroshi Kano, Tomoyuki Makino, Renato Naito, Hiroshi Yaegashi, Takahiro Nohara, Kazuyoshi Shigehara, Kouji Izumi, Atsushi Mizokami
Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.