To describe oncological outcomes after progressive site-directed therapy (PSDT) in genuine and induced oligometasatic (OM)-castration-resistant prostate cancer (CRPC).
Thirty-seven patients with OM-CRPC treated with PSDT were retrospectively analyzed, and oncological outcomes and recurrence patterns on whole-body diffusion-weighted MRI (WB-DWI) were evaluated.
Twenty-two (59%) were classified as genuine OM-CRPC and 15 (41%) as induced OM-CRPC. A 50% decline in PSA after PSDT was observed in 21 (95%) genuine OM-CRPCs and 7 (47%) induced OM-CRPCs (p = 0.0005). At a median observation period of 7.3 months, median PSA progression-free survival were 10.9 months in the genuine OM-CRPCs and 4.8 months in the induced OM-CRPCs (p = 0.015). Among the patients who developed PSA progression after PSDT, 11 of 15 in the genuine OM-CRPCs (73%) and 11 of 14 in the induced OM-CRPCs (79%) underwent WB-DWI at PSA progression. The median numbers of newly detected metastases were 2 (range: 1-5) in the genuine OM-CRPCs and 4 (range: 1-40) in the induced OM-CRPCs (p = 0.049). Only one new metastasis appeared in 5 patients from the genuine OM-CRPCs (46%) and 1 from the induced OM-CRPCs (9.1%, p = 0.048). In 7 of 9 patients from the genuine OM-CRPCs (78%) and 7 of 8 patients from the induced OM-CRPCs (88%) who had bone metastases alone, the newly detected metastasis limited to the bone.
Genuine OM-CRPC had better oncological outcomes after PSDT than induced OM-CRPC, and the number of lesions detected at recurrence was limited. Induced OM-CRPC might be a disseminated condition with micrometastases at OM diagnosis.
International journal of urology : official journal of the Japanese Urological Association. 2022 Oct 31 [Epub ahead of print]
Soichiro Yoshida, Taro Takahara, Yuki Arita, Kazuma Toda, Koichiro Kimura, Motohiro Fujiwara, Hajime Tanaka, Minato Yokoyama, Yoh Matsuoka, Ryoichi Yoshimura, Yasuhisa Fujii
Department of Urology, Tokyo Medical and Dental University, Tokyo, Japan., Department of Biomedical Engineering, Tokai University School of Engineering, Kanagawa, Japan., Department of Diagnostic Radiology, Keio University School of Medicine, Tokyo, Japan., Department of Radiation Therapeutics and Oncology, Tokyo Medical and Dental University, Tokyo, Japan., Department of Diagnostic Radiology, Tokyo Medical and Dental University, Tokyo, Japan.