@article{oai:tsukuba.repo.nii.ac.jp:02001441,
 author = {Murakami, Motohiro and Ishikawa, Hitoshi and Shimizu, Shosei and Iwata, Hiromitsu and Okimoto, Tomoaki and Takagi, Masaru and Murayama, Shigeyuki and Akimoto, Tetsuo and Wada, Hitoshi and Arimura, Takeshi and Sato, Yoshitaka and 五所, 正彦 and GOSHO, Masahiko and Nakamura, Katsumasa and 櫻井, 英幸 and SAKURAI, Hideyuki},
 issue = {6},
 journal = {Cancers},
 month = {Jun},
 note = {Background: Androgen deprivation therapy (ADT) combined with radiation therapy benefits intermediate- and high-risk prostate cancer (PC) patients. The optimal ADT duration in combination with high-dose proton beam therapy (PBT) remains unknown. Methods: Intermediate- and high-risk PC patients treated with PBT combined with ADT for various durations were analyzed retrospectively. To assess the relationship between ADT and biochemical relapse-free (bRF) rate, Cox proportional hazards models including T stage, prostate specific antigen (PSA) level, Gleason score (GS), and total radiation dose were used. Results: In the intermediate-risk PC patients (n = 520), ADT use improved bRF (HR 0.49, 95% CI 0.26–0.93; p = 0.029), especially in those with multiple intermediate-risk factors (T2b–2c, PSA 10–20 ng/mL, and GS 7). In the high-risk PC patients (n = 555), a longer ADT duration (>6 months) conferred a benefit for bRF (HR 0.54, 95% CI 0.32–0.90; p = 0.018), which was most apparent in patients with multiple high-risk factors (T3a–4, PSA > 20 ng/mL, and GS ≥ 8) treated with ADT for ≥21 months. Conclusions: Short-term (≤6 months) ADT is beneficial for intermediate-risk PC patients, but likely unnecessary for those with a single risk factor, whereas ADT for >6 months is necessary for high-risk PC patients and ADT for ≥21 months might be optimal for those with multiple risk factors in combination of high-dose PBT.},
 title = {Optimal Androgen Deprivation Therapy Combined with Proton Beam Therapy for Prostate Cancer: Results from a Multi-Institutional Study of the Japanese Radiation Oncology Study Group},
 volume = {12},
 year = {2020},
 yomi = {ゴショ, マサヒコ and サクライ, ヒデユキ}
}