{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T22:44:22Z","timestamp":1792622662150,"version":"4.5.0"},"reference-count":38,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,3]],"date-time":"2025-07-03T00:00:00Z","timestamp":1751500800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Society for the Promotion of Science (JSPS)","award":["24K02576"],"award-info":[{"award-number":["24K02576"]}]},{"name":"Japan Society for the Promotion of Science (JSPS)","award":["24K12434"],"award-info":[{"award-number":["24K12434"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>Radiation therapy, including external-beam radiation therapy (EBRT) and brachytherapy, is curative for localized prostate cancer. Hydrogel spacer (HS) placement between the rectum and prostate is popular for reducing radiation-related complications. Criteria to identify patients who benefit from HS placement would be clinically valuable. In a retrospective analysis of 430 patients with localized prostate cancer treated between November 2010 and March 2023 with \u22652 years of follow-up, we evaluated the incidence of rectal hemorrhage and its association with the median distance at the midpoint between the prostate and the rectum (mDPR) on pretreatment MRI. Rectal hemorrhage occurred in 6% of HS cases and 18% of non-HS cases (p &lt; 0.001). Among 268 patients who received EBRT (\u00b1brachytherapy), the incidence was 9% with HS and 30% without HS (p &lt; 0.001). In non-HS cases, the rate in patients with mDPR \u2264 1.62 mm was higher than in those with mDPR &gt; 1.62 mm (24% vs. 12%, respectively; p = 0.04). In patients with EBRT and mDPR \u2264 1.62 mm, HS significantly reduced hemorrhage (9% vs. 39%, respectively; p &lt; 0.001). Multivariate analysis identified mDPR and HS as independent predictors of rectal hemorrhage (both p = 0.02). Thus, HS placement may be safely omitted in non-EBRT cases with mDPR \u2265 1.62 mm.<\/jats:p>","DOI":"10.3390\/curroncol32070385","type":"journal-article","created":{"date-parts":[[2025,7,3]],"date-time":"2025-07-03T06:54:16Z","timestamp":1751525656000},"page":"385","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Patients with a Short Distance Between the Prostate and the Rectum Are Appropriate Candidates for Hydrogel Spacer Placement to Prevent Short-Term Rectal Hemorrhage After External-Beam Radiotherapy for Prostate Cancer"],"prefix":"10.3390","volume":"32","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1676-7404","authenticated-orcid":false,"given":"Shunsuke","family":"Owa","sequence":"first","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takeshi","family":"Sasaki","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akito","family":"Taniguchi","sequence":"additional","affiliation":[{"name":"Department of Radiology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuki","family":"Omori","sequence":"additional","affiliation":[{"name":"Department of Radiology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taketomo","family":"Nishikawa","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Momoko","family":"Kato","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shinichiro","family":"Higashi","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8361-0805","authenticated-orcid":false,"given":"Yusuke","family":"Sugino","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutaka","family":"Toyomasu","sequence":"additional","affiliation":[{"name":"Department of Radiology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Akinori","family":"Takada","sequence":"additional","affiliation":[{"name":"Department of Radiology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0320-977X","authenticated-orcid":false,"given":"Kouhei","family":"Nishikawa","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshihito","family":"Nomoto","sequence":"additional","affiliation":[{"name":"Department of Radiology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takahiro","family":"Inoue","sequence":"additional","affiliation":[{"name":"Department of Nephro-Urologic Surgery and Andrology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu 514-8507, Mie, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1088","DOI":"10.1007\/s10147-024-02575-3","article-title":"Urological cancer statistics on incidence from 1975 to 2019 and mortality from 1958 to 2022 in Japan","volume":"29","author":"Sasaki","year":"2024","journal-title":"Int. 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