{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T16:39:14Z","timestamp":1790095154044,"version":"4.0.1"},"reference-count":12,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,3,3]],"date-time":"2025-03-03T00:00:00Z","timestamp":1740960000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:sec><jats:title>Objectives<\/jats:title><jats:p>To evaluate the incidence and degree of rectal wall infiltration (RWI) of spacer gel used during prostate radiotherapy among two practitioners experienced in using rectal spacers.<\/jats:p><\/jats:sec><jats:sec><jats:title>Materials and methods<\/jats:title><jats:p>Consecutive patients with prostate cancer who received prostate radiotherapy after hydrogel rectal spacer insertion in August 2023\u2013August 2024 by two experienced practitioners were retrospectively included. Post-implant magnetic resonance imaging examinations were evaluated by two radiologists for RWI: 0 (no abnormality), 1 (rectal wall edema), 2 (superficial RWI), and 3 (deep RWI). Scores 2\u20133 were considered positive for RWI and their location and degree of RWI (radial, longitudinal, and circumferential) were also categorized. Inter-reader agreement was assessed with Cohen\u2019s Kappa.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>215 men were included. Agreement was substantial between the radiologists for RWI scores (Kappa, 0.697; 95% confidence interval, 0.594-0.800). RWI scores were 0 in 80.5% (173\/215), 1 in 7.9% (17\/215), 2 in 10.7% (23\/215), and, 3 in 0.9% (2\/215) of the men. Altogether, RWI was present (scores 2\u20133) in 11.6% (25\/215), most commonly in the mid-gland and apex with median radial, longitudinal, and circumferential involvement of 3.2\u00a0mm, 8.6\u00a0mm, and 11.5%. None of these patients demonstrated any significant rectal toxicity.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>RWI was very uncommon for experienced practitioners. The degree of RWI was focal and not associated with increased complications.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fonc.2025.1563015","type":"journal-article","created":{"date-parts":[[2025,3,3]],"date-time":"2025-03-03T07:04:14Z","timestamp":1740985454000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Low incidence of significant hydrogel spacer rectal wall infiltration: results from an experienced high-volume center"],"prefix":"10.3389","volume":"15","author":[{"given":"Sungmin","family":"Woo","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anton S.","family":"Becker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aaron 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