{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T18:36:11Z","timestamp":1789842971462,"version":"4.0.1"},"reference-count":16,"publisher":"American Medical Association (AMA)","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Surg"],"published-print":{"date-parts":[[2026,6,1]]},"abstract":"\n Importance<\/jats:title>\n Parastomal hernia (PSH) is one of the most common complications after permanent colostomy, yet there is ongoing debate regarding the effectiveness and indications of preventive measures.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To evaluate the effectiveness and safety of funnel-shaped mesh in preventing PSH over a 3-year follow-up period.<\/jats:p>\n <\/jats:sec>\n \n Design, Setting, and Participants<\/jats:title>\n The Chimney Trial was a randomized, single-blinded, multicenter study conducted at 4 university and central hospitals in Finland and 1 central hospital in Sweden. This study presents the 3-year follow-up results. Of 439 screened patients undergoing laparoscopic or robotic abdominoperineal excision or Hartmann procedure for rectal adenocarcinoma, 143 were randomized (68 to the mesh group and 67 to the control group). At 3 years, 50 patients in the mesh group and 51 in the control group were available for analysis; computed tomography (CT) scans were obtained in 44 and 39 patients, respectively. These data were analyzed from September 2025 to December 2025.<\/jats:p>\n <\/jats:sec>\n \n Intervention<\/jats:title>\n Placement of a funnel-shaped parastomal mesh vs no mesh at the time of abdominoperineal excision or Hartmann procedure.<\/jats:p>\n <\/jats:sec>\n \n Main Outcomes and Measures<\/jats:title>\n CT-confirmed PSH at 3-year follow-up.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n The Chimney Trial included a total of 101 patients (39 female [39%] and 63 male [61%]). At 3 years, CT-confirmed PSH was observed in 25 of 44 patients (57%) in the mesh group and 32 of 39 patients (82%) in the control group (difference, \u201325%; 95% CI, \u201342% to \u20135%;\n P<\/jats:italic>\n \u2009=\u2009.001). Clinically diagnosed PSH occurred in 5 of 50 patients (10%) vs 20 of 51 patients (39%) in the control group (difference, \u201329%; 95% CI, \u221244% to \u201313%;\n P<\/jats:italic>\n \u2009&amp;lt;\u2009.001). PSHs were significantly larger in the control group compared with the mesh group (median [IQR], 86.8 [53.0-136.5] mL for the mesh group vs 185.9 [118.0-411.2] mL for the control group;\n P<\/jats:italic>\n \u2009=\u2009.003). No significant differences were observed in other secondary outcomes.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusions and Relevance<\/jats:title>\n In this study, funnel-shaped mesh significantly reduced PSH incidence without increasing complications over a 3-year follow-up period. These findings support the use of a funnel-shaped mesh as an effective and safe preventive strategy to reduce the risk of parastomal hernia after permanent colostomy.<\/jats:p>\n <\/jats:sec>\n \n Trial Registration<\/jats:title>\n \n ClinicalTrials.gov Identifier:\n NCT03799939<\/jats:ext-link>\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1001\/jamasurg.2026.1036","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T15:30:46Z","timestamp":1776871846000},"page":"584","source":"Crossref","is-referenced-by-count":5,"title":["Prevention of Parastomal Hernia With Funnel-Shaped Intra-Abdominal Mesh vs No Mesh for Rectal Adenocarcinoma Surgery"],"prefix":"10.1001","volume":"161","author":[{"given":"Elisa","family":"M\u00e4k\u00e4r\u00e4inen","sequence":"first","affiliation":[{"name":"Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jyri","family":"J\u00e4rvinen","sequence":"additional","affiliation":[{"name":"Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jyrki","family":"K\u00f6ssi","sequence":"additional","affiliation":[{"name":"P\u00e4ij\u00e4t-H\u00e4me Central Hospital, Lahti, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maziar","family":"Nikberg","sequence":"additional","affiliation":[{"name":"Department of Surgery and Centre for Clinical Research, Region V\u00e4stmanland Hospital, V\u00e4ster\u00e5s, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heikki","family":"Wiik","sequence":"additional","affiliation":[{"name":"Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monika","family":"Carpelan-Holmstr\u00f6m","sequence":"additional","affiliation":[{"name":"Helsinki University Hospital, Helsinki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tarja","family":"Pinta","sequence":"additional","affiliation":[{"name":"Sein\u00e4joki Central Hospital, Sein\u00e4joki, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kirsi","family":"Lehto","sequence":"additional","affiliation":[{"name":"Tampere University Hospital, Tampere, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marko","family":"Nikki","sequence":"additional","affiliation":[{"name":"Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pasi","family":"Ohtonen","sequence":"additional","affiliation":[{"name":"Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tero","family":"Rautio","sequence":"additional","affiliation":[{"name":"Oulu University Hospital, Medical Research Center Oulu, Oulu, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10","reference":[{"issue":"12","key":"soi260017r1","doi-asserted-by":"publisher","first-page":"1356","DOI":"10.1001\/archsurg.139.12.1356","article-title":"Preventing parastomal hernia with a prosthetic mesh.","volume":"139","author":"J\u00e4nes","year":"2004","journal-title":"Arch Surg"},{"issue":"10","key":"soi260017r2","doi-asserted-by":"publisher","first-page":"O191","DOI":"10.1111\/codi.13065","article-title":"Prophylactic mesh at end-colostomy construction reduces parastomal hernia rate: a randomized trial.","volume":"17","author":"Lambrecht","year":"2015","journal-title":"Colorectal Dis"},{"issue":"3","key":"soi260017r3","doi-asserted-by":"publisher","first-page":"427","DOI":"10.1097\/SLA.0000000000002542","article-title":"Use of prophylactic mesh when creating a colostomy does not prevent parastomal hernia: a randomized controlled trial-STOMAMESH.","volume":"269","author":"Odensten","year":"2019","journal-title":"Ann Surg"},{"issue":"6","key":"soi260017r4","doi-asserted-by":"publisher","first-page":"928","DOI":"10.1097\/SLA.0000000000004371","article-title":"End colostomy with or without mesh to prevent a parastomal hernia (GRECCAR 7): a prospective, randomized, double blinded, multicentre trial.","volume":"274","author":"Prudhomme","year":"2021","journal-title":"Ann Surg"},{"issue":"1","key":"soi260017r5","doi-asserted-by":"publisher","first-page":"38","DOI":"10.1097\/SLA.0000000000005537","article-title":"No reduction in parastomal hernia rate 3 years after stoma construction with prophylactic mesh: three-year follow-up results from STOMAMESH\u2013a multicenter double-blind randomized controlled trial.","volume":"277","author":"Ringblom","year":"2023","journal-title":"Ann Surg"},{"key":"soi260017r6","doi-asserted-by":"publisher","first-page":"243","DOI":"10.1007\/s10029-007-0318-0","article-title":"Prevention of parastomal hernias by prophylactic use of a specially designed intraperitoneal onlay mesh (Dynamesh IPST).","volume":"12","author":"Berger","year":"2008","journal-title":"Hernia"},{"issue":"1","key":"soi260017r7","doi-asserted-by":"publisher","first-page":"151","DOI":"10.1007\/s10029-015-1380-7","article-title":"Prevention of parastomal hernias with 3D funnel meshes in intraperitoneal onlay position by placement during initial stoma formation.","volume":"20","author":"K\u00f6hler","year":"2016","journal-title":"Hernia"},{"issue":"1","key":"soi260017r8","doi-asserted-by":"publisher","first-page":"41","DOI":"10.1186\/s12893-017-0237-7","article-title":"Preventing parastomal hernias with systematic intraperitoneal specifically designed 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