{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:53:20Z","timestamp":1785430400338,"version":"3.56.0"},"reference-count":23,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T00:00:00Z","timestamp":1778112000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82373415"],"award-info":[{"award-number":["82373415"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["82373415"],"award-info":[{"award-number":["82373415"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>RET fusions are rare but actionable oncogenic drivers in metastatic colorectal cancer (mCRC), occurring in a small molecular subset with limited clinical evidence for selective RET inhibition. We report a 77-year-old woman with mCRC harboring a rare TIMM23B::RET fusion who achieved durable benefit from selpercatinib after progression on capecitabine. Molecular profiling showed RAS\/BRAF wild-type, microsatellite-stable disease with a TIMM23B::RET fusion. Selpercatinib induced a marked decline in tumor markers and a sustained partial response on serial imaging. Treatment was complicated by grade 3 hepatotoxicity, requiring temporary interruption and dose reduction to 80 mg twice daily. Despite this, disease control was maintained without further grade \u2265 3 toxicity. At the time of writing, the patient remains on treatment with progression-free survival exceeding 14 months. To our knowledge, this is among the first detailed reports of mCRC harboring a TIMM23B::RET fusion with documented clinical benefit from selpercatinib. This case highlights the value of comprehensive genomic profiling and individualized toxicity management in rare molecular subsets of mCRC.<\/jats:p>","DOI":"10.3390\/curroncol33050271","type":"journal-article","created":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T09:03:37Z","timestamp":1778144617000},"page":"271","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Durable Response to Selpercatinib in Metastatic Colorectal Cancer Harboring a Novel TIMM23B::RET Fusion: A Case Report"],"prefix":"10.3390","volume":"33","author":[{"given":"Ziyan","family":"Tong","sequence":"first","affiliation":[{"name":"Department of Medical Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China"},{"name":"Zhejiang Provincial Clinical Research Center for CANCER, Hangzhou 310009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mengyuan","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China"},{"name":"Zhejiang Provincial Clinical Research Center for CANCER, Hangzhou 310009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shanshan","family":"Weng","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China"},{"name":"Zhejiang Provincial Clinical Research Center for CANCER, Hangzhou 310009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3922-9553","authenticated-orcid":false,"given":"Ying","family":"Yuan","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, Key Laboratory of Cancer Prevention and Intervention, Ministry of Education, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China"},{"name":"Zhejiang Provincial Clinical Research Center for CANCER, Hangzhou 310009, China"},{"name":"Cancer Center, Zhejiang University, Hangzhou 310058, China"},{"name":"Center for Medical Research and Innovation in Digestive System Tumors, Ministry of Education, Hangzhou 310009, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,7]]},"reference":[{"key":"ref_1","first-page":"229","article-title":"Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries","volume":"74","author":"Bray","year":"2024","journal-title":"CA Cancer J. 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