PMID- 33632163 OWN - NLM STAT- MEDLINE DCOM- 20211102 LR - 20211102 IS - 1472-6823 (Electronic) IS - 1472-6823 (Linking) VI - 21 IP - 1 DP - 2021 Feb 25 TI - A rare case of multiple endocrine neoplasia type 1 initially presenting as an asymptomatic, huge mediastinal mass: case report. PG - 31 LID - 10.1186/s12902-021-00695-9 [doi] LID - 31 AB - BACKGROUND: Multiple endocrine neoplasia type 1 (MEN1) is a rare inherited syndrome that concurrently involves various endocrine glands. We report a rare case of MEN1 in a 43-year-old man whose first manifestation was an asymptomatic mediastinal mass. CASE PRESENTATION: A 13-cm-sized mediastinal mass was diagnosed as an atypical thymic carcinoid by computed tomography and percutaneous needle biopsy. In addition, hypercalcemia from a left inferior parathyroid hyperplasia, and a non-functioning gastric neuroendocrine tumor seen on esophagogastroduodenoscopy were found. Therefore, the patient was clinically diagnosed with MEN1 syndrome, and underwent surgical resection of thymic carcinoid tumor after pre-operative concurrent chemoradiation therapy to decrease tumor size and volume. Parathyroid lesion and gastric neuroendocrine tumor were also removed. Finally, a MEN1 gene mutation was observed in the patient and his 7-year-old son. CONCLUSION: Despite its rare occurrence, thymic carcinoid tumor should be considered as a MEN1-associated tumor and necessitates screening of other endocrine glands. Thymic carcinoid tumor carries a poor prognosis in patients with MEN1, and thus it needs to be carefully monitored even after radical excision. FAU - Jun, Ji Eun AU - Jun JE AD - Department of Endocrinology and Metabolism, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, 892 Dongnam-ro, Gangdong-gu, Seoul, 05278, Republic of Korea. FAU - Hwang, You-Cheol AU - Hwang YC AD - Department of Endocrinology and Metabolism, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, 892 Dongnam-ro, Gangdong-gu, Seoul, 05278, Republic of Korea. FAU - Ahn, Kyu Jeong AU - Ahn KJ AD - Department of Endocrinology and Metabolism, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, 892 Dongnam-ro, Gangdong-gu, Seoul, 05278, Republic of Korea. FAU - Chung, Ho Yeon AU - Chung HY AD - Department of Endocrinology and Metabolism, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, 892 Dongnam-ro, Gangdong-gu, Seoul, 05278, Republic of Korea. FAU - Jeong, In-Kyung AU - Jeong IK AUID- ORCID: 0000-0001-7857-546X AD - Department of Endocrinology and Metabolism, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, 892 Dongnam-ro, Gangdong-gu, Seoul, 05278, Republic of Korea. jik1016@naver.com. LA - eng PT - Case Reports PT - Journal Article DEP - 20210225 PL - England TA - BMC Endocr Disord JT - BMC endocrine disorders JID - 101088676 SB - IM MH - Adult MH - *Asymptomatic Diseases MH - Humans MH - Male MH - Mediastinal Neoplasms/complications/*diagnostic imaging MH - Multiple Endocrine Neoplasia Type 1/complications/*diagnostic imaging MH - Thymoma/complications/*diagnostic imaging MH - Thymus Neoplasms/complications/*diagnostic imaging PMC - PMC7905909 OTO - NOTNLM OT - Case report OT - MEN1 OT - Multiple endocrine neoplasia OT - Thymic carcinoid tumor COIS- The authors have no competing interest to disclose. EDAT- 2021/02/27 06:00 MHDA- 2021/11/03 06:00 PMCR- 2021/02/25 CRDT- 2021/02/26 05:38 PHST- 2020/08/27 00:00 [received] PHST- 2021/02/09 00:00 [accepted] PHST- 2021/02/26 05:38 [entrez] PHST- 2021/02/27 06:00 [pubmed] PHST- 2021/11/03 06:00 [medline] PHST- 2021/02/25 00:00 [pmc-release] AID - 10.1186/s12902-021-00695-9 [pii] AID - 695 [pii] AID - 10.1186/s12902-021-00695-9 [doi] PST - epublish SO - BMC Endocr Disord. 2021 Feb 25;21(1):31. doi: 10.1186/s12902-021-00695-9.