{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T11:40:17Z","timestamp":1756294817520,"version":"3.44.0"},"reference-count":18,"publisher":"BMJ","issue":"8","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2022,8,9]]},"published-print":{"date-parts":[[2022,8]]},"abstract":"<jats:p>A young man in his 40s was evaluated in the emergency department for abdominal and right flank pain. A CT scan of the abdomen and pelvis showed a solid, well-circumscribed lesion measuring 7.1\u00d78.1\u00d75.4 cm, which was arising from the retroperitoneum and extending from the third portion of the duodenum towards the right kidney. A percutaneous core biopsy was obtained, demonstrating an atypical smooth muscle neoplasm suggestive of a low-grade leiomyosarcoma. The patient underwent surgery for an en-block resection of the mass and the final pathology confirmed a perivascular epithelioid cell neoplasm without significant pleomorphism, mitosis or necrosis. Our case adds to the small number of perivascular epithelioid cell tumour cases reported in the literature and we present it in order to increase our understanding of this tumour and to assist in its appropriate diagnosis and management.<\/jats:p>","DOI":"10.1136\/bcr-2022-250252","type":"journal-article","created":{"date-parts":[[2022,8,19]],"date-time":"2022-08-19T11:16:35Z","timestamp":1660907795000},"page":"e250252","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Perivascular epithelioid cell tumour-mimicking retroperitoneal leiomyosarcoma"],"prefix":"10.1136","volume":"15","author":[{"given":"Shirin","family":"Siddiqi","sequence":"first","affiliation":[{"name":"Surgery, Conemaugh Health System, Johnstown, Pennsylvania, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lusine","family":"Mesropyan","sequence":"additional","affiliation":[{"name":"Surgery, Banner University Medical Center South, Tucson, Arizona, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2022,8,19]]},"reference":[{"key":"2025082703582863000_15.8.e250252.1","doi-asserted-by":"crossref","first-page":"648","DOI":"10.5858\/133.4.648","article-title":"Perivascular epithelioid cell tumor","volume":"133","author":"Armah","year":"2009","journal-title":"Arch Pathol Lab Med"},{"doi-asserted-by":"publisher","key":"2025082703582863000_15.8.e250252.2","DOI":"10.1007\/s12105-011-0268-9"},{"doi-asserted-by":"publisher","key":"2025082703582863000_15.8.e250252.3","DOI":"10.1007\/s00428-007-0509-1"},{"key":"2025082703582863000_15.8.e250252.4","doi-asserted-by":"crossref","first-page":"100336","DOI":"10.1016\/j.jbo.2020.100336","article-title":"Primary perivascular epithelioid cell tumor (PEComa) in bone: a review of the literature and a case arising in the humerus with multiple metastases","volume":"26","author":"Zhong","year":"2021","journal-title":"J Bone Oncol"},{"doi-asserted-by":"crossref","unstructured":"Mangham D . World health organisation classification of tumours: pathology and genetics of tumours of soft tissue and bone: edited by C. D. M. Fletcher K. K. Unni and F. Mertens PP. 427, Lyon, France: IARC press, 2002, ISBN: 9-2832-2413-2, \u00a353.00. J Bone Joint Surg Br 2004:86\u2013B:466.doi::10.1302\/0301-620X.86B3.0860466b","key":"2025082703582863000_15.8.e250252.5","DOI":"10.1302\/0301-620X.86B3.0860466b"},{"key":"2025082703582863000_15.8.e250252.6","doi-asserted-by":"crossref","DOI":"10.1097\/MD.0000000000003890","article-title":"A systematic review: perivascular epithelioid cell tumor of gastrointestinal tract","volume":"95","author":"Chen","year":"2016","journal-title":"Medicine"},{"key":"2025082703582863000_15.8.e250252.7","doi-asserted-by":"crossref","first-page":"3524","DOI":"10.12998\/wjcc.v7.i21.3524","article-title":"Retroperitoneal perivascular epithelioid cell tumours: a case report and review of literature","volume":"7","author":"Touloumis","year":"2019","journal-title":"World J Clin Cases"},{"key":"2025082703582863000_15.8.e250252.8","doi-asserted-by":"crossref","first-page":"2624","DOI":"10.1016\/j.radcr.2021.06.020","article-title":"Multifocal retroperitoneal and pelvic PEComas mimicking liposarcoma: a case report and review of literature","volume":"16","author":"Yim","year":"2021","journal-title":"Radiol Case Rep"},{"doi-asserted-by":"publisher","key":"2025082703582863000_15.8.e250252.9","DOI":"10.1016\/j.crad.2012.10.021"},{"key":"2025082703582863000_15.8.e250252.10","first-page":"679","article-title":"Pancreatic PEComa (sugar tumor): MDCT and EUS features","volume":"10","author":"Baez","year":"2009","journal-title":"JOP"},{"key":"2025082703582863000_15.8.e250252.11","doi-asserted-by":"crossref","first-page":"252","DOI":"10.2214\/AJR.13.10909","article-title":"Imaging features of primary and metastatic malignant perivascular epithelioid cell tumors","volume":"202","author":"Tirumani","year":"2014","journal-title":"AJR Am J Roentgenol"},{"key":"2025082703582863000_15.8.e250252.12","first-page":"4380","article-title":"Histopathologic characteristics and immunotypes of perivascular epithelioid cell tumors (PEComa)","volume":"12","author":"Bao","year":"2019","journal-title":"Int J Clin Exp Pathol"},{"doi-asserted-by":"publisher","key":"2025082703582863000_15.8.e250252.13","DOI":"10.1097\/PAS.0000000000000133"},{"doi-asserted-by":"publisher","key":"2025082703582863000_15.8.e250252.14","DOI":"10.1097\/PAS.0000000000001119"},{"key":"2025082703582863000_15.8.e250252.15","doi-asserted-by":"crossref","first-page":"923","DOI":"10.1097\/PAS.0000000000000646","article-title":"Two subtypes of atypical leiomyoma: clinical, histologic, and molecular analysis","volume":"40","author":"Ubago","year":"2016","journal-title":"Am J Surg Pathol"},{"key":"2025082703582863000_15.8.e250252.16","first-page":"36","article-title":"Malignant Perivascular Epithelioid Cell Neoplasm (PEComa) of\u00a0the\u00a0Pelvis: A Case Report","volume":"6","author":"D'Andrea","year":"2016","journal-title":"Urol Case Rep"},{"doi-asserted-by":"publisher","key":"2025082703582863000_15.8.e250252.17","DOI":"10.3892\/ol.2016.5231"},{"key":"2025082703582863000_15.8.e250252.18","first-page":"215","article-title":"Hepatic PEcoma: an unusual tumor in an infrequent location","volume":"88","author":"S\u00e1nchez-G\u00e1lvez","year":"2020","journal-title":"Cir Cir"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2022-250252","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T10:58:42Z","timestamp":1756292322000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2022-250252"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,8]]},"references-count":18,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2022,8,19]]},"published-print":{"date-parts":[[2022,8]]}},"alternative-id":["10.1136\/bcr-2022-250252"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2022-250252","relation":{},"ISSN":["1757-790X"],"issn-type":[{"type":"electronic","value":"1757-790X"}],"subject":[],"published":{"date-parts":[[2022,8]]}}}