{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T03:37:30Z","timestamp":1769657850224,"version":"3.49.0"},"reference-count":10,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002649","name":"Yeungnam University","doi-asserted-by":"publisher","award":["222A580017"],"award-info":[{"award-number":["222A580017"]}],"id":[{"id":"10.13039\/501100002649","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>We report a rare case of primary renal adenosarcoma in a 26-year-old woman presenting with right flank pain. Contrast-enhanced computed tomography demonstrated a large, mixed solid and cystic mass confined to the renal pelvocalyceal system, closely mimicking a malignant renal tumor. Histopathologic examination revealed a biphasic tumor with phyllodiform architecture. Immunohistochemistry showed benign epithelial positivity for cytokeratin and focal malignant stromal positivity for smooth muscle actin and CD10; however, the tumor was negative for CD99, Wilm\u2019s tumor protein, SS18-SSX, BCOR, and estrogen\/progesterone receptors. These findings led to the diagnosis of primary renal adenosarcoma. This case highlights the diagnostic challenge of distinguishing this rare tumor from more common renal malignancies and underscores the importance of imaging\u2013pathologic correlation.<\/jats:p>","DOI":"10.3390\/diagnostics16030410","type":"journal-article","created":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T15:56:12Z","timestamp":1769615772000},"page":"410","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Renal Adenosarcoma Mimicking a Malignant Pelvocalyceal Tumor: An Interesting Imaging Case"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2128-3524","authenticated-orcid":false,"given":"Su Hong","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Radiology, Yeungnam University Medical Center, Yeungnam University College of Medicine, Daegu 42415, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8800-7690","authenticated-orcid":false,"given":"Hee Jung","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Pathology, Yeungnam University Medical Center, Yeungnam University College of Medicine, Daegu 42415, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"444","DOI":"10.1148\/radiol.13112617","article-title":"Clear cell renal cell carcinoma: Discrimination from other renal cell carcinoma subtypes and oncocytoma at multiphasic multidetector CT","volume":"267","author":"Young","year":"2013","journal-title":"Radiology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"339","DOI":"10.3348\/jksr.2009.60.5.339","article-title":"Urothelial Carcinoma of the Upper Urinary Tract: Staging and the Enhancement Pattern by Multidetector Row Spiral CT","volume":"60","author":"Hwang","year":"2009","journal-title":"J. Korean Soc. Radiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1111\/j.1440-1827.2011.02653.x","article-title":"So-called \u2018adenosarcoma\u2019 of the kidney: A novel adult renal tumor with a cystic appearance","volume":"61","author":"Sameshima","year":"2011","journal-title":"Pathol. Int."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1111\/his.14190","article-title":"When used together SS18\u2013SSX fusion-specific and SSX C-terminus immunohistochemistry are highly specific and sensitive for the diagnosis of synovial sarcoma and can replace FISH or molecular testing in most cases","volume":"77","author":"Zaborowski","year":"2020","journal-title":"Histopathology"},{"key":"ref_5","unstructured":"WHO Classification of Tumours Editorial Board (2022). WHO Classification of Tumours of the Urinary System and Male Genital Organs, IARC. [5th ed.]."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1016\/j.humpath.2007.08.008","article-title":"Mixed epithelial and stromal tumor of kidney with malignant transformation: Report of two cases and review of literature","volume":"39","author":"Jung","year":"2008","journal-title":"Hum. Pathol."},{"key":"ref_7","first-page":"707","article-title":"Mixed epithelial and stromal tumours of the kidney with malignant transformation: A clinicopathological study of four cases","volume":"54","author":"Cheng","year":"2022","journal-title":"Pathology"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1186\/s13000-014-0179-7","article-title":"Metanephric adenosarcoma: A rare case with immunohistochemistry and molecular analysis","volume":"9","author":"Su","year":"2014","journal-title":"Diagn. Pathol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1451","DOI":"10.1097\/00000478-200111000-00016","article-title":"Metanephric adenosarcoma in a young adult: Morphologic, immunophenotypic, ultrastructural, and fluorescence in situ hybridization analyses: A case report and review of the literature","volume":"25","author":"Picken","year":"2001","journal-title":"Am. J. Surg. Pathol."},{"key":"ref_10","first-page":"3861","article-title":"SYT-SSX is critical for cyclin D1 expression in synovial sarcoma cells: A gain of function of the t(X;18)(p11.2;q11.2) translocation","volume":"62","author":"Xie","year":"2002","journal-title":"Cancer Res."}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/3\/410\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T16:09:16Z","timestamp":1769616556000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/3\/410"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,28]]},"references-count":10,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["diagnostics16030410"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics16030410","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,28]]}}}