{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T05:01:49Z","timestamp":1781154109719,"version":"3.54.1"},"reference-count":18,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T00:00:00Z","timestamp":1781136000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:p>Granular cell tumor of the breast (GCTB) is a rare Schwann-cell-derived neoplasm whose multimodal imaging features overlap extensively with those of invasive carcinoma, frequently exposing patients to unnecessarily extensive surgery in the absence of preoperative tissue diagnosis. We report two institutional cases with detailed imaging\u2013pathology correlation. In Case 1, a 53-year-old postmenopausal woman with a 2.5-cm left axillary tail mass displayed convergent malignant-pattern features across all three imaging modalities \u2014 a BI-RADS 5 spiculated mass with skin retraction on mammography, marked posterior acoustic shadowing on ultrasound, and heterogeneous enhancement with a type II (plateau) kinetic curve on contrast-enhanced MRI (a pattern associated with intermediate-to-high suspicion for malignancy) \u2014 together with an ipsilateral axillary lymph node demonstrating type III (washout) kinetics. The composite preoperative picture was clinically indistinguishable from cT2N1M0 invasive carcinoma. After the patient declined preoperative core needle biopsy (CNB), breast-conserving surgery and sentinel lymph node biopsy were performed; final pathology confirmed benign GCTB (S-100+, SOX10+, CD68+, Pan-CK\u2212, GATA3\u2212, ER\/PR\/AR\u2212; 0 of 6 Fanburg-Smith criteria) with reactive nodal hyperplasia. In Case 2, a 38-year-old premenopausal woman with a 0.9-cm right breast nodule underwent ultrasound-guided vacuum-assisted biopsy (VAB) yielding benign GCTB; histology demonstrated tumor cells encircling peripheral nerve bundles within the lesion \u2014 direct morphological evidence supporting the established Schwann-cell origin of the tumor. Both patients remained disease-free at 12 and 36 months. These cases reinforce that preoperative CNB with a targeted immunohistochemistry panel \u2014 explicitly distinguishing GCTB from ectopic axillary breast carcinoma \u2014 should be strongly recommended for any suspicious axillary tail mass; Case 1, in which the patient declined CNB and proceeded directly to surgery, illustrates by counter-example the diagnostic uncertainty that results when this step is omitted. We present these cases in accordance with the CARE reporting guidelines.<\/jats:p>","DOI":"10.3389\/fonc.2026.1888898","type":"journal-article","created":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T04:39:13Z","timestamp":1781152753000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Granular cell tumor of the axillary tail mimicking node-positive breast carcinoma \u2014 two cases with imaging\u2013pathology correlation"],"prefix":"10.3389","volume":"16","author":[{"given":"Yuming","family":"Shao","sequence":"first","affiliation":[{"name":"Department of Breast and Thyroid Surgery, Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao University","place":["Jinan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of General Surgery, Rushan People\u2019s Hospital","place":["Rushan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shasha","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Pathology, Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao University","place":["Jinan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of General Surgery, Rushan People\u2019s Hospital","place":["Rushan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine, Shandong Provincial Maternal and Child Health Care Hospital Affiliated to Qingdao University","place":["Jinan, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,11]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1007\/BF02078314","article-title":"\u00dcber myome, ausgehend von der quergestreiften willk\u00fcrlichen muskulatur","volume":"260","author":"Abrikossoff","year":"1926","journal-title":"Virchows Arch Pathol Anat"},{"key":"B2","doi-asserted-by":"publisher","first-page":"97","DOI":"10.1016\/j.suronc.2009.12.001","article-title":"Granular cell tumour of the breast","volume":"20","author":"Brown","year":"2011","journal-title":"Surg Oncol"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1016\/j.prp.2020.152865","article-title":"Granular cell tumor: a study of 42 cases and systemic review of the literature","volume":"216","author":"Mobarki","year":"2020","journal-title":"Pathol Res Pract"},{"key":"B4","doi-asserted-by":"publisher","first-page":"3533","DOI":"10.1038\/s41467-018-05886-y","article-title":"Loss-of-function mutations in ATP6AP1 and ATP6AP2 in granular cell tumors","volume":"9","author":"Pareja","year":"2018","journal-title":"Nat Commun"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1111\/j.1075-122X.2004.21525.x","article-title":"Granular cell tumor of the breast: a series of 17 cases and review of the literature","volume":"10","author":"Adeniran","year":"2004","journal-title":"Breast J"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1002\/jso.2930130405","article-title":"Granular cell tumor: a clinicopathologic study of 110 patients","volume":"13","author":"Lack","year":"1980","journal-title":"J Surg Oncol"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1093\/jbi\/wbab041","article-title":"Granular cell tumor of the breast: radiologic\u2013pathologic correlation","volume":"3","author":"Ghannam","year":"2021","journal-title":"J Breast Imaging"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1590\/0100-3984.2019.0056","article-title":"Granular cell tumor of the breast: correlations between imaging and pathology findings","volume":"53","author":"Abreu","year":"2020","journal-title":"Radiol Bras"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1186\/1477-7819-11-217","article-title":"A case of breast cancer in the axillary tail of Spence \u2014 enhanced magnetic resonance imaging and positron emission tomography for diagnostic differentiation and preoperative treatment decision","volume":"11","author":"Okubo","year":"2013","journal-title":"World J Surg Oncol"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1093\/jscr\/rjae531","article-title":"Challenges in diagnosis and management of invasive ductal carcinoma in axillary ectopic breast tissue: a case study","volume":"2024","author":"Suliman","year":"2024","journal-title":"J Surg Case Rep"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.12998\/wjcc.v11.i33.8044","article-title":"Granular cell tumor of the breast: a case report and review of literature","volume":"11","author":"Yan","year":"2023","journal-title":"World J Clin cases"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1097\/00000478-199807000-00001","article-title":"Malignant granular cell tumor of soft tissue: diagnostic criteria and clinicopathologic correlation","volume":"22","author":"Fanburg-Smith","year":"1998","journal-title":"Am J Surg Pathol"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1002\/cncr.24396","article-title":"Perineural invasion in cancer: a review of the literature","volume":"115","author":"Liebig","year":"2009","journal-title":"Cancer"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1148\/radiol.12110619","article-title":"Positive predictive value of BI-RADS MR imaging","volume":"264","author":"Mahoney","year":"2012","journal-title":"Radiology"},{"key":"B15","doi-asserted-by":"publisher","first-page":"37","DOI":"10.1016\/j.humpath.2015.09.035","article-title":"The role of GATA3 in breast carcinomas: a review","volume":"48","author":"Asch-Kendrick","year":"2016","journal-title":"Hum Pathol"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.5858\/2010-0430-OAR.1","article-title":"Recurrence risk and margin status in granular cell tumors of the breast: a clinicopathologic study of 13 patients","volume":"135","author":"Papalas","year":"2011","journal-title":"Arch Pathol Lab Med"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1016\/j.prp.2010.12.006","article-title":"Malignant granular cell tumor: a look into the diagnostic criteria","volume":"207","author":"Nasser","year":"2011","journal-title":"Pathol Res Pract"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.3390\/medicina57111260","article-title":"Efficacy and safety of vacuum-assisted excision for benign breast mass lesion: a meta-analysis","volume":"57","author":"Yoo","year":"2021","journal-title":"Med (Kaunas)"}],"container-title":["Frontiers in Oncology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1888898\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T04:39:36Z","timestamp":1781152776000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1888898\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,11]]},"references-count":18,"alternative-id":["10.3389\/fonc.2026.1888898"],"URL":"https:\/\/doi.org\/10.3389\/fonc.2026.1888898","relation":{},"ISSN":["2234-943X"],"issn-type":[{"value":"2234-943X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,11]]},"article-number":"1888898"}}