Pathological feature of encapsulated papillary carcinoma in the right breast concurrent with granular cell tumor in the left breast:report of a case
ZHANG Xiaoying
LIU Peng
HAN Yan
Abstract：Objective To investigate the clinical and pathological features of encapsulated papillary carcinoma (EPC) of the breast and granular cell tumor (GCT). Methods A case of right breast EPC combined with left breast GCT was collected, and its pathological features and immunophenotype were summarized. Relevant literature was reviewed. Results Under the microscope, EPC showed tumor cells arranged in papillary and sieve-like patterns within a fibrous capsule, with mild to moderate nuclear atypia and rare mitotic figures. Immunohistochemistry showed ER (+++, 95%), PR (+++, 30%), HER-2 (0), negative for myoepithelial markers (p63, CK5/6, Calponin) in the fibrous capsule and papillary core, and a Ki-67 proliferation index of approximately 10%. GCT showed polygonal tumor cells with eosinophilic granules in the cytoplasm, small round nuclei, centrally located, with indistinct nucleoli and no mitotic figures. Immunohistochemistry showed S100 (+), CD68 (+), and CK (-). Conclusion The coexistence of EPC and GCT in the breast is a rare condition, and it is prone to misdiagnosis in needle biopsy specimens and intraoperative frozen sections. Familiarity with the pathological characteristics of these two tumors helps in accurate diagnosis and treatment guidance.
Keywords：BreastEncapsulated Papillary CarcinomaGranular Cell TumorPathological FeaturesDifferential Diagnosis
Publication Date：2025-09-28
Online Publishing Date：2025-11-13(First online date of this platform, not the publication date of the document)
Pages：4( 1178-1181 )