title: Metastatic gastrinoma in the breast mimicking primary solid papillary carcinoma.
abstract: We report a case of metastatic gastrinoma to the breast morphologically mimicking solid papillary carcinoma of the breast. A 59-year-old woman presented with a hypoechoic right breast mass that histologically revealed solid nests of small monotonous tumor cells, fibrovascular cores, and round to oval nuclei with fine chromatin and small nucleoli. Immunohistochemistry demonstrated chromogranin and synaptophysin positivity. Tumor prognostic markers showed weak positivity for estrogen receptor and negativity for progesterone receptor. Although an initial diagnosis of solid papillary carcinoma was rendered, subsequent identification of the patient's clinical history of pancreatic gastrinoma and an additional immunohistochemical stain for gastrin supported a diagnosis of metastatic gastrinoma. We report this rare case to increase awareness of metastatic neuroendocrine tumors in the breast. Multiple breast lesions and lack of expression of estrogen/progesterone hormone receptors should prompt careful review of the patient's clinical history to rule out metastatic neuroendocrine disease.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS 66160.
authors.forename: Michael
authors.initials: M
authors.lastname: Burt
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS 66160.
authors.forename: Rashna
authors.initials: R
authors.lastname: Madan
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS 66160. Electronic address: ffan@kumc.edu.
authors.forename: Fang
authors.initials: F
authors.lastname: Fan
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D001943:Breast Neoplasms / Q000737:chemistry / Q000556:secondary*; D002291:Carcinoma, Papillary / Q000737:chemistry / Q000473:pathology*; D002864:Chromogranins / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D015408:Gastrinoma / Q000737:chemistry / Q000556:secondary*; D005755:Gastrins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000737:chemistry / Q000473:pathology*; D011237:Predictive Value of Tests; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D016708:Synaptophysin / Q000032:analysis
chemical_list: D014408:Biomarkers, Tumor; D002864:Chromogranins; D005755:Gastrins; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D016708:Synaptophysin
keywords: Breast; Estrogen receptor; Metastatic gastrinoma; Neuroendocrine tumor; Solid papillary carcinoma