title: Lobular breast carcinoma metastasis to a superficial plexiform schwannoma as the first evidence of an occult breast cancer.
abstract: Tumor to tumor metastasis is a rare phenomenon, in which one, benign or malignant, tumor is involved by metastatic deposits from another. Most documented tumor to tumor metastases have been located intracranially, in which, in the majority of cases, either a breast or a lung carcinoma metastasized to a meningioma. Only 7 cases of metastases to schwannoma have so far been reported in the English literature, in 6 cases to an intracranial acoustic schwannoma and in a single case to a subcutaneous schwannoma. We present a case of dermal/subcutaneous plexiform schwannoma containing metastatic deposits of an occult lobular breast carcinoma, creating a unique schwannoma with epithelioid cells. Differential diagnosis of schwannoma with epithelioid cells includes malignant transformation of schwannoma and metastasis of a carcinoma or melanoma to schwannoma, epithelioid schwannoma, and schwannoma with glandular or pseudo glandular elements.
authors: Department of Pathology, Institute of Oncology, Ljubljana, Slovenia.
authors: Barbara
authors: B
authors: Gazic
authors: Joze
authors: J
authors: Pizem
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000737:chemistry / Q000188:drug therapy / Q000556:secondary*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D009382:Neoplasms, Unknown Primary / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D009442:Neurilemmoma / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D012878:Skin Neoplasms / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology*; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor