Year: 2025
Type: article
Study design: Case Report
Abstract: Neuroendocrine carcinomas of the breast are a rare subtype of invasive breast carcinomas, and those with morphologic and immunophenotypic features supporting Merkel cell carcinoma (MCC) are even more rare. Accurate diagnosis of these entities is important for clinical decision-making regarding the selection of optimal treatments. We report a patient withMCC in the deep breast parenchyma of a 52-year-old woman, without evidence of a cutaneous component. This tumor exhibited characteristic morphologic and immunophenotypic features of MCC, including sheets of high grade, hyperchromatic tumor cells, with perinuclear dot-like staining of keratin 20. To our knowledge, this is the sixth report of parenchymal breast MCC, and due to its rarity and aggressive course, we reviewed the literature, including prior experience on its diagnosis and management.
Authors: Kaitlyn J. Nielson, David J. Cook, Tina J. Hieken, Maria C. Olave, Malvika H. Solanki, Ruifeng Guo, Rafael E. Jimenez
Institutions: Mayo Clinic, Mayo Clinic in Florida
Language: English
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W4415380747