Patient presents with a palpable breast mass. Imaging shows a well-circumscribed lesion.
Case Discussion
Mucinous (or colloid) carcinoma is a rare histological subtype of breast cancer, accounting for 0.8-6% of breast cancers. It is more common in post-menopausal women. The lesion is usually well-circumscribed with a glistening, gelatinous cut surface. Microscopically, it is characterized by islands of neoplastic cells floating within lakes of extracellular mucin. It is mostly ER and PR positive, with rare overexpression of HER2(
Image Contributors
Lou, S., Chang, M.
Cite
Lou, S., Chang, M. Breast, Mucinous carcinoma. Digital Laboratory Medicine Library, Dept of Laboratory Medicine & Pathobiology, University of Toronto. Published
. Accessed December 17, 2025. https://dev.dlml.cflabs.ca/image/breast-mucinous-carcinoma-lmp66080
