[Clinicopathological features of the mucocele-like lesions in the breast]

To study the clinical and pathological features of mucocele-like lesions in the breast.

Nine cases of mucocele-like lesions in the breast were reported for the morphological and immunohistochemical features, the differential diagnosis, and a literature review.

All nine cases were from female patients, aged 23 to 43 years (mean 34 years), clinically presented with palpable breast masses. Grossly, the lesions were multi-cystic with colloidal appearances. Histologically, the lesions consisted of multiple cysts filled with colloid, these cysts were lined with tubular, cuboidal or columnar epithelium. There were superimposed papillary epithelial hyperplasia in three cases and atypical ductal hyperplasia in one. Extravasated mucinous lakes were seen in the stroma, but without cellular component.

Mucocele-like lesions of the breast is a group of mostly benign disease, and the differential diagnosis should include mucinous carcinoma.