Pure mucinous adenocarcinoma of the breast with the rare lymphoplasmacytic infiltration: A case report with review of literature.

Key Clinical Message: A unique ER/PR-positive mucinous adenocarcinoma of breast but CK7/CK20 negativity. A rare finding of Lymphoplasmacytic Infiltration is noted. Successful treatment included modified radical mastectomy and tamoxifen-based therapy, leads to remission.