title: A case of lobular carcinoma in situ presenting as a solid mass.
abstract: A patient presented with a 2 cm lump in the lower outer quadrant of the left breast. Mammogram and ultrasonography showed a solid mass with a microlobulated contour, partially irregular border and microcalcifications. MRI showed an irregular mass with early enhancement and high signal intensity, and the late-phase image demonstrated a partial washout pattern. These findings suggest that the tumour was a malignant invasive carcinoma. Non-invasive ductal carcinoma was diagnosed after a fine needle aspiration and core needle biopsy followed by a partial breast excision and sentinel lymph node (SLN) biopsy. A pathological examination of the lesion displayed characteristic small monomorphic cells, solid proliferation and massive distension within the lobular unit. The tumour was immunohistochemically negative for E-cadherin and pure lobular carcinoma in situ (LCIS) was diagnosed. Pure LCIS is very rare and there have been no previous reports of pure LCIS forming a solid mass.
authors.affiliation: Department of Breast Surgery and, Mie University Hospital, Japan. zhang-x@clin.edic.mie-u.ac.jp
authors.forename: X
authors.initials: X
authors.lastname: Zhang
authors.forename: N
authors.initials: N
authors.lastname: Hanamura
authors.forename: M
authors.initials: M
authors.lastname: Yamasita
authors.forename: Y
authors.initials: Y
authors.lastname: Kashikura
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
authors.forename: S
authors.initials: S
authors.lastname: Taizo
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis* / Q000601:surgery; D002278:Carcinoma in Situ / Q000175:diagnosis* / Q000601:surgery; D018275:Carcinoma, Lobular / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D021701:Sentinel Lymph Node Biopsy; D016896:Treatment Outcome