In situ lobular neoplasia of the breast with marked myoepithelial proliferation

Sami Shousha (1)

1 Histopathology

Aims: To present four new cases of in situ lobular neoplasia associated with marked proliferation of myoepithelial cells Methods and Results: Four recently seen cases showing extensive foci of in situ lobular neoplasia, as confirmed by negative E-Cadherin staining, were stained for myoepithelial cells using CD10, smooth muscle actin and cytokeratin 5/6. Invasive lobular carcinoma was also present in two cases, one case was associated with multiple foci of collagenous spherulosis and one was associated with a radial scar. Marked myoepithelial proliferation was seen around most of the in situ lobular foci or mingled with lobular cells. Conclusions: Marked proliferation of myoepithelial cells is sometimes encountered in association with extensive in situ lobular neoplasia. It is suggested that this proliferation might have a role in maintaining the in situ status of these lesions or, alternatively, that there is a shared factor responsible for the simultaneous proliferation of certain 'lobular' cell types and myoepithelial cells.

Mots clés: Medicine

Sami Shousha. In situ lobular neoplasia of the breast with marked myoepithelial proliferation. Histopathology, 2011, 58 (7), pp.1081. ⟨10.1111/j.1365-2559.2011.03838.x⟩. ⟨hal-00655192⟩