Table 1.

Histological variants of invasive lobular carcinoma

Subtype	Histological features
Alveolar	Small cells arranged in more-or-less globular aggregate of 20 or more cells separated by thin bands of fibrous stroma.
Tubulo-lobular	Neoplastic cells form tubular, glandular structures. The best prognosis among all forms.
Solid	Solid sheets of uniform small cells showing lobular morphology.
	There are more pleomorphism and higher frequency of mitoses.
Pleomorphic	The more aggressive and worst prognosis.
	The histological pattern may mimic an undifferentiated ductal carcinoma. Cells are larger due to irregular nuclei with prominent nucleoli.
	Mitotic figures are frequent, disperse or in line, throughout the breast stroma. Apocrine or histiocytoid differentiation is common.