Definition of Breast, infiltrating lobular carcinoma of the

Breast, infiltrating lobular carcinoma of the : Infiltrating lobular carcinoma is the second most common type of invasive breast cancer next to infiltrating ductal carcinoma, accounting for 5 to 10% of breast cancer.

Infiltrating lobular carcinoma starts in the lobules, the glands that secrete milk, and then infiltrates surrounding tissue.

On a mammogram, a lobular carcinoma can look similar to a ductal carcinoma -- a mass with fine spikes radiating from the edges (spiculation).

However, on physical examination of the breast, a lobular carcinoma is usually not a hard mass like a ductal carcinoma but rather a vague thickening of the breast tissue.

Lobular carcinoma can occur in more than one site in the breast (as a multicentric tumor) or in both breasts at the same time (as bilateral lobular carcinoma).