Infiltrating lobular carcinoma of the breast (ILC). Diagnostic and therapeutic aspects.

Invasive lobular carcinoma of the breast (ILC) is the second most common form of mammary neoplasm after ductal carcinoma. Due to its histological features, characterised by a diffuse infiltration of the tissue by malignant cells with scarce fibrotic reaction, lobular carcinoma often presents clinical and instrumental diagnostic difficulties. The Authors present a retrospective series of 28 patients with lobular carcinoma, with special regard to the diagnostic work-up. Clinical examination misdiagnosed 10 cases, in which only a mild thickening of the breast parenchyma was present. Mammographic false negatives were 21.4% (6 cases). Ultrasonography allowed correct diagnosis in 5 out of these 6 cases. Fine needle aspiration (FNA) had low sensitivity (33% false negatives). ILC constitutes a diagnostic challenge, often requiring the combination of multiple diagnostic tools.