Invasive lobular carcinoma (ILC) is the second most common histological type of breast cancer, accounting for approximately 5–15% of cases. It is characterized by an insidious tissue infiltration pattern, providing challenging clinical and radiological diagnosis. Additionally to its unique clinical, molecular biology, and pathological features, there are histological subclassifications that describe different proportions of neoplastic patterns, such as classic (less aggressive) and pleomorphic (more undifferentiated and aggressive). Such differences may imply different strategies of local-regional and systemic therapy.
KeywordsInvasive lobular carcinoma Systemic treatment Breast-conserving surgery Lobular patterns
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