1) Idiopathic granulomatous lobular mastitis (IGLM) is a benign inflammatory breast condition characterized by non-caseating granulomas within the breast lobules.
2) Diagnosis involves clinical presentation, imaging findings of masses or irregularities, and histopathological identification of granulomas on core needle biopsy.
3) While the exact cause is unknown, it is thought to be due to an inflammatory response triggered by extravasated secretions within breast tissue following micro-trauma from breastfeeding or milk stasis.