Delayed Diagnosis of Inflammatory Breast Cancer Presenting as Acute Mastitis in a Patient One Month Postpartum

Inflammatory breast cancer (IBC) is a rare yet aggressive form of invasive ductal carcinoma, with a poor prognosis and decreased 5-year survival rates. Characteristic findings for IBC include rapid onset of breast edema, peau d'orange appearance, and involvement of the breast skin. Additionally, diagnosis is confirmed with a skin punch biopsy. With such nonspecific features, IBC can be mistaken for benign etiologies, causing delays in diagnosis and treatment. This patient is a 44-year-old woman presenting with left breast swelling while concurrently breastfeeding. Following antibiotic treatment but no symptom resolution, the patient was referred out for further follow-up. Despite multiple imaging studies, suggesting benign findings, clinical suspicion prompted continued evaluation and finally diagnosis of triple-negative inflammatory breast cancer with distant metastases. Further awareness of the presentation of IBC and its mimicking of other disease processes such as mastitis is paramount to earlier detection and improved outcomes in future patients.