Subtle signs of breast cancer as an important pitfall in mammographic interpretation. Establishing an accurate diagnosis in an equivocal case

Mammogram is the standard imaging modality for the early detection of breast cancer, and it has been shown to reduce disease-related mortality by up to 30%. Mammogram, however, has its limitations. It is reported that 10–30% of breast cancers may be missed on a mammogram. Delay in the diagnosis and treatment may adversely affect the prognosis of patients with breast cancer. We present a case of multifocal invasive early breast carcinoma, which was misinterpreted twice as intramammary lymph nodes, thus resulting in a delay in diagnosis for eighteen months. The tumors were detected incidentally after the patient presented to our Breast clinic for symptoms related to a concomitant benign lesion involving the same breast. We describe the tumors’ imaging features and discuss the possible reasons that likely led to repeated misinterpretation. Awareness of possible causes for missed breast cancer is necessary to avoid delay of treatment initiation that may adversely affect prognosis.