Looking Beyond the Obvious: An Uncommon Intermammary Groove-Adjacent Breast Cancer Found on Screening Mammography

Breast cancer exhibits a high prevalence among women and represents a significant contributor to cancer-related mortality. Routine screening substantially reduces mortality rates by enabling the early detection of tumors. This report describes an uncommon case of breast cancer located deep near the intermammary groove in a 63-year-old woman. The tumor's asymptomatic presentation, small size, and atypical location posed a diagnostic challenge. However, screening mammography revealed a suspicious axillary adenopathy, prompting further evaluation. MRI identified a 6 mm intermammary groove-adjacent lesion, and a biopsy confirmed the cancer diagnosis. Staging excluded metastasis. The patient underwent neoadjuvant chemotherapy, and nearly a year later, MRI imaging showed total remission. Sentinel lymph node biopsy was negative for breast cancer, suggesting a favorable prognosis. This case highlights the importance of primary care, promoting screening programs, and early detection in improving prognosis. Enhanced access to screening and meticulous radiological interpretation are critical to optimizing patient outcomes.