Autologous fat transfer-related calcifications and enhancement on contrast-enhanced mammography mimicking malignancy.

Autologous fat transfer (AFT) is increasingly used for breast augmentation and reconstruction and may produce benign post-procedural imaging findings that mimic malignancy. We report a case of AFT-related calcifications with associated enhancement on contrast-enhanced mammography (CEM), resulting in a false-positive workup. A 42-year-old woman underwent bilateral cosmetic AFT in 2023. In 2024, 1 year after the procedure, she presented with a palpable mass in the right breast. Full-field digital mammography (FFDM) showed no suspicious abnormality, and targeted ultrasound demonstrated no suspicious findings. In 2025, 2 years after AFT and 1 year after the initial negative assessment, she re-presented because the palpable concern persisted. A repeat FFDM revealed multiple new bilateral grouped calcifications. Supplemental ultrasound demonstrated multiple benign-appearing cystic changes without a suspicious sonographic finding. CEM demonstrated areas of non-mass enhancement associated with several calcification clusters. Subsequent stereotactic biopsy revealed fat necrosis with associated calcifications and fibrosis, confirming benign post-AFT changes. This case illustrates that AFT-related calcifications and enhancement may cause false-positive findings on CEM and may lead to unnecessary biopsy. Awareness of these possible findings and communication between clinicians regarding surgical history are vital to prevent unnecessary biopsy and patient anxiety.