Autologous fat grafting is commonly performed in reconstructive breast surgery but also increasingly in breast augmentation surgery. On the international level, we are witnessing an important increased confidence for this procedure. Nevertheless, it continues to raise questions on the risks of cancer. A 66-year-old patient benefited from a lipofilling to improve a latissimus dorsi flap breast reconstruction, 7 years after initial cancer management. Two years later, constant pain in the flap leads to reoperation. The flap showed a major retraction with histologically massive infiltration of the muscle by an undifferentiated carcinoma of breast origin. The tumor cells were displayed directly in contact with lipofilling inside the muscle. Without establishing any causal link between these 2 events, this case raises the question once more of the risks of breast cancer and encourages us to continue being careful.