Neglected giant benign phyllode tumor of the breast

A 51-year-old woman presented herself to the gynecology unit with an increase in volume of the right breast that appeared more than a year earlier. The ulcerating mass measured more than 30 cm. The patient was delayed in consulting due to the COVID-19 pandemic. On admission, she had an Eastern Cooperative Oncology Group performance-status (ECOG-PS) score of 4, albuminemia at 8 g/dl with a high level of C-reactive protein. ¹⁸F-FDG PET/CT was performed for staging a suspected malignant breast cancer. The maximum standardized uptake value (SUV_max) measured in the right breast tumor was 7.4 (volume-rendering images of 18F-FDG PET (A), CT (B), and fused PET/CT (C)). The pathologic examinations of the biopsies were benign. In the other breast, the 18F-FDG PET identified a 23-mm lesion whose biopsy found an invasive carcinoma ER-positive/Her2-positive. Although the anesthetic risk was high, it was decided to perform the surgery. A right mastectomy and left breast conservative surgery with sentinel-lymph-node resection were performed in the same time. The final pathologic examination confirmed a benign phyllode tumor of 36 cm on the right breast and an invasive Her2-positive breast cancer on the left. For the left breast, radiotherapy and adjuvant chemotherapy with APT [1] were performed then endocrine therapy. After the surgery, the patient quickly recovered an ECOG-PS of 0. This case highlights the fact that surgery remains the standard treatment for low-grade phyllode tumors.