First case of transformation for breast fibroadenoma to high-grade malignant cystosarcoma in an in vitro fertilization patient

Objective: To evaluate the possible malignant transformation of fibroadenoma of the breast in patients undergoing an IVF cycle. Design: Case report. Setting: Assisted reproduction center. Patient(s): A 41-year-old female patient undergoing assisted fertilization treatment. Intervention(s): The patient underwent fine needle aspiration biopsy that confirmed fibroadenoma before the IVF attempt. She started a short stimulation protocol with triptorelin and recombinant FSH. After the first unsuccessful IVF attempt, she underwent a second short ovarian stimulation protocol with triptorelin and urinary FSH and she become pregnant. At 17 weeks, due to an increase in volume of the fibroadenoma, an excisional biopsy was performed that showed a malignant phyllode tumor. Then she underwent quadrantectomy. Main Outcome Measure(s): Malignant transformation of breast fibroadenoma. Result(s): Cytologic examination of the first fine needle aspiration biopsy specimen showed a fibroadenoma of the breast; excisional biopsy showed a high-grade malignant cystosarcoma. Conclusion(s): Fibroadenoma was transformed into high-grade malignant cystosarcoma after ovarian stimulation in an IVF patient.