Giant breast phyllodes tumor with silent thromboembolism: A case report

BACKGROUND: Phyllodes tumor (PT) is a solid fibroepithelial breast lesion with proliferation of stromal and epithelial elements, usually presents with a rapidly expanding feature. Venous thromboembolism (VTE) have been reported to increase the burden in terms of mortality and morbidity of malignant tumor, and associate with worsened survival. However, benign PTs with silent thromboembolism that have not yet been reported, we report an unusual case of massive benign PT that grew on the left side of the breast in a cauliflower‐shaped form and presented severe chronic blood loss and deep VTE. CASE: A 37‐year‐old woman with uncontrolled pain presented a rapidly enlarging left breast mass, measuring approximately 30 × 20 × 15 cm(3) that first started 25 years ago. color Doppler ultrasound showed a large mass lesion on the left breast and deep VTE, several enlarged lymph nodes in the left axilla and mediastinum, which presented a malignant character. However, the biopsies of the mass did not show evidence of malignancy and the pathology result was considered to be benign PT. The patient was treated with an inferior vena cava and anticoagulation, the operation was arranged according to the surgical procedure, the patient recovered very well after mastectomy. CONCLUSION: This case is unique in that the giant breast mass presented with malignant character, was eventually pathologically confirmed to be benign PT, and it's rare that the benign tumor accompanied with silent thromboembolism. This finding describes the atypia features of giant benign PT and reminds the surgeon to consider the factor of VTE and risk when encountering ulcerative benign breast tumor and avoid excessive treatment.