Progressive Metastatic Breast Phyllodes Tumor Turns into Spindle Cell Sarcoma: Report of Two Cases and Review of the Literature

Background: Breast fibroepithelial lesions encompass a wide variety of tumors from benign fibroadenomas to malignant phyllodes tumors (PTs). Local recurrence was reported in 20% of all subgroups and 20-25% risk of distant metastasis though superaggressive tumors are rare. Two young patients with nonresponsive, frequent recurrences of phyllodes tumors turned into the aggressive metastatic sarcoma are presented. Case Presentation: Case 1: A 34-year-old married woman referred with the chief complaint of a mass and pain in her right breast. There was a 3cm well defined mass in right breast. An intermediate grade benign phyllodes tumor was confirmed in biopsy. Patient underwent surgical wide excision, radiotherapy. Three weeks later the mass recurred in her right breast with severe pain and nonproductive cough without hemoptysis. A single lung metastasis is conformed in the CT scan. Total mastectomy and thoracoscopic metastasectomy was performed and spindle cell sarcomas in both specimens is confirmed. Chemotherapy was done. Two weeks after chemotherapy she presented with multiple bilateral lung metastasises and thoracic wall involvement. No regression in metastasis was seen receiving the second line chemotherapeutic agents. Case 2: A 17-year-old young girl was referred to the breast clinic with a 2 cm firm mobile mass in left breast. The histopathology of the mass was benign phyllodes tumor. (1.5 cm margins) The tumor recurred 3 months later treated. During radiotherapy, the patient referred to the emergency department with the complaint of dyspnea and sever pleural effusion. The cytology reported malignant cells. CT-guided biopsy showed a high grade sarcoma. During chemotherapy, large ulcer in the site of the breast was appeared and mastectomy with Latissmus dorsi flap was performed and angiosarcoma was confirmed. Despite the second and third line chemotherapy the disease was progressed and multiple lung metastasis were confirmed in chest CT scan. Conclusion: It seems that some subtypes of breast sarcomas could have an extremely an aggressive behavior which threatens the life of the patients in a short period of time. Further studies is suggested to discriminate the aggressive subtypes at the first step.