Malignant Transformation of Benign Phyllodes to Malignant Phyllodes Tumor

Abstract

INTRODUCTION: Malignant phyllodes tumor of the breast is a rare neoplasm for which clinical findings remain insufficient for determination of optimal management. Few cases have been published involving a malignant transformation of benign phyllodes to malignant phyllodes tumor. This is documented case of a transformation of benign to malignant phyllodes. Phyllodes tumors are rare fibroepithelial breast tumors, which are sometimes difficult to preoperative diagnoses and have unpredictable clinical outcome. These tumors must be suspected in patients with rapid-growing breast nodules, to avoid inappropriate management. CASE: A 23-year-old female patient presented a two-month history of palpable mass on the left breast, with accelerated growth in recent month. There were no personal or family history of breast cancer. This patient was submitted to the exeresis of a nodule in the left breast one year prior, where physical exam presented protruding and hardened palpable mass with 5x6 cm and she were given a histologically diagnosis of benign phyllodes tumor and periareolar scar. In this time, physical exam presented protruding and hardened palpable mass occupying the upper quadrants of the left breast. Signs of cutaneous involvement or axillary lymphadenomegaly were not evidenced. During the diagnostic investigation, the patient was submitted to mammography and ultrasound. Because of the extension of the lesions, patient underwent simple mastectomy with protesis without axillary dissection. Surgical margins were free of tumor. Macroscopy evidenced a lesion measuring 4,5x30 cm, and the anatomopathologic analysis of the surgical specimen confirmed the diagnosis of malignant phyllodes tumor. DISCUSSION: In our study malignant transformation was determined one year after operation, the outcome of cases with history of fibroadenoma or benign phyllodes are significantly better than that of cases without history of benign tumor but patients with malignant phyllodes tumors who exhibit rapid growth within 6 months require aggressive treatment.