Malignant phyllodes tumor: double recurrence in a young patient

Abstract

Objective: To present a case of a dramatic evolution of malignant phyllodes tumor (PT) in a young patient, discussing
the importance of radiological findings for an early diagnosis and correct therapeutic approach. Methods: A 23-year-old
woman was admitted with a growing nodule in the left breast over a 5-month period, classified as BI-RADS 3 on mammography, evolving with hyperemia and local pain, leading to the hypothesis of mastitis. A solid-cystic lesion was seen on
ultrasound, and a biopsy of the solid component was performed. The possibility of PT was raised due to rapid evolution
and radiological findings, and the patient underwent tumorectomy, which indicated malignant PT. Four weeks later, the
patient returned with a lesion similar to the initial and subsequently underwent mastectomy. She returned after seven
weeks with lesions in the surgical wound, underwent a new tumorectomy, which indicated compromised margins in the
anatomopathological evaluation. She is currently undergoing radiotherapy. Results: PT is a rare subtype of breast tumors,
up to 2% of them. Most PTs are histologically benign, but when malignant, they have a higher recurrence and mortality
rate. It presents as a fast-growing unifocal mass in pre-menopausal women and can be classified as benign, borderline,
or malignant depending on its histological evaluation. The differentiation between PT and fibroadenoma, and between
the histological types of PT, is virtually indistinguishable on mammography and breast ultrasound, but in addition to the
clinical signs of fast evolution, breast magnetic resonance imaging can be useful in this aspect—appearing as hypointense
on T1, variable signal on T2, and early contrast enhancement. Conclusion: Although a definitive diagnosis is complex,
the diagnosis of PT, including its malignant variant, must be considered in the appropriate clinical-radiological context
in order to achieve early treatment and improve prognosis.