More Than Meets the Finger - A Rare Pediatric Finger Mass

A 13 year-old female presented with a painless palpable abnormality at the base of the fifth finger. Ultrasound demonstrated a hypoechoic mass with scattered hyperechoic foci superficial to the flexor tendon. No significant vascularity was visualized on color Doppler images. On MRI, the mass demonstrated low signal on T1, heterogeneous signal on T2, and heterogeneous enhancement following contrast administration. Surgical resection was performed, with a pathologic diagnosis of calcifying aponeurotic fibroma. Calcifying aponeurotic fibroma is a rare benign tumor of the distal extremities primarily occurring in children, with a high rate of local recurrence. We will review the clinical presentation, imaging features, differential diagnosis and pathological features typical of this entity. While rare, it is important for radiologists to be aware of this diagnosis in order to guide appropriate treatment.