Fibro-osseous pseudotumor of the digit: a case report

Fibro-osseous pseudotumor is a poorly reported benign ossifying tumor. Due to its aggressiveness and lack of specificity, the lesion has previously been mistaken for a malignant lesion, leading to unnecessary radical treatment. Our case warns our readers of the aggressiveness of the tumor and rational surgical planning. In our case, a 25-year-old male patient presented with a painless, enlarging mass in the left index finger that had developed over the course of 5 months. The lesion was first partially surgically removed for biopsy, which confirmed the lesion to be fibro-osseous pseudotumor. Considering the possibility of skin necrosis from complete excision, complete removal was postponed until the second surgery. However, the residual lesion rapidly progressed, reaching its original size within 4 months. Another lesionectomy was performed to thoroughly remove the recurrent lesion surrounding the joint capsules. The intraoperative frozen section again supported the initial diagnosis and recurrence. During the 2-year follow-up, there were no signs of recurrence, and the function of the finger was fully recovered. Fibro-osseous pseudotumor should be considered in the differential diagnosis of rapidly progressive lesions affecting the digits. Complete surgical excision is the treatment of choice. However, the surgical strategy should be cautiously planned because of the aggressiveness of fibro-osseous pseudotumor and the possibility of saving the involved digit.