Primitive Myxoid Mesenchymal Tumor of Infancy: A Report of a Further Case with Locally Aggressive Behavior

We report a case of an 8-month-old child with a primitive myxoid mesenchymal tumor of infancy arising in the thenar eminence. The lesion recurred after conservative excision and was ultimately nonresponsive to chemotherapy, necessitating partial amputation. The patient remains free of disease 5 years after this radical surgery. This is the 1st report of such a tumor since it was initially described by Alaggio and colleagues in 2006. The pathologic differential diagnosis is discussed.