Introduction
Primitive myxoid mesenchymal tumor of infancy (PMMTI) is a locally aggressive, treatment refractory soft-tissue sarcoma initially reported in 20061. Treatment is primarily surgical with more than two-thirds of the approximately 30 reported cases having undergone surgery alone. For those individuals in which a complete surgical resection is not feasible up front, morbidity is high, and event free survival is poor.2 Here we present the case of an infant with an unresectable PMMTI who is in remission and off therapy greater than two years following a combination of systemic chemotherapy, surgery and adjunctive proton beam radiation. Taken in conjunction with the eight previously reported cases for which systemic therapy was attempted, we propose an initial treatment strategy for patients with initially unresectable PMMTI.