Primitive Myxoid Mesenchymal Tumor of Infancy Involving Chest Wall in an Infant: A Case Report and Clinicopathologic Correlation.

Primitive myxoid mesenchymal tumor of infancy (PMMTI) is a rare mesenchymal tumor of early childhood characterized by aggressive local infiltration of surrounding structures, rare metastases, and poor response to chemotherapy. Surgery alone appears to be the most effective treatment given the lack of predilection for metastasis and poor response to traditional chemotherapy. Below we report a patient with PMMTI successfully managed with surgery and observation and summarize the existing literature on histopathologic features and treatment of this lesion.