Primitive neuroectodermal tumor of maxilla in a 4-year-old child: A rare case report with update on molecular pathogenesis

Primitive neuroectodermal tumor (PNET) belongs to the class of malignant round cell tumor. PNETs show varying degree of neuroectodermal differentiation. They are one of the most common tumors of childhood occurring in bone and also within soft tissues. Light microscopy with the aid of immunohistochemical stains was suitable for the diagnosis. Immunohistochemistry plays a pivotal role in differentiating this tumor entity. The EWSR1-FLI1 fusion is present only in PNET cells and codes for oncogenic protein. In this article, we present a case of maxillary swelling in a 4-year-old girl child who was diagnosed with PNET. We have highlighted the challenges of diagnosing the round cell tumors.