[Primitive neuroectodermal tumor/extraosseus Ewing sarcoma of the temporal bone].

The term primitive neuroectodermal tumor (PNET) should be included in the differential diagnosis of small round blue cell tumors, which come from the neural crest and explain their neuroectodermal character. This is one of the most indifferentiated histological types of malignant tumors. In the PNET family, we high light the Ewing's Sarcoma, that is frecuently located in bony sites and has a less frequent localization in soft tissues. We focus on one atypic case of PNET/Extraosseus Ewing's Sarcoma that involves the external auditory canal and infiltrates the temporal bone. Surgery followed by postoperative chemotherapy and radiation offers the best local control of the disease.