A case of infantile neuroblastoma with intramucosal metastasis in a paranasal sinus.

An 8-year-old boy with neuroblastoma of the right adrenal gland is reported. His initial treatment included chemotherapy and surgery, with complete response (CR) being achieved at the initial site. A metastatic lesion was found in the right maxillary sinus 32 months after his initial treatment. A mass in the right soft palate was detected and was clinically suspected of being a metastasis. The results of biopsy were negative and the differential diagnosis from the imaging studies of CT included odontogenic disease, fungal infection, paranasal sinus cyst or hematoma, and benign tumors. Open transantral biopsy was done under general anesthesia, revealing severe inflammation in the right maxillary sinus as well as bone erosion. The histopathological diagnosis was metastatic neuroblastoma from the adrenal lesion. The local field was irradiated with 20 Gy of linear accelerator (linac) radiation, then the local field was eradicated. Extensive skeletal metastases were subsequently found by bone scintigraphy. Despite further treatment his general condition deteriorated rapidly and he died 24 months after starting treatment. We review the previous reports and discuss metastasis to the sinuses.