ENT Case 11. Nasal cavity mass from an elderly patient.

Small blue cell tumor in sinonasal cavity. The article by Dr. Lester Thompson about approach and differential diagnosis of small blue cell tumor in sinonasal tract is excellent. If you follow his approach, more than 95% of cases can be diagnosed without any difficulty. Initial workup panel includes: AE1/3, CAM 5.2, S100, synaptophysin, chromogranin, desmin, Myo-D1, CD45

The tumor cells in this case are diffusely positive for S100. Additional stains show that tumor cells are positive SOX10, HMB45 and Melan A.

Diagnosis: melanoma.