Sinonasal esthesioneuroblastoma with intracranial extension: marginal tumor cysts as a diagnostic MR finding.

PURPOSE To determine whether the MR finding of cysts along the intracranial margin of sinonasal esthesioneuroblastomas can be considered to suggest this tumor. METHODS MR scans of 54 patients who had sinonasal lesions with intracranial extension were examined specifically for cysts along the intracranial margins of the lesions. RESULTS Only 3 of the 54 patients had these cysts, and all 3 of these patients had esthesioneuroblastoma. Surgical pathologic findings of one specimen showed the cyst to be marginally located within the tumor. CONCLUSION If cysts are seen on MR along the intracranial margin of a sinonasal mass, this finding highly suggests esthesioneuroblastoma.