Sinonasal non-Hodgkin's lymphoma with skull base involvement

Non-Hodgkin's lymphoma (NHL) is a rare tumor of the skull base. As the inci dence of primary central nervous system (CNS) lymphoma has increased, atypi cal presentations involving the skull or cranial base exclusively have been reported. In immunocompetent patients with no previous history or predispo sing factors, the diagnosis of primary NHL of the skull base may be delayed . We present four cases of nasal and paranasal sinus NHL with both skull ba se and intracranial involvement in immunocompetent patients. Clinicopatholo gic correlation suggests that cranial base and intracranial involvement wit h NHL represents advanced-stage primary sinonasal disease. Surgical biopsy before definitive treatment is recommended. Radiation therapy provides loca l control; adjuvant chemotherapy after primary radiation therapy may be req uired for recurrent disease.