Calcifying and osteoblastic tumors of the paranasal sinuses.

Calcifying and osteoblastic tumors of the paranasal sinuses comprise a large group of diseases, each characterized, however, by their own distinct pathologic features and correlated radiologic findings. The basic radiologic signs of such lesions comprise calcification, bone formation, and reactive bony sclerosis. It is the purpose of this presentation to define the radiologic signs which allow for appropriate diagnosis. These disorders are divided into three groups: calcifying and osteoblastic lesions simulating tumors, benign calcifying and osteoblastic tumors, and malignant calcifying and osteoblastic tumors.