CT features in second cancers of the maxillary sinus.

Five patients with a second maxillary cancer (squamous cell carcinoma), which developed 6 to 17 years after initial treatment for the first cancer on the opposite side, were compared with 21 control cases with a primary cancer on the basis of computed tomography (CT) findings. Generally, the second cancer was found at an earlier stage. The specific CT findings of early sinus carcinoma were uneven soft tissue distribution in the antrum and tumor permeation with bone fragments remaining at the original tumor site. These findings may be helpful for distinguishing this cancer from benign chronic sinusitis and/or other malignant sinus disease. The pterygoid process, medial bony wall, and ethmoid sinus had a tendency to be spared in most of the 5 patients with second maxillary cancer compared to the 21 control cases.