Imaging manifestation of metastatic tumors in nasal cavity and paranasal sinuses

Objective: To investigate the imaging manifestations of metastasis in the nasal cavity and paranasal sinuses. Methods: Twelve lesions of 10 patients with pathologically proved metastasis were retrospectively reviewed, including 6 renal clear cell carcinoma, 2 pulmonary adenocarcinoma, 1 colorectal carcinoma and 1 hepatic carcinoma. All the patients underwent CT and MRI scan. Among them, 9 patients had contrast enhanced MRI scan and 5 patients had dynamic contrast-enhanced MRI as well. The location, bone changes, shape, margin, density, signal intensity, and enhancement characteristics of the lesions were observed. Results: The metastasis involved spheno-ethmoid area(n = 3), ethmoid sinus (n = 2), maxillary sinus (n = 2), nasal cavity(n = 2), fronto-ethmoid area(n = 2) and sphenoid sinus (n = 1). All 12 metastatic lesions demonstrated bone destruction with tumor bone formation in 1 lesion. The CT displayed 10 metastases showed equal density, one mixed density was high, another form of low-density mixed. MR imaging showed equal signal in 9 lesions, while low-mixed signal in 3 lesions on T₁WI compared with grey matter were found. On T₂WI, 11 lesions showed high mixed signal and homogeneous low signal in 1 lesion. All 12 lesions demonstrated markedly heterogenous enhancement after intravenous administration of contrast media. Of 5 cases with dynamic contrast-enhanced MRI scanning, 4 lesions demonstrated wash-out time-signal intensity curve (TIC) pattern and 1 lesion demonstrated plateau pattern. Conclusions: Renal carcinoma is the most common primary tumor for nasal cavity and paranasal sinuses metastasis. A typical imaging finding is located in the ethmoid sinuses, the soft tissue mass surrounded with rich blood supply multiple sinuses and significant bone destruction. (authors)