Metastasis of breast cancer to the sphenoid sinus presenting as tolosa-hunt syndrome

Breast cancer with sphenoid sinus metastasis has rarely been reported. A 57-year-old woman presented with Tolosa-Hunt syndrome 1 year after undergoing surgery and chemoradiation therapy for ductal breast cancer. The diagnosis of Tolosa-Hunt syndrome was based on a computed tomography scan and granulomatous pathologic findings from the ethmoid sinuses. Magnetic resonance images revealed an enhanced soft tissue mass mainly in the right sphenoid sinus; the second sinoscopic biopsy revealed metastatic invasive ductal breast carcinoma with intact surface epithelium. The patient died 20 days after the second biopsy. In this report, we discuss the possible metastatic pathway and choice of imaging modalities for the diagnosis of this rare metastatic sphenoid sinus cancer.