Cavernous sinus syndrome associated with metastatic colorectal cancer and perineural spread along the trigeminal nerve

Purpose We report the case of a patient with cavernous sinus syndrome associated with biopsy-confirmed metastasis from colorectal cancer. Observations A patient known for laryngeal carcinoma and metastatic colorectal carcinoma presented with symptoms of left trigeminal neuralgia and progressive, near-complete ophthalmoplegia. Magnetic resonance imaging (MRI) revealed a mass in the left cavernous sinus, extending into Meckel's cave with perineural spread along the mandibular branch of the left trigeminal nerve. A transsphenoidal biopsy was performed and demonstrated metastatic colon adenocarcinoma. We review the existing literature on colorectal cancer associated cavernous sinus syndrome. Conclusions and importance Cavernous sinus metastasis from colorectal cancer is exceedingly rare. We report the second case of this entity with histopathologic confirmation, and the first case with concurrent perineural spread involving the trigeminal nerve. Cavernous sinus metastasis may represent a poor prognostic factor in colorectal cancer.