A Rare Cause of Nuchal Rigidity: Metastatic Triple-Negative Breast Cancer Involving the Skull and Upper Cervical Spine.

A 48-year-old female presented to the ED with worsening headache and neck pain for the past week. Her medical history is significant for recurrent left-sided triple-negative breast cancer (TNBC) with metastasis to the chest wall, liver, and lungs, initially diagnosed two years ago. She underwent a left-sided mastectomy and received radiation therapy and chemotherapy. Physical examination was remarkable for nuchal rigidity and photophobia. MRI of the brain with contrast was performed, and the results were consistent with the new calvarium, skull, and upper cervical spine osseous metastases without any intracranial metastatic disease. This case report presents a rare cause of nuchal rigidity and photophobia due to an uncommon metastatic pattern in a patient with TNBC.