Abstract

Background: There is a vast discrepancy between the incidence of skull base metastases reported in vivo and at autopsy. Asymptomatic character or unspecific symptoms make the diagnosis difficult, particularly in patients with no history of cancer. Our case illustrates a skull base metastasis from breast cancer, detected in a diagnostic process initiated by ophthalmologic examination.
Case Report: We report the case of a 53-year-old woman complaining of ptosis and diplopia, with concomitant loss of skin sensation within the right half of the forehead, and without any other worrisome symptoms or signs. Ophthalmic examination revealed impairment in eye movements, slight proptosis and corneal hypoesthesia on the right side, with normal pupillary light reflexes. The anterior and posterior segments of the eye were normal. Based on CT and MRI, an extensive tumor was detected, infiltrating the right orbit and the frontotemporal region of the skull base, and producing edema of the adjacent aspects of the brain. Aside from partial palsy of the oculomotor nerve and the ophthalmic division of the trigeminal nerve, no abnormalities were found on neurological examination. Explorative craniotomy and histopathological findings revealed a skull base metastasis from breast cancer.
Conclusions: Diplopia, ptosis, proptosis, and ophthalmic nerve sensory loss may be the only manifestation of a skull base metastasis. Careful ophthalmologic examination is crucial in early detection of this life-threatening condition.

Keywords: Magnetic Resonance Imaging, Fixation, Ocular, Eye Diseases - radiography, Breast Neoplasms - pathology, Skull Base Neoplasms - secondary