Metastatic Mammary Carcinoma to the Orbit Masquerading as Maxillary Sinusitis

Abstract

Introduction We report on a case of isolated metastatic breast cancer to the medial rectus muscle. This entity is exceedingly rare. Case A 44-year-old female with a history of breast cancer presented with unilateral maxillary symptoms and was treated for sinusitis. Over time, she developed ocular pain, diplopia, blurred vision and eventually complete adduction deficit. Results T1-weighted magnetic resonance imaging revealed a medial rectus lesion. Biopsy via transnasal transorbital endoscopic approach revealed metastatic mammary carcinoma. Discussion Metastatic disease to the orbit should be considered in the differential diagnosis of refractory maxillary sinus pain in patients with a known underlying malignancy.