Paraneoplastic bilateral proptosis in a case of non-small cell lung cancer

We report the case of a 51-year-old woman with a large cell bronchial carcinoma with neuroendocrine differentiation (T3N0M0, stage IIB) and bilateral exophthalmos. A CT of the orbitae was compatible with Graves ophthalmopathy, but neither abnormalities in thyroid function nor thyroid antibodies could be found. The proptosis normalized 10 days after tumor resection. We conclude that the most likely cause of the reversible proptosis in this patient is paraneoplastic, a condition not previously described in the English-language literature.