Giant cell arteritis and polymyalgia rheumatica as first manifestation of typical pulmonary carcinoid tumor.

Giant cell arteritis (GCA), a systemic vasculitis of unknown origin, may appear rarely as a paraneoplastic syndrome. Cases secondary to pulmonary neuroendocrine tumors have not been reported. A 75-year-old female developed prednisone-responsive GCA/polymyalgia rheumatica (PMR) shortly followed by syndrome of inappropriate antidiuretic hormone secretion. An 8 mm carcinoid lung tumor with positron emission tomography normal uptake was found. After a thoracoscopic tumor resection the patient experienced complete clinical and laboratory remission. This is the first report of GCA with PMR in the context of carcinoid lung tumor. It emphasizes the role of paraneoplastic vasculitis as a possible cause of GCA.