Typical cluster headache caused by granulomatous pituitary involvement.

A young woman had typical cluster headache attacks and a pituitary mass lesion. The headache attacks resolved after transsphenoidal resection of the tumour, which was diagnosed as a granulomatous inflammation. The association between cluster headache and granulomatous enlargement of the pituitary gland has never been described before. This case reinforces the growing evidence that even in typical cases of cluster headache, neuroimaging is mandatory to exclude structural lesions.