Cluster Headache and Pituitary Prolactinoma

Cluster headache (CH) is a primary headache by definition not caused by any known underlying structural pathology. However, symptomatic cases have been described, for example, tumors, particularly pituitary adenomas, malformations, and infections/inflammations. The evaluation of CH is an issue unresolved. A 46-year-old man presented with a 5-month history of side-locked attacks of an excruciating stabbing and boring left-sided pain located in the orbit. He satisfied the revised International Classification of Headache Disorders criteria for CH. His medical and family histories were unremarkable. A diagnosis of CH was made. The patient partially responded to symptomatic treatment. Owing to the relatively late onset of CH an enhanced magnetic resonance imaging was ordered to rule out an underlying lesion. It was performed after 1 month and displayed a pituitary adenoma. Evaluations revealed a prolactinoma. After treatment with bromocriptine, the headache attacks resolved completely. Although I cannot exclude an unintentional comorbidity, in my opinion, the co-occurrence of a prolactinoma with unilateral headache, in a hitherto headache-free man, points toward the fact that in this case the CH was caused or triggered by the prolactinoma. The headache attacks resolved completely after the bromocriptine treatment and the patient also remained headache free at the follow-up. The response of the headache to sumatriptan and other typical CH medications does not exclude a secondary form. Symptomatic CHs responsive to this therapy have been described. Associated cranial lesions such as tumours have been reported in CH patients and the attacks may be clinically indistinguishable from the primary form. Neuroimaging, preferably contrast-enhanced magnetic resonance imaging should always be considered in patients with cluster headache despite normal neurological examination. Late-onset cluster headache represents a condition that requires careful evaluation. Prolactinoma can present as cluster headache. doi: http://dx.doi.org/10.4021/jmc1379e