Headaches are a common complaint in the general population – 22% of women and 11% of men are estimated to suffer from them. While not as familiar, lesions of the sellar and parasellar region are also relatively common, but they are usually not symptomatic and often go undetected throughout life. Studies of cadavers and healthy volunteers give us an incidence that ranges from 1.7% to 27% in the general population.
When the two occur together, it is difficult to determine whether the headaches are caused by the lesion or if the two are occurring coincidentally. The prevalence of headaches is higher among patients with pituitary lesions than it is in the general population, and headache is often the symptom that leads previously undiagnosed patients to a physician in the first place. But there is not always a direct correlation and rates of headache improvement after surgery have not been evaluated in large cohorts.
This has important implications for counseling patients with pituitary lesions who have headaches but no other indications for surgery. “While we can be sure that symptoms like visual deficits and endocrine dysfunction are related to the tumor, evaluating a patient whose only complaint is headache is much more complicated,” says neurosurgeon Manish Aghi MD, PhD. Aghi led a recent study at the California Center for Pituitary Disorders that analyzed 961 patients treated over five years to determine factors that may predict whether headaches will improve following surgery. Just over a third of all patients in the study suffered from headaches and 73% of those patients described it as their primary symptom.
Headache was most common in patients with pituitary apoplexy (84%), followed by Rathke’s cleft cysts (60%), hypophysitis (50%), craniopharyngiomas (46%), and pituitary adenomas (28-29%). Women and younger patients were also more likely to present with headaches.
Most patients with headaches improved after surgery, but improvement was frequently delayed (11% reported improvement at 6-week follow-up and 53% reported improvement at 6-month follow-up). Patients with headache as their chief complaint, patients undergoing complete removal of their tumor, and patients with a shorter history of headache were more likely to experience postoperative improvement. Surprisingly, the size of the tumor or cyst was not a variable associated with headaches.
“Our finding that complete removal was associated with headache improvement and that headache improvement can take up to 6 months to occur will be important for endocrinologists and neurosurgeons to be cognizant of,” says Aghi.
To address these issues prospectively Aghi and his team are putting in place a clinical trial involving structured questionnaires like the Headache Impact Test (HIT-6) given before and after surgery, intraoperative measurements of pressure within the pituitary gland, and blood biomarkers to better identify patients whose headaches could be attributable to their pituitary tumor or cyst.