Neurocognitive changes in pituitary adenoma patients after Gamma Knife radiosurgery

Altered hemispheric asymmetry of attentional networks in patients with pituitary adenoma: an event-related potential study

Background

Emerging evidence has been reported of attentional dysfunction in pituitary adenoma patients. However, the effect of pituitary adenomas on lateralized attention network efficiency remained to be clear. Thus, the present study aimed to investigate the impairment of lateralized attention networks in patients with pituitary adenoma.

Methods

Eighteen pituitary adenoma patients (PA group) and 20 healthy controls (HCs) were included in this study. Both behavioral results and event-related potentials (ERPs) were acquired while subjects performed the Lateralized Attention Network Test (LANT).

Results

Behavioral performances indicated the PA group had a slower reaction time and a similar error rate relative to the HCs group. Meanwhile, significantly increased executive control network efficiency suggested the dysfunction of inhibition control in PA patients. Regarding ERP results, there were no group differences in the alerting and orienting networks. The target-related P3 was significantly reduced in the PA group, suggesting an impairment of executive control function and attentional resources allocation. Moreover, the mean amplitude of P3 was significantly lateralized to the right hemisphere, and interacted with the visual field, exhibiting that the right hemisphere dominated the bilateral visual field, whereas the left hemisphere dominated the left visual field. In the specific high-conflict condition, the pattern of hemispheric asymmetry in the PA group was altered due to a mixed effect resulting from the compensatory recruitment of attentional resources in the left central parietal area and the destructive effects of hyperprolactinemia.

Conclusion

These findings suggested that, in the lateralized condition, the decreased P3 in the right central parietal area and the diminished hemispheric asymmetry under high conflict load, may serve as the potential biomarkers of attentional dysfunction in patients with pituitary adenoma.

Italian Association of Clinical Endocrinologists (AME) and International Chapter of Clinical Endocrinology (ICCE). Position statement for clinical practice: prolactin-secreting tumors

Prolactinomas are the most frequent pituitary adenomas. Prolactinoma may occur in different clinical settings and always require an individually tailored approach. This is the reason why a panel of Italian neuroendocrine experts was charged with the task to provide indications for the diagnostic and therapeutic approaches that can be easily applied in different contexts. The document provides 15 recommendations for diagnosis and 54 recommendations for treatment, issued according to the GRADE system. The level of agreement among panel members was formally evaluated by RAND-UCLA methodology. In the last century, prolactinomas represented the paradigm of pituitary tumors for which the development of highly effective drugs obtained the best results, allowing to avoid neurosurgery in most cases. The impressive improvement of neurosurgical endoscopic techniques allows a far better definition of the tumoral tissue during surgery and the remission of endocrine symptoms in many patients with pituitary tumors. Consequently, this refinement of neurosurgery is changing the therapeutic strategy in prolactinomas, allowing the definitive cure of some patients with permanent discontinuation of medical therapy.

Acromegaly in the elderly patient

Acromegaly is an insidious disease, usually resulting from growth hormone hypersecretion by a pituitary adenoma. It is most often diagnosed during the 3rd to 4th decade of life. However, recent studies have shown an increase in the incidence and prevalence of acromegaly in the elderly, probably due to increasing life expectancy. As in the younger population with acromegaly, there is a delay in diagnosis, aggravated by the similarities of the aging process with some of the characteristics of the disease. As can be expected elderly patients with acromegaly have a higher prevalence of comorbidities than younger ones. The diagnostic criteria are the same as for younger patients. Surgical treatment of the pituitary adenoma is the primary therapy of choice unless contraindicated. Somatostatin receptor ligands are generally effective as both primary and postoperative treatment. The prognosis correlates inversely with the patient's age, disease duration and last GH level. Arch Endocrinol Metab. 2019;63(6):638-45.

Radiotherapy as a tool for the treatment of Cushing's disease

Treatment of Cushing's disease (CD) is one of the most challenging tasks in endocrinology. The first-line treatment, transsphenoidal pituitary surgery, is associated with a high failure rate and a high prevalence of recurrence. Re-operation is associated with an even higher rate of a failure and recurrence. There are three main second-line treatments for CD - pituitary radiation therapy (RT), bilateral adrenalectomy and chronic cortisol-lowering medical treatment. All these treatments have their limitations. While bilateral adrenalectomy provides permanent cure of the hypercortisolism in all patients, the unavoidable chronic adrenal insufficiency and the risk of development of Nelson syndrome are of concern. Chronic cortisol-lowering medical treatment is not efficient in all patients and side effects are often a limiting factor. RT is efficient for approximately two-thirds of all patients with CD. However, the high prevalence of pituitary insufficiency is of concern as well as potential optic nerve damage, development of cerebrovascular disease and secondary brain tumours. Thus, when it comes to decide appropriate treatment for patients with CD, who have either failed to achieve remission with pituitary surgery, or patients with recurrence, the pros and cons of all second-line treatment options must be considered.