Long-term outcome of hypothalamic pituitary tumors in Langerhans cell histiocytosis

Hypothalamic-pituitary (HP) disease is the most common CNS manifestation of Langerhans cell histiocytosis (LCH) frequently leading to diabetes insipidus (DI) and anterior pituitary hormone deficiencies (APD). On MRI, loss of the normal posterior pituitary signal and thickening of the pituitary stalk have been described, as well as neurodegenerative signal changes associated with neuropsychological disabilities in some patients. The influence of therapy on the long-term course of HP tumors and neurodegeneration (ND) is not well-understood.

In this retrospective survey we focused on patients with LCH and HP disease with clinical and MRI data available at diagnosis of HP disease and at least three follow up investigations. We collected clinical and MRI follow-up information for central review and analysis.

We identified 22 patients with HP tumors (HPT) registered at the LCH study center. Many different treatment regimens were applied for variable periods, with more than one regimen in most patients. Regression of the tumor was seen in the majority, but all patients had APD or ND on MRI at last follow up. In none of the patients APD and ND regressed or resolved. A deterioration of radiological ND was noted in 17 patients leading to overt clinical neuropsychological impairment in five.

Patients with HPT appear to be at high risk to develop permanent neuroendocrine consequences. Coordinated studies for patients with LCH and HP disease including thorough MRI monitoring and neuropsychological tests are needed.