Anorexia as an early sign of fourth ventricle hemangioblastoma: case-based literature review

Introduction: Brain tumors can be a known cause of reduction in food intake, thus mimicking anorexia nervosa, through various mechanisms. Hypothalamic lesions are the most commonly reported neural causes of anorexia-like syndrome, consisting in a diencephalic cachexia but without the typical psychopathology. Fourth ventricle tumors are a less common cause.

Case Report: We present a case of a teenager with a posterior fossa hemangioblastoma initially manifested as severe anorexia. The tumor was lately diagnosed when she started presenting headache and vomiting due to intracranial hypertension secondary to associated hydrocephalus. Patient underwent ventricular peritoneal shunt with improvement of the food intake afterwards.

Discussion: Many mechanisms have been associated to anorexia-like syndrome, such as direct brainstem compression, peptides secretion and hydrocephalus. The fact that BMI increased, and the children resumed normal food intake after hydrocephalus treatment suggests a non-lesional pattern. It is postulated that the physiopathology of hypothalamic dysfunction caused by the hydrocephalus is due to pathological pressure pulses in the third ventricle, which presents abnormal dilatation secondary to obstructive hidrocephalus, resulting in the absence of a GnRH pulse generator. Previous studies suggested a higher incidence of anorexia in hemangioblastomas. The proposed explanation was that these tumors frequently arise in the dorsal region of the brainstem and lead to direct compression of the floor of the fourth ventricle. Also, their slow growth due to their benign biological nature may account for their characteristic insidious progression with minimal neurologic deficits and diagnostic delay. Literature review revealed less then 30 cases of brainstem hemangioblastomas presenting with anorexia-like syndrome.

Conclusion: Unexplained or atypical anorexia, i.e. in the absence of weight concerns or body image disturbances, should prompt brain image. The lack of knowledge of this entity may lead to a late diagnosis and poor prognosis.