gms | German Medical Science

Objective: Hemangioblastomas are associated with elevated hemoglobin levels (polyglobulia). In older reports the incidence of polyglobulia was stated with up to 48% of all hemangioblastoma patients, whereas more recent reports assess the incidence much lower. Polyglobulia was considered to be the result of elevated serum erythropoietin (EPO) caused by secretion of the tumor or associated tumor cyst. This current study evaluates the relation between polyglobulia, EPO, solid tumor size and associated cystic formation in hemangioblastomas.

Method: We retrospectively investigated hemoglobin and EPO levels in a series of 33 consecutive patients operated for hemangioblastoma in our center. We measured the size of the solid tumor and associated tumor cyst in MRI. Two patients were excluded due to co-morbidities that potentially influence hemoglobin or EPO levels. Statistical evaluations were performed using the student’s t-test.

Results: Of all patients with elevated hemoglobin levels (5 patients, 16% of all patients) only one patient had an elevated EPO level. The other 4 patients all had normal levels. Patients with low or normal hemoglobin levels (84%) had an average tumor size of 0.9 cm³, which differed significantly from patients with elevated hemoglobin levels (16%), who had an average solid tumor size of 7.0 cm³ (p<0.0001). We did not observe a significant correlation between EPO levels or polyglobulia and associated cysts.

Conclusions: In contrast to previous case reports and interpretations, polyglobulia in patients with hemangioblastomas is not correlated with EPO levels or associated cysts. Moreover our data show that it is the size of the solid tumor that correlates with polyglobulia. The difference compared to higher incidences of polyglobulia in the past may be due to the fact, that hemangioblastomas are nowadays detected more frequently and operated at a smaller size than in the past.