Introduction: The coexistence of acromegaly and secondary polycythemia has been described in a few patients. This association was ascribed to GH/IGF1 proliferative effect on bone marrow progenitor cells. In contrast, the presence of myeloproliferative neoplasm (MPN) with documented JAK2 mutation so far has been described in only one acromegalic patient.
Methods: We analyzed the prevalence of MPN in patients with pituitary acromegaly in a retrospective study conducted on 100 consecutive acromegalic patients, admitted to the Centre between January 2003 and January 2013. Control group consisted of 408 consecutive patients with diabetes mellitus type 2 (DMT2) matched for age and sex, admitted in the same period.
Results: Three of 100 (3%) acromegalics and none of the patients with DMT2 had MPN (P<0.01). One patient was diagnosed with polycythemia vera (PV), one with essential thrombocythemia (ET) and one with primary myelofibrosis (MF). JAK2 V617F mutation was found in patients with PV and ET. In addition to pituitary tumor, patient with PV was diagnosed with primary hyperparathyroidism, but no mutation was found in MEN1 gene. Due to persistent hypersomatotropism after pituitary surgery, all patients with MPN were treated with somatostatin analogues. Carriers of JAK2 mutation required treatment with hydroxyurea.
Conclusion: These preliminary results suggest that patients with acromegaly might be at increased risk for development of MPN. Whether the excessive GH/IGF1 axis activity has promotive role in the pathogenesis of MPN needs to be further investigated.