Coexistence of Essential Thrombocythemia and Pituitary Adenoma: A Case Report of a Saudi Female Patient

Abstract

Abstract: Essential thrombocythemia (ET) is a malignant hematological disease that has the ability to progress to acute leukemia or transform into other myeloproliferative neoplasms (MPNs). The coexistence of ET and other MPNs with pituitary adenoma (PA) is rare. There are no reports of cases of secretory PA of prolactin hormone in combination with ET. This case was reported in a young woman from Saudi Arabia who had the secretory PA present in combination with ET. The 20-year-old patient was treated for a micro-PA with hyperprolactinemia. The patient was referred to the hematological service for thrombocytosis. There was no history of thrombosis, cardiovascular risk factors, or constitutional symptoms. Laboratory tests showed that platelet levels consistently lagged from 700 × 103/µL to 1000 × 103/µL for 1 year. Hemoglobin 13 g/dL, white blood cells (WBCs) 6 × 103/µL, and normal WBC differential. The peripheral blood smear was inconclusive. A peripheral blood sample was sent for the cytogenetic study of myeloproliferative diseases, which came to be positive for c.1849G>T p.(V617F) mutation in the EXON 14 Janus kinase 2 (JAK2) gene. The patient was diagnosed with a MPN, ET with positive exon 14 JAK2, at low-risk category. Evidence suggests that MPNs in combination with endocrinological diseases are rare. However, there is a high incidence of MPN and unrelated tumors such as PA. Further research is recommended to thoroughly investigate endocrine tumors and look beyond secondary thrombocytosis that leads to thrombocythemia as in ET.