Objective: The objective of the study was to analyze the contemporary clinical and laboratory features of polycythemia vera (PV), as well as to evaluate the short- and long-term results of different treatment options.
Methodology: The clinico-hematological evolution features, complications, short- and long-term results of cytoreductive treatment were evaluated in a group of 114 PV patients, aged at 28–78 years old, who were followed up at the Institute of Oncology of Moldova between 1987–2019. The diagnosis was proved by the bone marrow biopsy and quantitative detection of JAK2 V617F mutation in pending cases. Physical and histopathologic examinations were associated with the repeated complete blood counts and abdominal ultrasound scan. The treatment included phlebotomies and cytoreductive chemotherapy with busulfan (56 patients) and hydroxycarbamide (58 patients) in standard doses. The life-table method was used for Kaplan–Meier Survival Analysis in order to evaluate the long-term results of treatment.
Results: The disease was commonly diagnosed in males – 66 (57.9%) patients. The females prevailed in the age groups of 40–49 years (31.3% versus 24.6% in males) and 60–69 years (25% versus 19.8% in males). The disease span from the onset of the initial clinical manifestations until the diagnosis lasted 4–9 months (median – 5.8 months) in the majority of patients (86.8%), that led to the development of thromboembolic complications in 28.1% of cases. The diagnosis was proved in stage IIA disease in 105 (92.1%) patients, IIB in 9 (7.9%) patients. The skin hiperemia was registered in 112 (98.3%) cases, scleral congestion – in 109 (95.6%), splenomegaly – in 77 (67.5%), erythromelalgia – in 71 (62.2%), aquagenic skin itching – in 68 (59.6%), hepatomegaly – in 61 (53.5%), vascular thrombosis – in 32 (28.1%). The complete blood count revealed the increase of hemoglobin (18.0–23.5g/dL) and red cells (5.5–6.7×1,000,000 [MICRO]/L). The platelets range was 180–1690×1000 [MICRO]/L, leukocytes range – 5.1–21.3×1000 [MICRO]/L. Leukocytosis occurred in 69 (60.5%) patients, thrombcytosis – in 61 (53.5%). The bone marrow biopsy detected a hyperplasia due to the proliferation of erythroid, granulocyte and megakaryocyte cell lines. The study of short-term results asserted the complete remissions in all cases under chemotherapy combined with phlebotomies. The overall one-, 5-, 10- and 15 year was 100%, 98.6%, 85.9% and 67.1%, respectively. 73 (64.04%) patients remain in stage II disease after the treatment during 5–26 years of follow-up. The survival median was not reached.
Conclusion: The reluctant evolution, progressive growth of hemoglobin and red cell count, gradual increase of blood hyperviscosity and the lack of hemato-oncological vigilance of primary care physicians may lead to the development of thrombotic and vascular complications in some PV cases. Chemotherapy improves significantly the patient's quality of life, reduces the rate of thromboembolic events and extends the life-span, comparable with that of total population of Moldova.
