JAK2 mutation: an aid in the diagnosis of occult myeloproliferative neoplasms in patients with major intraabdominal vein thrombosis and normal blood counts.

BACKGROUND: Janus kinase-2 (JAK2) is mutated in a high proportion of patients with polycythemia vera and in a smaller number with essential thrombocythemia and primary myelofibrosis. Mutated JAK2 is an important diagnostic marker for myeloproliferative neoplasm (MPN) and may also play a major role in the pathogenesis of MPN. OBJECTIVES: To evaluate the prevalence of mutated JAK2 (JAK2-V617F) among patients with major intraabdominal vein thrombosis who had normal blood counts at diagnosis of the initial event. METHODS: The medical records of patients who presented with a major intraabdominal venous thrombosis and normal peripheral blood counts were obtained. JAK2-V617F mutation status was determined by real-time polymerase chain reaction. RESULTS: Twenty-two patients were available for this analysis and 9 (41%) were found to have JAK2-V617F. Patients with positive JAK2-V617F were younger and had more frequent clinical splenomegaly than those with wild-type JAK2. CONCLUSIONS: A high proportion of patients presenting with "idiopathic" major intraabdominal vein thrombosis and normal blood counts carry JAK2-V617F. We recommend searching for the mutation in this clinical setting to detect patients with occult MPN.

Total and differential leukocyte counts percentiles in normal pregnancy.

OBJECTIVE: To establish leukocyte count and leukocyte differential percentiles in normal uncomplicated pregnancy. STUDY DESIGN: This retrospective longitudinal study was performed in an outpatient facility for routine antenatal care. The study population comprised of 726 healthy women from the 5th to the 41st week of pregnancy. Altogether, there were 1749 complete blood count evaluations, of which 481 were in the 1st trimester, 687 in the 2nd trimester and 581 in the 3rd trimester. The total and differential leukocyte counts were determined by an automated cell counter. RESULTS: The leukocyte and neutrophil counts gradually and significantly increased form the 1st to the 3rd trimester. The monocyte count increase became significant only during the 3rd trimester. The eosinophil count did not significantly change throughout pregnancy. The basophil count significantly decreased during the 2nd trimester and returned to 1st trimester values during the 3rd trimester. CONCLUSION: In this study, we provide total and differential leukocyte counts' mean+/-S.D., minimal and maximal values, and the 3rd, 5th, 10th, 50th, 90th, 95th, and 99th percentiles for entire pregnancy and for each trimester separately. These reference values should prove useful for diagnostic and research purposes.

High response rate for treatment with gemtuzumab ozogamicin and cytarabine in elderly patients with acute myeloid leukemia and favorable and intermediate-I cytogenetic risk.

UNLABELLED: Recent studies have reevaluated whether gemtuzumab ozogamicin (GO) improves the outcome of acute myeloid leukemia (AML) in elderly patients. Over 5 years, we treated 16 elderly patients with AML with GO and cytarabine. A high response rate, prolonged survival, and low toxicity were observed in the favorable and intermediate-I genetic groups of AML. Our study raises the issue about the optimal protocol for these patients. BACKGROUND: The benefit of gemtuzumab ozogamicin (GO) in combination with chemotherapy as frontline therapy in patients with acute myeloid leukemia (AML) is still debated. PATIENTS AND METHODS: We evaluated the safety and efficacy of low-dose GO with cytarabine in elderly patients with newly diagnosed AML. Over the past 5 years, we have treated 16 elderly patients with AML (64-82 years) with GO (3 mg/m(2)) followed by continuous infusion of cytarabine (100 mg/m(2)) for 7 days. RESULTS: Complete remission (CR) was achieved in 68.8% of patients; however, this was true only in patients in the favorable or intermediate-I cytogenetic risk groups. Of the 12 patients with AML in the favorable and intermediate-I genetic groups, 11 (91.7%) achieved CR. By comparison, of all 4 patients in the intermediate-II or adverse genetic groups, none of the patients achieved CR (P = .003). The median disease-free survival and overall survival (OS) was 10.9 and 18.8 months, respectively, for patients who achieved CR. The estimated median survival was 15 months in the favorable and intermediate-I cytogenetic groups and only 4.4 months in the intermediate-II and unfavorable risk groups (P = .008). The toxicity profile was also manageable in patients with AML who were mainly older than 70 years with good performance status (PS). The 8-week mortality rate was 6.25%, which is relatively low in this high-risk group of patients. These data are in line with results from 2 randomized trials suggesting that the addition of low-dose GO should be further investigated to reevaluate its role in selected elderly patients with AML and raises the issue of the optimal protocol.