A 7-Gene Signature Depicts the Biochemical Profile of Early Prefibrotic Myelofibrosis.

Recent studies have shown that a large proportion of patients classified as essential thrombocythemia (ET) actually have early primary prefibrotic myelofibrosis (prePMF), which implies an inferior prognosis as compared to patients being diagnosed with so-called genuine or true ET. According to the World Health Organization (WHO) 2008 classification, bone marrow histology is a major component in the distinction between these disease entities. However, the differential diagnosis between them may be challenging and several studies have not been able to distinguish between them. Most lately, it has been argued that simple blood tests, including the leukocyte count and plasma lactate dehydrogenase (LDH) may be useful tools to separate genuine ET from prePMF, the latter disease entity more often being featured by anemia, leukocytosis and elevated LDH. Whole blood gene expression profiling was performed in 17 and 9 patients diagnosed with ET and PMF, respectively. Using elevated LDH obtained at the time of diagnosis as a marker of prePMF, a 7-gene signature was identified which correctly predicted the prePMF group with a sensitivity of 100% and a specificity of 89%. The 7 genes included MPO, CEACAM8, CRISP3, MS4A3, CEACAM6, HEMGN, and MMP8, which are genes known to be involved in inflammation, cell adhesion, differentiation and proliferation. Evaluation of bone marrow biopsies and the 7-gene signature showed a concordance rate of 71%, 79%, 62%, and 38%. Our 7-gene signature may be a useful tool to differentiate between genuine ET and prePMF but needs to be validated in a larger cohort of "ET" patients.

Hypogammaglobulinemia in newly diagnosed chronic lymphocytic leukemia is a predictor of early death.

Hypogammaglobulinemia is the most common immune deficiency in chronic lymphocytic leukemia (CLL). However, the prognostic significance in terms of morbidity and mortality remains controversial. We here evaluate the significance of hypogammaglobulinemia in terms of infections, treatment-free survival (TFS), and overall survival (OS). A total of 159 consecutive, newly diagnosed patients were included for analysis. Twenty-five patients (16%) had a moderate or severe infection within one year of diagnosis, but no associations were found between low immunoglobulin (Ig) levels and infections. In multivariate analysis, we found age (>65), high Binet stage, high ß2-microglobulin, and Ig deficiency to be associated with shorter OS. Decreased levels of IgM, deletion of chromosome 17p and unmutated IGHV status had independent negative impact on TFS. Thus, patients with hypogammaglobulinemia did not suffer more from infections early in the disease course, and decreased Ig had independent negative prognostic impact in CLL.

Minimal residual disease after long-term interferon-alpha2 treatment: a report on hematological, molecular and histomorphological response patterns in 10 patients with essential thrombocythemia and polycythemia vera.

Essential thrombocythemia (ET) and polycythemia vera (PV) are Philadelphia chromosome-negative chronic myeloproliferative neoplasms (MPNs) characterized by the JAK2 V617F mutation, which can be found in more than 98% of PV patients and in ∼ 50% of ET patients. Assessment of the JAK2 V617F allele burden by a highly sensitive quantitative PCR (qPCR) assay appears to be a useful tool for monitoring minimal residual disease (MRD) and evaluating treatment efficacy. This report expands and substantiates existing data, showing that IFN-alpha2 is a highly potent immunomodulating agent capable of inducing MRD with low-burden JAK2 V617F, major molecular response (MMR), complete hematological remission (CHR) and complete histomorphological normalization of the bone marrow in a sub-set of patients with ET and PV after long-term treatment (≥ 3.5 years). Furthermore, long-lasting hematological, molecular and histomorphological remissions are sustained after discontinuation of IFN-alpha2 for up to ∼ 5-6 years.

A highly sensitive quantitative real-time PCR assay for determination of mutant JAK2 exon 12 allele burden.

Mutations in the Janus kinase 2 (JAK2) gene have become an important identifier for the Philadelphia-chromosome negative chronic myeloproliferative neoplasms. In contrast to the JAK2V617F mutation, the large number of JAK2 exon 12 mutations has challenged the development of quantitative assays. We present a highly sensitive real-time quantitative PCR assay for determination of the mutant allele burden of JAK2 exon 12 mutations. In combination with high resolution melting analysis and sequencing the assay identified six patients carrying previously described JAK2 exon 12 mutations and one novel mutation. Two patients were homozygous with a high mutant allele burden, whereas one of the heterozygous patients had a very low mutant allele burden. The allele burden in the peripheral blood resembled that of the bone marrow, except for the patient with low allele burden. Myeloid and lymphoid cell populations were isolated by cell sorting and quantitative PCR revealed similar mutant allele burdens in CD16+ granulocytes and peripheral blood. The mutations were also detected in B-lymphocytes in half of the patients at a low allele burden. In conclusion, our highly sensitive assay provides an important tool for quantitative monitoring of the mutant allele burden and accordingly also for determining the impact of treatment with interferon-α-2, shown to induce molecular remission in JAK2V617F-positive patients, which may be a future treatment option for JAK2 exon 12-positive patients as well.

Intensive treatment and stem cell transplantation in chronic myelogenous leukemia: long-term follow-up.

In the present study we combined interferon (IFN) and hydroxyurea (HU) treatment, intensive chemotherapy and autologous stem cell transplantation (SCT) in newly diagnosed chronic myelogenous leukemia patients aged below 56 years, not eligible for allogeneic SCT. Patients who had an HLA-identical sibling donor and no contraindication went for an allogeneic SCT (related donor, RD). After diagnosis, patients not allotransplanted received HU and IFN to keep WBC and platelet counts low. After 6 months patients with Ph-positive cells still present in the bone marrow received 1-3 courses of intensive chemotherapy. Those who became Ph-negative after IFN + HU or after 1-3 chemotherapy courses underwent autologous SCT. Some patients with poor cytogenetic response were allotransplanted with an unrelated donor (URD). IFN + HU reduced the percentage of Ph-positive metaphases in 56% of patients, and 1 patient became Ph-negative. After one or two intensive cytotherapies 86 and 88% had a Ph reduction, and 34 and 40% became Ph-negative, respectively. In patients receiving a third intensive chemotherapy 92% achieved a Ph reduction and 8% became Ph-negative. The median survival after auto-SCT (n = 46) was 7.5 years. The chance of remaining Ph-negative for up to 10 years after autologous SCT was around 20%. The overall survival for allo-SCT RD (n = 91) and URD (n = 28) was almost the same, i.e. approximately 60% at 10 years. The median survival for all 251 patients registered was 8 years (historical controls 3.5 years). The role of the treatment schedule presented in the imatinib era is discussed.