Risk stratification for survival and leukemic transformation in essential thrombocythemia: a single institutional study of 605 patients.

Unlike the case with thrombosis, prognostic models for survival and leukemic transformation (LT) in essential thrombocythemia (ET) are not available. Among 605 patients with ET seen at our institution and followed for a median of 84 months, 155 died and LT was documented in 20 patients (3.3%). In a multivariable analysis, hemoglobin level below normal (females<120 g/l; males<135 g/l) was identified as an independent risk factor for both inferior survival and LT. Additional risk factors for survival included age > or =60 years, leukocyte count> or =15 x 10(9)/l, smoking, diabetes mellitus and thrombosis. For LT, platelet count> or =1000 x 10(9)/l but not cytoreductive therapy was flagged as an additional independent risk factor. In fact, four of the 20 patients (20%) with LT were untreated previously. We used the above information to construct prognostic models that effectively discriminated among low-, intermediate- and high-risk groups with respective median survivals of 278, 200 and 111 months (P<0.0001), and LT rates of 0.4, 4.8 and 6.5% (P=0.0009) respectively. Presence of JAK2V617F did not impact either survival or LT and mutational frequency was similar among the different risk groups.

Novel FISH probes designed to detect IGK-MYC and IGL-MYC rearrangements in B-cell lineage malignancy identify a new breakpoint cluster region designated BVR2.

Detection of translocations involving MYC at 8q24.1 in B-cell lineage malignancies (BCL) is important for diagnostic and prognostic purposes. However, routine detection of MYC translocations is often hampered by the wide variation in breakpoint location within the MYC region, particularly when a gene other than IGH, such as IGK or IGL, is involved. To address this issue, we developed and validated four fluorescence in situ hybridization (FISH) probes: two break apart probes to detect IGK and IGL translocations, and two dual-color, dual-fusion FISH (D-FISH) probes to detect IGK-MYC and IGL-MYC. MYC rearrangements (four IGK-MYC, 12 IGL-MYC and four unknown partner gene-MYC) were correctly identified in 20 of 20 archival BCL specimens known to have MYC rearrangements not involving IGH. Seven specimens, all of which lacked MYC rearrangements using a commercial IGH/MYC D-FISH probe, were found to have 8q24 breakpoints within a cluster region >350-645 kb 3' from MYC, provisionally designated as Burkitt variant rearrangement region 2 (BVR2). FISH is a useful ancillary tool in identifying MYC rearrangements. In light of the discovery of the distally located BVR2 breakpoint cluster region, it is important to use MYC FISH probes that cover a breakpoint region at least 1.0 Mb 3' of MYC.

Janus kinase 2 (V617F) mutation status, signal transducer and activator of transcription-3 phosphorylation and impaired neutrophil apoptosis in myelofibrosis with myeloid metaplasia.

An activating point mutation in Janus kinase 2 (JAK2 V617F) was recently identified in myelofibrosis with myeloid metaplasia (MMM). To further elucidate the pathogenic significance, we examined the JAK2 mutation burden, phosphorylation of JAK2 substrates and neutrophil apoptotic resistance. Immunoblotting revealed phosphorylation of signal transducer and activator of transcription-3 (STAT3) in all four JAK2 with high V617F mutant allele burden and seven of eight with intermediate mutant allele burden, but only one of eight with wild-type JAK2 (P<0.001). In contrast, STAT5 phosphorylation was undetectable in patient MMM neutrophils; and phosphorylation of Akt and extracellular signal-regulated kinases (ERKs) failed to correlate with JAK2 mutation status. Apoptosis was lower in MMM neutrophils (median 41% apoptotic cells, n=50) compared to controls (median 66%, n=9) or other myeloproliferative disorder patients (median 53%, n=11; P=0.002). Apoptotic resistance in MMM correlated with anemia (P=0.01) and the JAK2-V617F (P=0.01). Indeed, apoptotic resistance was greatest in MMM neutrophils with high mutant allele burden (median 22% apoptosis, n=5) than with intermediate burden (median 39%, n=23) or wild-type JAK2 (median 47%, n=22; P=0.008). These results suggest that mutant JAK2 contributes to MMM pathogenesis by constitutively phosphorylating STAT3 and diminishing myeloid cell apoptosis.

JAK2 V617F is a rare finding in de novo acute myeloid leukemia, but STAT3 activation is common and remains unexplained.

Signal transducer and activator of transcription (STAT) proteins are phosphorylated and activated by Janus kinases (JAKs). Recently, several groups identified a recurrent somatic point mutation constitutively activating the hematopoietic growth factor receptor-associated JAK2 tyrosine kinase in diverse chronic myeloid disorders - most commonly classic myeloproliferative disorders (MPD), especially polycythemia vera. We hypothesized that the JAK2 V617F mutation might also be present in samples from patients with acute myeloid leukemia (AML), especially erythroleukemia (AML-M6) or megakaryoblastic leukemia (AML-M7), where it might mimic erythropoietin or thrombopoietin signaling. First, we documented STAT3 activation by immunoblotting in AML-M6 and other AML subtypes. Immunoperoxidase staining confirmed phosphorylated STAT3 in malignant myeloblasts (21% of cases, including all AML-M3 samples tested). We then analyzed genomic DNA from 162 AML, 30 B-cell lymphoma, and 10 chronic lymphocytic leukemia (CLL) samples for JAK2 mutations, and assayed a subset for SOCS1 and FLT3 mutations. Janus kinase2 V617F was present in 13/162 AML samples (8%): 10/13 transformed MPD, and three apparent de novo AML (one of 12 AML-M6, one of 24 AML-M7, and one AML-M2 - all mixed clonality). FLT3 mutations were present in 5/32 (16%), while SOCS1 mutations were totally absent. Lymphoproliferative disorder samples were both JAK2 and SOCS1 wild type. Thus, while JAK2 V617F is uncommon in de novo AML and probably does not occur in lymphoid malignancy, unexplained STAT3 activation is common in AML. Janus kinase2 extrinsic regulators and other proteins in the JAK-STAT pathway should be interrogated to explain frequent STAT activation in AML.

Serous borderline tumor of the paratestis: a report of seven cases.

We report the clinical, morphologic, immunophenotypic, and ploidy findings of seven cases of serous borderline tumor of the paratestis. Mean patient age was 56 years (range, 14-77 years), and the clinical presentation was that of a testicular mass. Tumors ranged in size from 1 to 6 cm (mean, 3.5 cm). Six tumors arose from the tunica albuginea, and two of these tumors were intratesticular. One tumor arose from the tunica vaginalis. Serous borderline tumor of the paratestis is histologically identical to its ovarian counterpart. The tumors were cystic with numerous intracystic blunt papillae lined by stratified epithelial cells with minimal to mild cytologic atypia. Psammoma bodies were present in two cases. In all cases, the neoplastic cells stained strongly and diffusely for cytokeratin 7, estrogen receptor, and CD15, and six of seven cases were positive for progesterone receptor and MOC-31. The cells did not stain for cytokeratin 20, carcinoembryonic antigen, calretinin, and HER2/neu. Proliferative activity, as assessed by MIB-1 staining, ranged from 1.3% to 10% (mean, 5.5%). Five of six tumors were diploid, and one was tetraploid. Patients were treated by radical orchiectomy and followed up from 4 months to 18 years (mean, 48 months; median, 8.5 months). No recurrences or metastases occurred. Serous borderline tumor of the paratestis is morphologically and immunophenotypically identical to ovarian serous borderline tumor. To date, no serous borderline tumor of the paratestis reported in the literature or in our series has recurred or metastasized after resection.

Use of multiple displacement amplification to amplify genomic DNA before sequencing of the alpha and beta haemoglobin genes.

AIMS: To evaluate the technique of multiple displacement amplification (MDA) for whole genome amplification from small volume blood samples before sequencing in a clinical test to identify haemoglobin gene mutations. METHODS: Phage phi29 DNA polymerase was used to perform MDA, starting with either 1 micro l of blood or 1 ng of previously isolated blood DNA from 23 patients. The amplified products were then evaluated using a clinical test that involves sequencing the haemoglobin genes to detect mutations. The results were compared with the current clinical test method that uses genomic DNA isolated using column based technology. RESULTS: The MDA technique produced large quantities (theoretically approximately 2 mg) of DNA. The amplification procedure was extremely easy and took about four hours (less than one hour of hands on technician time and three hours for amplification). When MDA products were used in the same clinical test protocol as genomic DNA isolated using column technology, there was 100% concordance for detection of a variety of point mutations in the alpha1, alpha2, and beta globin genes. CONCLUSIONS: The MDA technique is useful for overcoming the problem of insufficient genomic DNA in clinical specimens requiring haemoglobin gene sequencing and could be useful for other clinical applications.

Do students studying therapy have more problems?

This study examined several questions on whether graduate students studying therapy reported more personal counseling or traumas than other students. The 66 students studying therapy did not report significantly different experiences or attitudes than 52 students in other areas, indicating that they did not seem to have more emotional problems or traumas than others.

Instructive case report. A 26-year-old Indian woman with seizures and multiple intracranial mass lesions.

We describe the case of a 26-year-old Indian woman who presented to our institution with seizures and papilledema. Her diagnosis was originally thought to be neurocysticercosis, but later confirmed to be intracranial tuberculoma. Antituberculous therapy with isoniazid, rifampin, pyrazinamide and ethambutol was initiated. Improvement in the patient's neurological symptoms with diminution in size of the intracerebral lesions was observed. This case illustrates the difficulty in distinguishing intracranial tuberculoma from neurocysticercosis. Radiological features that distinguish these two diseases are described. Both diseases must be considered in regions endemic for tuberculosis and cysticercosis.

IDH mutations in primary myelofibrosis predict leukemic transformation and shortened survival: clinical evidence for leukemogenic collaboration with JAK2V617F.

Isocitrate dehydrogenase (IDH) mutations are frequent in blast-phase myeloproliferative neoplasms and might therefore contribute to leukemic transformation. We examined this possibility in 301 consecutive patients with chronic-phase primary myelofibrosis (PMF). The mutant IDH was detected in 12 patients (4%): 7 IDH2 (5 R140Q, 1 R140W and 1 R172G) and 5 IDH1 (3 R132S and 2 R132C). In all, 6 (50%) of the 12 IDH-mutated patients also expressed JAK2V617F. Overall, 18 (6%) patients displayed only MPL and 164 (54.3%) only JAK2 mutations. Multivariable analysis that accounted for conventional risk factors disclosed inferior overall survival (OS; P=0.03) and leukemia-free survival (LFS; P=0.003) in IDH-mutated patients: OS hazard ratio (HR) was 0.39 (95% confidence interval (95% CI) 0.2-0.75), 0.50 (95% CI 0.27-0.95) and 0.53 (95% CI 0.23-1.2) for patients with no, JAK2 or MPL mutations, respectively. Further analysis disclosed a more pronounced effect for the mutant IDH on OS and LFS in the presence (P=0.0002 and P<0.0001, respectively) as opposed to the absence (P=0.34 and P=0.64) of concomitant JAK2V617F. Analysis of paired samples obtained during chronic- and blast-phase disease revealed the presence of both IDH and JAK2 mutations at both time points. Our observations suggest that IDH mutations in PMF are independent predictors of leukemic transformation and raise the possibility of leukemogenic collaboration with JAK2V617F.

A phase-2 trial of low-dose pomalidomide in myelofibrosis.

In a previous study, we reported on the safety and efficacy of low-dose (0.5 mg) pomalidomide and prednisone and pomalidomide alone (2 mg/day), for the treatment of anemia associated with myelofibrosis (MF). The current study examined the value of low-dose pomalidomide alone. The main eligibility criterion was transfusion-dependency or hemoglobin <10 gm per 100 ml. Anemia response was assessed by International Working Group criteria. Pomalidomide (0.5 mg/day) was given to 58 patients (median age 68 years); 46 (79%) were transfusion-dependent and 42 were JAK2V617F positive. Anemia response was documented only in the presence of JAK2V617F (24 vs 0%; P=0.03) but was not further affected by mutant allele burden (P=0.39); 9 of the 10 anemia responders became transfusion independent. Anemia response in JAK2V617F-positive patients was predicted by the presence of pomalidomide-induced basophilia in the first month of therapy (38 vs 6%; P=0.02) or absence of marked splenomegaly (38 vs 11%; P=0.05). A total of 14 (58%) of 24 patients with a platelet count of ≤ 100 × 10(9) cells/l experienced a >50% increment in platelet count. There were no spleen responses. Grade 3 or 4 thrombocytopenia/neutropenia occurred in 2%/0% of patients. Low-dose pomalidomide is effective in the treatment of anemia associated with JAK2V617F-positive MF; response is predicted by early drug-induced basophilia.

IDH1 and IDH2 mutation analysis in chronic- and blast-phase myeloproliferative neoplasms.

Bone marrow DNA was screened for isocitrate dehydrogenase (IDH) mutations in 200 patients with chronic (n=166) or blast (n=34) phase myeloproliferative neoplasms (MPN). Included among the former were 77 patients with primary myelofibrosis (PMF), 47 essential thrombocythemia and 38 polycythemia vera (PV). Nine IDH mutations (5 IDH1 and 4 IDH2) were detected; mutational frequencies were approximately 21% (7 of 34) for blast-phase MPN and approximately 4% (3 of 77) for PMF. IDH mutations were seen in only 1 of 12 paired chronic-blast-phase samples and in none of 27 concurrently studied acute myeloid leukemia (AML) patients without antecedent MPN. IDH1 mutations included R132C (n=4; two post-PMF AML, one post-PV AML and one PMF) and R132S (n=1; post-PMF AML). IDH2 mutations included R140Q (n=3; one post-PMF AML, one post-PV AML and one PMF) and a novel R140W (n=1; mutation found in both chronic- and blast-phase samples). The entire study cohort was also screened for JAK2 and MPL mutations and JAK2V617F was found in three IDH-mutated cases (two PMF and one PV). This study shows a relatively high incidence of IDH mutations in blast-phase MPN, regardless of JAK2 mutational status, and the occurrence of similar mutations in chronic-phase PMF.

IDH1 and IDH2 mutation studies in 1473 patients with chronic-, fibrotic- or blast-phase essential thrombocythemia, polycythemia vera or myelofibrosis.

In a multi-institutional collaborative project, 1473 patients with myeloproliferative neoplasms (MPN) were screened for isocitrate dehydrogenase 1 (IDH1)/IDH2 mutations: 594 essential thrombocythemia (ET), 421 polycythemia vera (PV), 312 primary myelofibrosis (PMF), 95 post-PV/ET MF and 51 blast-phase MPN. A total of 38 IDH mutations (18 IDH1-R132, 19 IDH2-R140 and 1 IDH2-R172) were detected: 5 (0.8%) ET, 8 (1.9%) PV, 13 (4.2%) PMF, 1 (1%) post-PV/ET MF and 11 (21.6%) blast-phase MPN (P<0.01). Mutant IDH was documented in the presence or absence of JAK2, MPL and TET2 mutations, with similar mutational frequencies. However, IDH-mutated patients were more likely to be nullizygous for JAK2 46/1 haplotype, especially in PMF (P=0.04), and less likely to display complex karyotype, in blast-phase disease (P<0.01). In chronic-phase PMF, JAK2 46/1 haplotype nullizygosity (P<0.01; hazard ratio (HR) 2.9, 95% confidence interval (CI) 1.7-5.2), but not IDH mutational status (P=0.55; HR 1.3, 95% CI 0.5-3.4), had an adverse effect on survival. This was confirmed by multivariable analysis. In contrast, in both blast-phase PMF (P=0.04) and blast-phase MPN (P=0.01), the presence of an IDH mutation predicted worse survival. The current study clarifies disease- and stage-specific IDH mutation incidence and prognostic relevance in MPN and provides additional evidence for the biological effect of distinct JAK2 haplotypes.