Rafael Santana-Davila

Chromosome abnormalities clustering and its implications for pathogenesis and prognosis in myeloma

The nonrandom recurrent nature of chromosome abnormalities in myeloma suggests a role for them in disease pathogenesis. We performed a careful cytogenetic analysis of patients with abnormal karyotypes (n = 254), to discern patterns of association, search for novel abnormalities and elucidate clinical implications. Patients with karyotypic abnormalities suggestive of myelodysplasia/acute leukemia were excluded. In this study we compared survival by abnormality only between patients with abnormal karyotypes. Patients with abnormalities were more likely to have features of aggressive disease as compared to all other patients without abnormalities entered into the myeloma database (lower hemoglobin, higher β2-microglobulin, labeling-index and plasmocytosis; all P < 0.0001). Several groups of patients could be readily identified; hypodiploid (22%), pseudodiploid (36%), hyperdiploid (31%) and near-tetraploid (11%). Clustering associations were seen among several trisomies and monosomy of chromosome 13 and 14. Several monosomies (−2, −3, −13, −14 and −19), 1p translocations/ deletions, and hypodiploidy were associated with a significantly shorter survival. Trisomy of chromosome 13 was rare (<2%). Even among patients with abnormal karyotypes, specific chromosome abnormalities can impart biologic variability in myeloma, including several monosomies, hypodiploidy and abnormalities of 1p.

Prognostic factors for hyperdiploid-myeloma: effects of chromosome 13 deletions and IgH translocations

Chromosomal hyperdiploidy is the defining genetic signature in 40–50% of myeloma (MM) patients. We characterize hyperdiploid-MM (H-MM) in terms of its clinical and prognostic features in a cohort of 220 H-MM patients entered into clinical trials. Hyperdiploid-myeloma is associated with male sex, kappa immunoglobulin subtype, symptomatic bone disease and better survival compared to nonhyperdiploid-MM (median overall survival 48 vs 35 months, log-rank P=0.023), despite similar response to treatment. Among 108 H-MM cases with FISH studies for common genetic abnormalities, survival is negatively affected by the existence of immunoglobulin heavy chain (IgH) translocations, especially those involving unknown partners, while the presence of chromosome 13 deletion by FISH did not significantly affect survival (median overall survival 50 vs 47 months, log-rank P=0.47). Hyperdiploid-myeloma is therefore a unique genetic subtype of MM associated with improved outcome with distinct clinical features. The existence of IgH translocations but not chromosome 13 deletion by FISH negatively impacts survival and may allow further risk stratification of this population of MM patients.

Rearrangements and amplification of IER3 (IEX-1) represent a novel and recurrent molecular abnormality in myelodysplastic syndromes

IER3 (formerly IEX-1) encodes a 27-kDa glycoprotein that regulates death receptor-induced apoptosis, interacts with NF-kappaB pathways, and increases expression rapidly in response to cellular stresses such as irradiation. Animal models, gene expression microarray experiments, and functional studies in cell lines have suggested a potential role for IER3 in oncogenesis, but, to date, no abnormalities of IER3 at the DNA level have been reported in patients with neoplasia. Here, we describe breakpoint cloning of a t(6;9)(p21;q34) translocation from a patient with a myelodysplastic syndrome (MDS), facilitated by conversion technology and array-based comparative genomic hybridization, which revealed a rearrangement translocating the IER3 coding region away from critical flanking/regulatory elements and to a transcript-poor chromosomal region, markedly decreasing expression. Using split-signal and locus-specific fluorescence in situ hybridization (FISH) probes, we analyzed 204 patients with diverse hematological malignancies accompanied by clonal chromosome 6p21 abnormalities, and found 8 additional patients with MDS with IER3 rearrangements (translocations or amplification). Although FISH studies on 157 additional samples from patients with MDS and a normal-karyotype were unrevealing, and sequencing the IER3 coding and proximal promoter regions of 74 MDS patients disclosed no point mutations, reverse transcription-PCR results suggested that dysregulated expression of IER3 is common in MDS (61% >4-fold increase or decrease in expression with decreased expression primarily in early MDS and increased expression primarily in later MDS progressing toward leukemia), consistent with findings in previous microarray experiments. These data support involvement of IER3 in the pathobiology of MDS.

Myelodysplastic syndromes associated with interstitial deletion of chromosome 5q: Clinicopathologic correlations and new insights from the prelenalidomide era

To better estimate prognosis for patients with myelodysplastic syndromes (MDS) associated with clonal interstitial deletions of the long arm of chromosome 5 (del(5q)), we reviewed the medical records of 130 adults with del(5q) MDS seen at our institution over a 15‐year period. Overall median survival of this cohort was 9.5 months, shorter than reported in earlier series. The least favorable outcomes are associated with complex cytogenetics, lack of any normal metaphases, normocytic rather than macrocytic erythrocyte indices, and low baseline lymphocyte counts. Lymphopenia but not neutropenia at the time of diagnosis appears to be a new adverse prognostic indicator. Cytogenetic breakpoints defined by G‐banded karyotyping correlate poorly with particular disease features. Surprisingly, survival of patients with treatment‐related MDS was equivalent to that of de novo MDS with del(5q) in this series. Morphologic features associated with del(5q) are diverse. Most patients with del(5q) MDS do not meet criteria for WHO‐defined 5q‐syndrome, and the presence of del(5q) does not appear to modify the clinical phenotype otherwise risk‐stratified by the International Prognostic Scoring System (IPSS). Additional important prognostic factors not taken into account by the IPSS include the baseline erythrocyte indices, lymphocyte count, and clonal burden. Am. J. Hematol., 2008.

Primary myelofibrosis is the most frequent myeloproliferative neoplasm associated with del(5q): Clinicopathologic comparison of del(5q)-positive and -negative cases

Among 23 cases of myeloproliferative neoplasms (MPNs) with an associated del(5q) seen at our institution, 14 (61%) fulfilled diagnostic criteria for primary myelofibrosis (PMF). Other diagnoses included polycythemia vera (PV; n=2), essential thrombocythemia (ET; n=1), post-ET myelofibrosis (n=1), systemic mastocytosis (SM; n=1), and MPN, unclassifiable (n=4). Compared to their del(5q)-negative counterparts, del(5q)-positive PMF cases were significantly more anemic (p<0.001) and thrombocytopenic (p<0.001). However, survival and leukemic transformation rates appear to be similar between the two groups. del(5q)-positive PMF was histologically characterized by a mixture of both small and monolobated megakaryocytes as well as large and bizarre megakaryocytes. When used, lenalidomide therapy induced hematological and cytogenetic remissions in del(5q)-positive PMF. The current study identifies PMF as another del(5q)-associated myeloid malignancy with characteristic megakaryocyte morphology.

Capecitabine and Temozolomide: Design, Implementation, and Preliminary Outcomes From a Pilot Project to Ensure Safe Prescribing of Oral Chemotherapy

Without adequate safety measures, oral chemotherapy can lead to undetected dosing errors. The Mayo Clinic launched a project to ensure that all capecitabine and temozolomide prescriptions receive an independent double check.

Dysgranulopoiesis is an independent adverse prognostic factor in chronic myeloid disorders with an isolated interstitial deletion of chromosome 5q

Dysgranulopoiesis is an independent adverse prognostic factor in chronic myeloid disorders with an isolated interstitial deletion of chromosome 5q