Faculty Bibliography

The combination of bortezomib (velcade), pulsed dexamethasone and weekly cyclophosphamide (CVD) in relapsed/refractory myeloma patients induces high overall (75%) and complete (31%) response rates compared to velcade/dexamethasone (overall 47%, CR 5%) and velcade alone (overall 27%, CR 0%). The toxicity profiles including thrombocytopenia, neutropenia, and neuropathy were comparable between the groups.

PURPOSE/OBJECTIVE:To compare the effects of pegylated interferon-alpha2b (P-IFN) and interferon-alpha2b (IFN) on quality of life (QoL) and toxicity in patients with multiple myeloma maintained on a steady dose of IFN. PATIENTS AND METHODS/METHODS:Consenting, eligible myeloma patients on IFN maintenance therapy for at least 6 weeks were randomly (1:1) allocated to receive P-IFN for 3 months followed by IFN for 3 months, or to continue with IFN for 3 months followed by P-IFN for 3 months (cross-over design). Patients were assessed for toxicity and QoL. Dose of P-IFN was equivalent to IFN. RESULTS:The study enrolled 60 patients. At enrollment, 35 patients were in complete remission, 20 in partial remission and 5 were minimal responders. P-IFN was associated with significantly better global QoL score (mean difference 8.4; P = 0.0002). There was a significant improvement in functional scales--physical (P = 0.03), emotional (P = 0.04), social (P = 0.0008) with P-IFN. Fatigue (P = 0.0003), pain (P = 0.02) and appetite loss (P = 0.003) symptom scales were less in patients while on P-IFN. There were no statistically significant differences between treatment arms in QoL as measured by QLQ-MY24. CONCLUSION/CONCLUSIONS:These data suggest that patients on P-IFN have a better QoL. Dose escalation studies are warranted to investigate potential impact on survival.

Veno-occlusive disease (VOD) is a common and high-risk complication of allogeneic stem cell transplantation (SCT). Defibrotide has recently been used successfully to treat the disorder. We report on 58 patients who received defibrotide prophylaxis without concurrent heparin. No patients fulfilled the Baltimore criteria for VOD or died of the condition within 100 days of SCT. None of this group developed haemorrhagic complications secondary to defibrotide. These observations suggest that prophylaxis with defibrotide alone may reduce the incidence of VOD post-SCT although a randomised controlled trial is warranted to further evaluate its role.

A greater understanding of the biology of myeloma has focused research on the identification of novel target-based treatment strategies. Proteasome inhibition represents one such approach and the introduction of bortezomib, the first-in-class proteasome inhibitor, has been a major breakthrough in the treatment of multiple myeloma. As a result of its novel mechanism of action, bortezomib has been shown to induce responses in patients previously refractory to treatment, and results in increased progression-free and overall survival rates. The current understanding of the biology of the proteasome and the mechanism by which proteasome inhibition leads to myeloma cell death is described in this review. The role of proteasome inhibitors in the management of myeloma is also discussed.

Inferring haplotypes from genotype data is commonly undertaken in population genetic association studies. Within such studies the importance of accounting for uncertainty in the inference of haplotypes is well recognised. We investigate the effectiveness of correcting for uncertainty using simple methods based on the output provided by the PHASE haplotype inference methodology. In case-control analyses investigating non-Hodgkin lymphoma and haplotypes associated with immune regulation we find little effect of making adjustment for uncertainty in inferred haplotypes. Using simulation we introduce a higher degree of haplotype uncertainty than was present in our study data. The simulation represents two genetic loci, physically close on a chromosome, forming haplotypes. Considering a range of allele frequencies, degrees of linkage between the loci, and frequency of missing genotype data, we detail the characteristics of genetic regions which may be susceptible to the influence of haplotype uncertainty. Within our evaluation we find that bias is avoided by considering haplotype probabilities or using multiple imputation, provided that for each of these methods haplotypes are inferred separately for case and control populations; furthermore using multiple imputation provides the facility to incorporate haplotype uncertainty in the estimation of confidence intervals. We discuss the implications of our findings within the context of the complexity of haplotype inference for larger marker rich regions as would typically be encountered in genetic analyses.

The aim of the study was to evaluate whether adequate stem cells (CD34+) could be harvested at presentation in myeloma patients such that high dose melphalan (HDM) with autologous stem cell rescue can be offered as primary therapy. The regimes either involved no prior cytoreductive chemotherapy (steroids only, n = 31) or a single course of VAD (n = 22). The median number of CD34 cells collected with steroids was 1.3 x 10(6) (0.2-5.6) compared to 4.6 x 10(6) (0.3-19.2) cells/kg with VAD (P < 0.0001). We conclude that it is possible to collect stem cells from myeloma patients at presentation with minimal prior therapy. Using this strategy, of a single prior course of chemotherapy followed by immediate harvest, it is feasible to offer early high-dose therapy in clinical situations where this is important.

Increased long-term survival seen in patients with solid and hematologic cancers achieved as a result of aggressive chemoradiotherapy has come at a price. Therapy-related acute myeloid leukemia has been frequently documented in these patient cohorts, and its biology well studied. Recognition of secondary non-Hodgkin lymphoma as a cause of significant morbidity and mortality in these patients is equally important. The patterns of incidence and latency of secondary lymphomas is distinct from that of myeloid malignancies and other solid cancers. We have systematically analyzed and summarized reports from various groups over the last three decades. Risk of secondary lymphomas increases after the first 5 years of completion of chemotherapy or radiotherapy and persists for more than three decades. This reinforces the need for long-term follow-up of all patients exposed to chemoradiotherapy and confirms that chemotherapeutic agents can cause lymphoma.

Polymorphisms in NFKBIA may be important in pre-disposition to and outcome after treatment, of multiple myeloma (MM). The NFKBIA gene product, IkappaBalpha, binds to NF-kappaB preventing its activation and is important in mediating resistance to apoptosis in B-cell lymphoproliferative diseases. This study investigates eight polymorphisms across the NFKBIA gene in large patient and control populations. Significant differences in the frequency of particular polymorphisms were noted between patients and controls. A risk haplotype [GCCTATCA] for MM was also identified (P=0.006). Analysis of the genetics of NFKBIA may lead to associations with disease progression and survival and thus more personalized therapy.