Features of extramedullary myeloma relapse: high proliferation, minimal marrow involvement, adverse cytogenetics: a retrospective single-center study of 24 cases

Extramedullary (e) relapse in multiple myeloma(MM) has an adverse prognosis, but knowledge concerning biological features and preferred treatment is scarce. We screened the myeloma registry of our institution for eMM relapses and identified 24 cases among 357 patients (pts).Only 8% of eMM relapses occurred after initial therapy, but 54% occurred after third-line or subsequent therapy. Baseline molecular cytogenetics revealed high-risk features in 10 of 19 evaluable patients. Most frequently, eMM presented as soft tissue (67%) and organ involvement (25%) or malignant effusion (12.5%). Incidence of leptomeningeal/CNS involvement was 21%. At eMM relapse, bone marrow infiltration was absent in 46% and low in 21%. Ten eMM biopsies were available showing increased proliferation, i.e., Ki-67 of 67%(range, 30–90%) of all cancer cells. Pts received radiation therapy, dose-intense chemotherapy, novel agents, and allogeneic SCT resulting in an overall response rate of 54%. Median progression-free survival was 2 (95% CI 0.08–3.92) and median overall survival 7 months (95% CI 3.56–10.43), respectively,with only three patients being alive at 12 months from diagnosis. EMM relapse may present at any anatomical site with frequent CNS involvement. Biological features include increased proliferation and low rate of marrow involvement.Prognosis remains poor despite intensive treatment.     

Changes of smooth muscle contractile filaments in small bowel atresia

AIM: To investigate morphological changes of intestinal smooth muscle contractile fibres in small bowel atresia patients.METHODS: Resected small bowel specimens from small bowel atresia patients (n = 12) were divided into three sections (proximal, atretic and distal). Standard histology hematoxylin-eosin staining and enzyme immunohistochemistry was performed to visualize smooth muscle contractile markers α-smooth muscle actin (SMA) and desmin using conventional paraffin sections of the proximal and distal bowel. Small bowel from age-matched patients (n = 2) undergoing Meckel’s diverticulum resection served as controls.RESULTS: The smooth muscle coat in the proximal bowel of small bowel atresia patients was thickened compared with control tissue, but the distal bowel was unchanged. Expression of smooth muscle contractile fibres SMA and desmin within the proximal bowel was slightly reduced compared with the distal bowel and control tissue. There were no major differences in the architecture of the smooth muscle within the proximal bowel and the distal bowel. The proximal and distal bowel in small bowel atresia patients revealed only minimal differences regarding smooth muscle morphology and the presence of smooth muscle contractile filament markers.CONCLUSION: Changes in smooth muscle contractile filaments do not appear to play a major role in postoperative motility disorders in small bowel atresia.     

Renal function during treatment with adefovir plus peginterferon alfa-2a vs either drug alone in hepatitis B/D co-infection

Long-term safety of treatment with hepatitis B virus (HBV) polymerase inhibitors is a concern. Adefovir dipivoxil (ADV) therapy has previously been associated with impairment of renal function. Limited data are available on the safety of combination therapy with nucleos(t)ide analogues and interferon alfa (IFNα). The aim of this analysis was to assess the renal function during combination therapy with peginterferon alfa-2a (PegIFNα-2a) plus ADV vs either drug alone in patients with hepatitis B/D co-infection. We performed a retrospective analysis of renal function data of patients treated in the Hep-Net/International Delta Hepatitis Intervention Trial 1(HIDIT-1-trial), a European multicenter study to investigate the efficacy of 48 weeks of therapy with PegIFNα-2a+ADV vs either drug alone in 90 patients with chronic hepatitis B/D co-infection. Glomerular filtration rates (GFR) were calculated by Cockcroft-Gault (CG), abbreviated Modification of Diet in Renal Disease (MDRD) study and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. After 48 weeks of therapy GFR values were significantly lower in patients receiving adefovir-containing treatment vs PegIFNα-2a alone [mean difference 16.1 mL/min (CG) and 10.2 mL/min (MDRD), respectively, P < 0.05] while no differences were observed between patients receiving adefovir alone vs combination treatment. Twenty-four weeks after treatment GFR values did not differ between treatment arms. A decrease in GFR ≥ 20% was observed more often in patients during adefovir-containing treatment vs PegIFNα-2a alone (P < 0.05) which was confirmed by Kaplan-Meier analysis. Adefovir-containing but not PegIFNα-2a treatment was associated with a decrease in GFR values in about one-fifth of patients. Combination treatment of PegIFNα-2a+ADV in chronic hepatitis B/D co-infection did not lead to any further impairment of kidney function.     

Modulation of replication efficacy of the hepatitis C virus replicon Con1 by site‐directed mutagenesis of an NS4B aminoterminal basic leucine zipper

Summary. The hepatitis C virus (HCV) nonstructural protein 4B (NS4B) is assumed to function as a membrane anchor and protein hub for the viral replication complex. The aim of the current work was to modulate HCV replication efficacy in the subgenomic Con1 replicon by mutations of specific sites within the aminoterminal‐located basic leucine zipper (bZIP), a candidate motif for protein–protein interactions involving NS4B. Mutational sites and amino acid substitutes were determined by in‐silico sequence analyses of the NS4B‐bZIP motif in 357 isolates of HCV genotype 1b from the euHCVdB and LosAlamos database and consecutive analysis of conserved physico‐chemical properties at bZIP specific positions. Mutants with predicted minor, medium or major reduction of replication efficacy were tested in the pFKI389neo/NS3‐3′/ET plasmid replicon model. Four sites (L25, T29, V39 and W43) of crucial importance for bZIP‐mediated protein interaction with predicted apolarity of respective amino acid positions were selected for mutational studies. Substitutes with physico‐chemical properties matching the predicted requirements either well (T29A), moderately (L25W, V39W), or insufficiently (T29E, W43E) were associated with slightly improved, moderate and marked decreased replication efficacy, respectively. Spontaneous (T29G) and adaptive (A28G, E40G) mutations occurred in the T29E mutation isolate only and were associated with marked reduction of replication efficacy. The bZIP motif region of NS4B is crucial for RNA replication in the subgenomic Con1 replicon system. RNA replication efficacy can be modulated by site‐directed mutagenesis at specific bZIP functional sites. New adaptive amino acid mutations were identified within the HCV NS4B protein.     

Optimized threshold for serum HCV RNA to predict treatment outcomes in hepatitis C patients receiving peginterferon alfa‐2a/ribavirin

Summary. It is unclear whether the current threshold for ‘high’ hepatitis C virus (HCV) RNA level (800 000 IU/mL) is optimal for predicting sustained virological response (SVR). We retrospectively analysed pretreatment HCV RNA levels and SVR rates in 1529 mono‐infected and 176 HIV–HCV co‐infected patients treated with peginterferon alfa‐2a (40 kD) plus ribavirin. We improved the threshold for differentiating low and high viral load by fitting semiparametric generalized additive logistic regression models to the data and constructing receiver operating characteristics curves. Among HCV genotype 1 mono‐infected patients, the difference in SVR rates between those with low and high baseline HCV RNA levels was 27% (70%vs 43%) when 400 000 IU/mL was used and 16% (59%vs 43%) when 800 000 IU/mL was used. In HIV–HCV genotype 1 co‐infected patients, the difference was 51% (71%vs 20%) when 400 000 IU/mL was used and 43% (61%vs 18%) when 800 000 IU/mL was used. A lower threshold (200 000 IU/mL) was identified for genotype 1 mono‐infected patients with ‘normal’ alanine aminotransferase (ALT) levels. No threshold could be identified in HCV genotype 2 or 3 patients. A threshold HCV RNA level of 400 000 IU/mL is optimal for differentiating high and low probability of SVR in genotype 1‐infected individuals with elevated ALT.