The clinical significance of ABCB1 overexpression in predicting outcome of CML patients undergoing first-line imatinib treatment.

Tyrosine kinase inhibitor (TKI) therapy results in excellent responses in the majority of patients with chronic myeloid leukaemia. First-line imatinib treatment, with selective switching to nilotinib when patients fail to meet specific molecular targets or for imatinib intolerance, results in excellent overall molecular responses and survival. However, this strategy is less effective in cases of primary imatinib resistance; moreover, 25% of patients develop secondary resistance such that 20-35% of patients initially treated with imatinib will eventually experience treatment failure. Early identification of these patients is of high clinical relevance. Since the drug efflux transporter ABCB1 has previously been implicated in TKI resistance, we determined if early increases in ABCB1 mRNA expression (fold change from diagnosis to day 22 of imatinib therapy) predict for patient response. Indeed, patients exhibiting a high fold rise (⩾2.2, n=79) were significantly less likely to achieve early molecular response (BCR-ABL1IS ⩽10% at 3 months; P=0.001), major molecular response (P<0.0001) and MR4.5 (P<0.0001). Additionally, patients demonstrated increased levels of ABCB1 mRNA before the development of mutations and/or progression to blast crisis. Patients with high fold rise in ABCB1 mRNA were also less likely to achieve major molecular response when switched to nilotinib therapy (49% vs 82% of patients with low fold rise). We conclude that early evaluation of the fold change in ABCB1 mRNA expression may identify patients likely to be resistant to first- and second-generation TKIs and who may be candidates for alternative therapy.

Ethanol versus heparin locks for the prevention of central venous catheter-associated bloodstream infections: a randomized trial in adult haematology patients with Hickman devices.

The effectiveness of ethanol locks for prevention of central venous catheter (CVC)-associated bloodstream infection (CLABSI) in adult haematology patients has not been thoroughly evaluated. This study aimed to compare prospectively heparinized saline with 70% ethanol locks using 2 h dwell time in patients with tunnelled CVCs. In saline (N = 43) and ethanol (N = 42) groups, CLABSI rates were 6.0 [95% confidence interval (CI): 3.4-9.8] and 4.1 (95% CI: 1.9-7.7) per 1000 CVC days, respectively (P = 0.42). In the ethanol group, two exit-site infections and one tunnel/pocket infection were observed. Reduction in device-associated infection was not achieved with prophylactic 70% ethanol locks in patients with haematological malignancy and tunnelled CVCs.

Patients with chronic myeloid leukemia who maintain a complete molecular response after stopping imatinib treatment have evidence of persistent leukemia by DNA PCR.

Around 40-50% of patients with chronic myeloid leukemia (CML) who achieve a stable complete molecular response (CMR; undetectable breakpoint cluster region-Abelson leukemia gene human homolog 1 (BCR-ABL1) mRNA) on imatinib can stop therapy and remain in CMR, at least for several years. This raises the possibility that imatinib therapy may not need to be continued indefinitely in some CML patients. Two possible explanations for this observation are (1) CML has been eradicated or (2) residual leukemic cells fail to proliferate despite the absence of ongoing kinase inhibition. We used a highly sensitive patient-specific nested quantitative PCR to look for evidence of genomic BCR-ABL1 DNA in patients who sustained CMR after stopping imatinib therapy. Seven of eight patients who sustained CMR off therapy had BCR-ABL1 DNA detected at least once after stopping imatinib, but none has relapsed (follow-up 12-41 months). BCR-ABL1 DNA levels increased in all of the 10 patients who lost CMR soon after imatinib cessation, whereas serial testing of patients in sustained CMR showed a stable level of BCR-ABL1 DNA. This more sensitive assay for BCR-ABL1 provides evidence that even patients who maintain a CMR after stopping imatinib may harbor residual leukemia. A search for intrinsic or extrinsic (for example, immunological) causes for this drug-free leukemic suppression is now indicated.

Etoposide induces more severe mucositis than CY when added to TBI as conditioning in allograft recipients receiving CsA and MTX.

Fractionated TBI and etoposide (FTBI-VP16) conditioning is effective therapy for patients receiving allogeneic stem cell transplants for ALL. One of the major dose-limiting toxicities with this regimen is mucositis although its effect on patients and hospital resources is not well described. To determine the severity of mucositis (WHO grade 3-4) experienced and assess resource utilisation, we compared the non-haematological toxicities of 38 patients receiving FTBI-VP16 with 104 patients receiving CY and TBI (CYTBI). FTBI-VP16 patients were more likely to develop severe mucositis (odds ratio (OR) 6.0 (95% confidence interval (CI) 1.36, 54.42), P<0.01) and its duration was longer (11.5 vs 8 days, P<0.01). Resource utilisation was considerably higher especially in the use and duration of i.v. narcotics and parenteral nutrition, nursing care requirements and plt-transfusion support. Patients receiving FTBI-VP16 conditioning are ideal candidates for new therapies to prevent or reduce the severity of mucositis.

The BH3 mimetic compound, ABT-737, synergizes with a range of cytotoxic chemotherapy agents in chronic lymphocytic leukemia.

As chronic lymphocytic leukemia (CLL) is characterized by overexpression of pro-survival BCL2, compounds that mimic its physiological antagonists, the BH3-only proteins, may have a role in treatment of this disease. ABT-737 is a BH3 mimetic compound that selectively targets BCL2 and BCLX(L). In the present work, we report that ABT-737 is highly effective (LC(50)<50 nM) as a single agent against most (21/30) primary CLL samples, but that a sizable minority is relatively insensitive. In vitro sensitivity to ABT-737 could not be simply predicted by the patients' clinical features, including response to prior therapy or known prognostic markers (CD38 expression, 17p deletion), or the relative expression of BCL2 family proteins (BCL2, MCL1, BAX, BIM). Strikingly, co-incubation with cytotoxic agents (dexamethasone, etoposide, fludarabine, doxorubicin) sensitized most CLL samples to ABT-737, but this could not be predicted by responses to either ABT-737 or the cytotoxic agent alone. Of 17 samples least sensitive to ABT-737, 13 were sensitized by co-treatment with at least one cytotoxic agent. These data indicate that combination of ABT-737 with a second anti-leukemic agent would improve response rates and suggest a potential role for combination therapies that include BH3 mimetics for the treatment of this disease.

Antifungal prophylaxis in adult stem cell transplantation and haematological malignancy.

Antifungal prophylaxis can be recommended in patients undergoing induction chemotherapy for acute myeloid leukemia and treatment for grade 2 or greater or chronic extensive graft versus host disease. The evidence for prophylaxis is less clear in other clinical settings although certain groups such as patients with prolonged neutropenia after stem cell transplants using bone marrow or cord blood sources and with impaired cell mediated immunity secondary to treatments such as Alemtuzumab are at high risk. The decision to use prophylaxis and which agent to use will be influenced by effectiveness, number needed to treat and the likelihood of toxicity and drug interactions. The availability of rapid diagnostic tests for fungal infection and institutional epidemiology will also influence the need for and choice of prophylaxis. Whilst prophylaxis can be beneficial, it may impede the ability to make a rapid diagnosis of fungal infection by reducing the yield of diagnostic tests and change the epidemiology of fungal infection. As non-culture based diagnostic tests are refined and become more available there may be a shift from prophylaxis to early diagnosis and treatment.

Gram-negative organisms predominate in Hickman line-related infections in non-neutropenic patients with hematological malignancies.

BACKGROUND: Catheter-related blood stream infections (CRBSI) cause significant morbidity and mortality in patients with hematological malignancies. Previous studies have identified a predominance of gram-positive organisms causing CRBSI but they included both neutropenic and non-neutropenic patients with solid organ and hematological malignancies. The aim of our study was to evaluate the incidence and microbiological profile of CRBSIs in a specific cohort of patients with hematological malignancies in their non-neutropenic phase of illness. METHODS: A detailed retrospective review was done from January 2003 to December 2005 on all patients with hematological malignancies who had double-lumen non-antibiotic impregnated tunneled CVCs (Hickman catheters) inserted in our hospital to identify those fulfilling our criteria for CRBSI episodes. RESULTS: Amongst 273 evaluable patients, 61 developed CRBSI on 70 occasions. In contrast to previous studies, there was a predominance of gram-negative infections (68%). The majority (73%) of initial CRBSI episodes required catheter removal within 7 days of onset. Vancomycin and cefepime was the most common initial antibiotic regimen used. CONCLUSIONS: This study highlights the predominance of gram-negative infections in our cohort of non-neutropenic patients with underlying hematological malignancies who had Hickman catheters whose lines were not salvageable in the majority of cases. Empiric monotherapy with an antimicrobial agent with broad spectrum gram-negative cover needs to be given upfront pending results of the nature and sensitivity of organisms identified.

Cyclosporin, methotrexate and prednisolone for graft-versus-host disease prophylaxis in allogeneic peripheral blood progenitor cell transplants.

The utility of GVHD prophylaxis with cyclosporin, MTX and prednisolone (CSA/MTX/Pred) in allogeneic PBPC transplants is not well described although there are published data using this combination after bone marrow transplants. The effectiveness of this regimen on the prevention of GVHD was assessed in 107 consecutive sibling and less-than-ideal donor transplant recipients over a 5-year period and compared to that observed in 65 patients receiving standard CSA and short-course MTX without prednisolone. Oral prednisolone was commenced on day +14 at 0.5 mg/kg per day, increased to 1 mg/kg per day on day +21 to day +34 then gradually tapered and ceased by day +100. The cumulative incidence of acute GVHD (grades II-IV) to day 100 in those receiving prednisolone prophylaxis was lower (52 versus 76%, P<0.01). The onset of symptomatic GVHD requiring systemic treatment was delayed from a median of 41 days post transplant to 92 days. When assessment of the cumulative incidence of symptomatic GVHD continued to day +180 incidence became similar (74 versus 78%), there was no difference between the two groups in rates of relapse, transplant-related mortality, infections or chronic GVHD. We conclude that the addition of prednisolone to CSA/MTX delays the onset of early acute GVHD in PBPC recipients but has no impact on the overall incidence of GVHD.

A randomized comparison of empiric or pre-emptive antibiotic therapy after hematopoietic stem cell transplantation.

We performed a randomized comparison of pre-emptive and empiric antibiotic therapy for adult patients undergoing allogeneic or autologous stem cell transplantation. One hundred and fifty-three patients were randomized to receive cefepime either pre-emptively on the day that neutropenia (ANC<1.0 x 10(9) cells/l) developed irrespective of the presence of fever, or at onset of fever and neutropenia (empiric). Although there was no difference between the two arms in the proportion of patients developing fever or in the median number of days of fever, the time to onset of fever was a mean of 1 day longer in each patient on the pre-emptive arm (log rank P<0.001). The number of patients with bloodstream infections was significantly reduced in those receiving pre-emptive therapy (16/75) compared to the empiric arm (31/76) (P<0.01) but this did not translate into an appreciable clinical benefit as measured by days of hospitalization, time to engraftment, use of additional antimicrobial agents or mortality at 30 days. This study does not support the use of pre-emptive intravenous antibiotic therapy in adult stem cell transplant recipients.

A prospective multicenter trial of peripheral blood stem cell sibling allografts for acute myeloid leukemia in first complete remission using fludarabine-cyclophosphamide reduced intensity conditioning.

The role of allogeneic transplantation in patients with de novo acute myeloid leukemia in first complete remission (AML-CR1) is controversial. Aiming to preserve a graft-versus-leukemia effect, but minimize morbidity and mortality from conditioning-related toxicity and graft-versus-host disease (GVHD), we conducted a prospective multicenter study of reduced-intensity conditioning (RIC) as preparation for peripheral blood stem cell sibling allografts in patients with intermediate or poor risk AML-CR1. Conditioning consisted of fludarabine 125 mg/m(2) and cyclophosphamide 120 mg/kg. Thirty-four patients were transplanted with a median age of 45 years; 85% had intermediate risk cytogenetics. Early toxicity was minimal. The overall incidence of grade II-IV acute GVHD was low (21%), but the 3 patients (9%) who developed grade IV GVHD died. Donor T cell chimerism was rapid and generally complete, but complete myeloid chimerism was delayed. Thirteen patients (38%) relapsed, 12 within a year of transplant. The estimated disease-free survival (DFS) and overall survival at 2 years was 56% (95% confidence interval [CI] 39%-71%) and 68% (95% CI 50%-81%), respectively. The incidence of extensive chronic GVHD (cGVHD) was low (24% of surviving patients at 12 months) and most survivors had an excellent performance status. These observations justify a prospective comparison of RIC versus myeloablative conditioning allografts for AML-CR1.

The hyper-CVAD-rituximab chemotherapy programme followed by high-dose busulfan, melphalan and autologous stem cell transplantation produces excellent event-free survival in patients with previously untreated mantle cell lymphoma.

The hyper-CVAD + rituximab (R) programme consists of fractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone + R alternating with high-dose methotrexate + cytarabine (HD MTX/ARA-C) + R. This regimen, when used as initial therapy for patients under 65 years of age with previously untreated mantle cell lymphoma (MCL), results in remission rates of > 85% with a median event-free survival (EFS) of > 50 months, but with a pattern of continuous relapse out to 60 months. We performed a study of hyper-CVAD + R, followed by consolidative peripheral blood progenitor cells autograft [autologous stem cell transplant (AuSCT)] with high-dose busulfan and melphalan (Bu/Mel) conditioning, in patients with responsive disease. Thirteen patients with a median age of 54 (range = 33-61) were treated. Complete remission (CR) was achieved in 12 patients (92%) after hyper-CVAD + R and 12 completed AuSCT after Bu/Mel conditioning. One patient died during the autograft and another declined AuSCT after achieving a CR with hyper-CVAD + R. With a median follow-up from diagnosis of 36 months (range = 16-53 months), the observed 36 months overall survival and EFS are both 92% for the whole cohort. These data confirm the excellent CR rates achieved by the use of hyper-CVAD + R in patients with MCL and suggest that consolidation with Bu/Mel and AuSCT may improve durable disease control when compared to published outcomes of hyper-CVAD + R alone.

Female genital tract graft-versus-host disease: incidence, risk factors and recommendations for management.

Female genital tract graft-versus-host disease (GVHD) is an under-recognized complication of allogeneic stem cell transplantation impacting on quality of life. We describe a prospective surveillance programme for female genital GVHD to better characterize incidence, risk factors and clinical features and the impact of a structured intervention policy. A retrospective audit was conducted on the medical records of all female transplant recipients surviving at least 6 months at a single centre over a 5-year period. Patients commenced topical vaginal oestrogen early post transplant with hormone replacement as appropriate for age, prior menopausal status and co-morbidities. A genital tract management programme included regular gynaecological review and self-maintenance of vaginal capacity by dilator or intercourse. The incidence of genital GVHD was 35% (95% confidence interval (CI) (25, 50%)) at 1 year and 49% (95% CI (36, 63%)) at 2 years. Topical therapy was effective in most cases; no patient required surgical intervention to divide vaginal adhesions. The main risk factor was stem cell source with peripheral blood progenitor cells posing a higher risk than marrow (hazard ratio=3.07 (1.22, 7.73), P=0.017). Extensive GVHD in other organs was a common association. We conclude that female genital GVHD is common, and early detection and commencement of topical immunosuppression with dilator use appears to be highly effective at preventing progression.

Zoledronic acid prevents bone loss after allogeneic haemopoietic stem cell transplantation.

Allogeneic haemopoietic stem cell transplant (alloHSCT) patients are at increased risk of osteoporosis. Zoledronic acid (ZA) is a potent i.v. bisphosphonate; however, there are few data on ZA use after alloHSCT. The aim of this study is to examine the effect of a single 4 mg ZA infusion in alloHSCT patients with either osteoporosis (T-score < -2.5) or rapid bone loss post-alloHSCT. An uncontrolled, prospective study of 12 consecutive patients receiving ZA, predominantly within the first year post-HSCT. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the spine and proximal femur pretransplant, pre-ZA and post-ZA. The median annualized percentage change in total hip BMD between the pretransplant scan and the scan immediately before ZA was -13% (range, -51 to +3.6%). After ZA treatment, the total hip BMD increased by a median of +3.3% (range, -20.4 to +14.8%) in 75% of patients. The median annualized percentage change in femoral neck BMD between the pretransplant scan and the scan immediately before ZA was -13.2% (range, -40 to +1.0%). Post-ZA, femoral neck BMD increased by a median of +1.4% (range, -22.2 to +33.6%). Only one patient continued to lose bone from the femoral neck post-ZA infusion. The median annualized percentage change in spinal BMD pretransplant was -12.5% (range, -38 to +6.9%). Post-ZA, spinal BMD decreased by a median of -2.8% (range, -27.6 to +24.4%). Four patients continued to lose bone from the spine post-ZA. ZA reduces bone loss in most patients after alloHSCT. Our data require confirmation in a larger prospective, randomized study.

Pamidronate reduces bone loss after allogeneic stem cell transplantation.

BACKGROUND: Rapid bone loss occurs from the proximal femur after allogeneic stem cell transplantation (alloSCT). OBJECTIVE: The objective of the study was to evaluate effects of high-dose pamidronate therapy on bone loss (BMD) after alloSCT. DESIGN: This was a randomized, multicenter, open-label, 12-month prospective study of iv pamidronate (90 mg/month) beginning before conditioning vs. no pamidronate. All 116 patients also received calcitriol (0.25 microg/d) and calcium (1000 mg/d), which were continued for another year. MAIN OUTCOME MEASURES: Primary objectives were to compare changes in BMD 12 months after alloSCT at the femoral neck, lumbar spine, and total hip between the treatment arms and assess influences of glucocorticoid and cyclosporin therapy on these changes. RESULTS: Pamidronate reduced bone loss at the spine, femoral neck, and total hip by 5.6, 7.7, and 4.9% (all P < or = 0.003), respectively, at 12 months. However, BMD of the femoral neck and total hip was still 2.8 and 3.5% lower than baseline, respectively (P < 0.05) with pamidronate. Only differences at the total hip remained significant between the two groups at 24 months. Benefits were restricted to patients receiving an average daily prednisolone dose greater than 10 mg and cyclosporin therapy for more than 5 months within the first 6 months of alloSCT. CONCLUSIONS: Pamidronate markedly reduced but did not completely prevent postallogeneic bone marrow transplantation bone loss. BMD benefits were greatest in patients on higher doses of immunosuppressive therapy, but most were lost 12 months after stopping pamidronate. Studies of more potent bisphosphonates or anabolic therapy with PTH after alloSCT are warranted with the aim of durable maintenance of bone mass.

Correlation of T-cell immune response with spontaneous resolution and subsequent relapse of Hodgkin's lymphoma.

To our knowledge, there has been no report of spontaneous regression in a non-immunocompromised adult with classical Hodgkin's lymphoma (HL) in the absence of chemotherapy. We describe spontaneous regression and subsequent relapse of Epstein - Barr virus (EBV)-positive HL in an otherwise healthy male adult. The clinical course was associated with an increase in regulatory T-cell markers within the peripheral blood and diseased lymph node at the time of relapse and with a concomitant reduction in cellular immunity against relevant EBV latent membrane protein tumor-associated antigens. Our findings are in keeping with previous observations that implicate impaired cellular immunity in the immunopathogenesis of EBV-positive HL.

Passive donor-to-recipient transfer of antiphospholipid syndrome following allogeneic stem-cell transplantation.

Autoantibody production following allogeneic stem-cell transplantation is common and is often ascribed to the immune dysregulation associated with graft-versus-host disease. Recent data suggests that donor-memory B cells can be reactivated on exposure to antigen and result in antibody production in the recipient identical to that seen in the donor. Here we describe the production of autoantibodies in a recipient of bone marrow from a donor with systemic lupus erythematosus and antiphospholipid syndrome. Autoantibody appearance was precipitated by the onset of graft-versus-host disease, was identical to that of the donor, and ultimately lead to cerebrovascular thrombosis, which was successfully treated with antiplatelet and anticoagulant therapy.

Autografting followed by rituximab for chemosensitive mantle cell lymphoma: a pilot study and literature review.

Mantle cell lymphoma (MCL) is rarely cured with either conventional-dose chemotherapy or autografting. Recent evidence suggests that anti-CD20 monoclonal antibody therapy (rituximab) in combination with chemotherapy may improve the response rate. We report a pilot study of autografting using busulfan-melphalan conditioning followed by rituximab in 9 patients (median age 52 years) with chemosensitive MCL. Rituximab was given for 4 doses of 375 mg/m(2) between 4 and 10 weeks post-transplant. Three of 5 patients autografted after induction therapy remain alive in clinical and molecular complete remission at 33-50 months post-transplant. Only 1 of 4 patients autografted after relapse remains in complete remission. Two of the 3 patients with persistent marrow molecular positivity post-autograft became negative after rituximab therapy. Molecular negativity was first observed in 2 patients only after rituximab therapy. Overall, 2 patients have relapsed and the remaining 3 died of late-onset respiratory failure, probably reflecting infection and/or aggressive conditioning in an older patient population. These preliminary results, together with a review of the literature, suggest that the combination of autografting and rituximab may lead to durable molecular remissions in patients with chemosensitive MCL. Further studies are required to clarify whether the administration of rituximab: (1) is optimal pre- or post-autograft and (2) impacts on the incidence of infection and idiopathic pneumonitis in this context.

Prognostic features for response and survival in elderly patients with de novo acute myeloid leukemia treated with mitoxantrone and intermediate dose cytarabine.

Forty-three fit elderly patients with de novo acute myeloid leukemia (AML) received chemotherapy with mitoxantrone and intermediate dose cytarabine (MIDAC) in a phase II clinical trial conducted by the Australasian Leukaemia and Lymphoma Group. The main aim of the study was to evaluate the tolerability and efficacy of MIDAC in inducing durable remissions. While the chemotherapy was generally well tolerated, less than half the patients achieved complete remission (CR) after induction and many of those in CR could not receive planned consolidation cycles. The median overall survival for all patients was 6.5 months and the median disease-free survival for those achieving CR was 8.3 months. Only 2 patients survived beyond 4 years. Factors significantly associated with shorter survival were adverse cytogenetics, marrow dysplasia and increasing age. These results suggest that only selected elderly patients with AML are likely to benefit from aggressive chemotherapy and that novel therapies are required to improve the poor prognosis of this group.

A pilot study of targeted itraconazole prophylaxis in patients with graft-versus-host disease at high risk of invasive mould infections following allogeneic stem cell transplantation.

Patients with severe graft-versus-host disease (GVHD) requiring intensive immunosuppression are at high risk of invasive mould infections (IMI). Prophylaxis with an active, oral antifungal agents with reliable absorption in this context is desirable. A total of 44 patients at high risk of post-engraftment IMI received itraconazole solution 2.5 mg/kg b.d. as prophylaxis. Two of the first nine patients, in whom bioavailability was compromised due to significant vomiting and/or diarrhoea, died of probable or proven invasive aspergillus. None of the subsequent 35 patients, some of whom had severe gut GVHD and who received liposomal amphotericin B prophylaxis until itraconazole was reliably tolerated and absorbed, developed IMI. The overall incidence of IMI was substantially lower than in historical controls. Itraconazole was generally well tolerated, with five patients (11%) ceasing the drug due to intolerance or disturbed liver function. Targeted prophylaxis with oral or parenteral antifungal agents in high-risk allograft recipients appears to be effective in reducing the incidence of IMI.