Variations in the detection of ZAP-70 in chronic lymphocytic leukemia: Comparison with IgV(H) mutation analysis

Lack of immunoglobulin heavy chain genes (IgV(H)) mutation in patients with chronic lymphocytic leukemia (CLL) is associated with rapid disease progression and shorter survival. The zeta-chain (T-cell receptor) associated protein kinase 70 kDa (ZAP-70) has been reported to be a surrogate marker for IgV(H) mutation status, and its expression in leukemic cells correlates with unmutated IgV(H). However, ZAP-70 detection by flow cytometry varies significantly dependant on the antibodies used, the method of performing the assay, and the condition of the cells in the specimen. The clinical value of ZAP-70 testing when samples are shipped under poorly controlled conditions is not known. Furthermore, testing in a research environment may differ from testing in a routine clinical laboratory. We validated an assay for ZAP-70 by comparing results with clinical outcome and the mutation status of the IgV(H). Using stored samples, we show significant correlation between ZAP-70 expression and clinical outcome as well as IgV(H) mutation at a cut-off point of 15%. While positive samples (>15% positivity) remain positive when kept in the laboratory environment for 48 h after initial testing, results obtained from samples from CLL patients tested after shipping at room temperature for routine testing showed no correlation with IgV(H) mutation status when 15% cut-off was used. In these samples, cut-point of 10% correlated with the IgV(H) mutation (P = 0.0001). This data suggests that although ZAP-70 positivity correlates with IgV(H) mutation status and survival, variations in sample handling and preparation may influence results. We show that IgV(H) mutation results, unlike ZAP-70 remain correlated with CD38 expression and beta-2 microglobulin in shipped samples, and ZAP-70 testing should not be used as the sole criterion for stratifying patients for therapy.

General practitioners role in the notification of communicable diseases - study in Malta

General practitioners (GPs) have an essential role in notification of communicable diseases. The main aim of the study described here was to assess the GPs' awareness of and attitudes towards the notification system in Malta, with special focus on infectious intestinal disease (IID). A questionnaire collecting demographic data, information on reporting practices, opinions on the existing notification system and suggestions for improvement was sent to 256 GPs working in either private or public health sector. In all, 150 GPs took part in the survey (response rate 58.6%). The responses revealed that Maltese GPs were aware of their obligations to notify communicable diseases but often did not report them, relying on the hospitals or laboratories to do so. The Disease Surveillance Unit (DSU) website and medical school training were the main sources of information on notification. Notification forms were obtained from health centres and usually kept at the place of work. Most GPs reported filling in the forms during the patients' visits. Private GPs tended to notify earlier than GPs working in public health centers. Among IID, food-borne illness was reported more frequently than person-to-person transmitted gastroenteritis and was considered to be of a higher priority with regard to public health importance (p<0.001). The survey highlighted also some areas for improvement, including need of feedback especially by direct communication or a newsletter.

Estimating the burden and cost of infectious intestinal disease in the Maltese community

The aim of this study was to estimate the burden of infectious intestinal disease (IID) and cost of illness at the community level from a societal aspect. A retrospective, age-stratified cross-sectional telephone study was carried out in Malta in 2004-2005. The number of cases, resources used and cost of resources were computed. The resources involved direct costs (health-care services, stool culture tests, medicines and personal costs) and indirect costs (costs from lost employment by cases and caregivers). This study estimated 0.421 (95% CI 0.092-0.771) separate episodes of IID per person per year in Malta which corresponds to 164 471 (95% CI 35 941-301 205) episodes of IID per year or 450 (95% CI 98-825) episodes of IID each day. The largest proportion of cost is due to provision of health-care services with euro10 454 901 [Maltese liri (Lm) 4 558 970] per year; followed by euro963 295 (Lm 2 209 393) in lost productivity; euro1 286 286 (Lm 561 078) in medicines; euro152 335 (Lm 66 452) in stool culture testing and euro71 487 (Lm 31 183) in personal costs, giving a total cost of illness of over euro16 million (7 million Lm) per year. The burden and cost of IID are high enough to justify efforts to control the illness. Such estimates are important to assess the cost-effectiveness of proposed specific interventions.

The cemented custom femoral stem--a 10 year review

We report a series of 706 patients (759 hip implants) with an average follow up of 10.5 years (range, 10-11 years) following total hip replacement (THR) using a cemented custom-made femoral stem and a cemented HDP acetabular component. The fate of every implant is known. One hundred and seventy-four patients (23%) were deceased at the time of their 10-year review all died with a functioning THR in situ. Four hundred and sixty-two patients (61%) were subsequently reviewed. One hundred and twenty three patients (16%) were assessed by telephone review, as they were too ill or unwilling to attend. Kaplan-Meier survival analysis (all components) demonstrated a median survival at 10 years of 96.05% or 95% Confidence Intervals (CI) for median survival of (94.41% to 97.22%). Revision surgery occurred in 30 cases (3.9%). Seventeen had full revisions (2.2%) and 13 (1.7%) socket revisions only. Twenty-one out of 30 revisions were for infection or dislocation. There were 2 cases (0.3%) of revision for aseptic loosening of the stem. The 10-year results of the custom femoral titanium stem are encouraging and compare well with other cemented systems.

Public health investigations of Salmonella Enteritidis in catering raw shell eggs, 2002-2004

AIMS

In response to a dramatic change in the epidemiology of Salmonella Enteritidis in England and Wales thought to be associated with raw shell eggs, the Health Protection Agency initiated public health investigations to establish the incidence of Salmonella contamination and origin of eggs used by catering premises implicated in outbreaks of Salm. Enteritidis.

METHODS AND RESULTS

Between October 2002 and November 2004, 16 971 eggs were sampled and Salmonella were recovered from 3.4%. Salmonella was isolated from 5.5% and 6.3% of Spanish and eggs of unknown origin, respectively, used in catering premises linked to outbreaks, a level significantly higher than that (1.1%) found in nonLion Quality UK eggs sampled. The small sample of UK Lion Quality eggs tested (reflecting their lack of use in premises visited) did not contain Salmonella. Several phage types of Salm. Enteritidis other than phage type 4 (PT 4) were identified with nonUK eggs.

CONCLUSIONS

Eggs from Spain were implicated as a major source of infection. Eggs were contaminated more frequently with Salmonella when shells were dirty and/or cracked, and stored at above 8 degrees C.

SIGNIFICANCE AND IMPACT OF THE STUDY

The use of Spanish eggs by the catering sector has been identified as a consistent significant factor in many of the outbreaks caused by Salm. Enteritidis nonPT4 in England and Wales during 2002-2004. Advice to caterers and hospitals that raw shell eggs should not be used in food that will either not be cooked or only lightly cooked should be reinforced.

Salvage therapy following failure or relapse after FCR chemo-immunotherapy as initial treatment for chronic lymphocytic leukemia (CLL)

7009

Background: CLL treatment evolved from single agents to combination chemotherapy to chemo-immunotherapy e.g. fludarabine and rituximab (FR) or with cyclophosphamide (FCR). Reports usually describe initial response, time-to-treatment failure (TTF), and survival. Follow-up of relapsed/failed patients (pts) is rarely reported. This report summarizes our experience with such pts after FCR. Methods: 300 pts initially treated with FCR were analyzed. 15 pts failed, 6 died in remission, six developed Richter's transformation (RT) or another malignancy (14) or relapsed (77). Ten have not required therapy. Results: 67 pts received first salvage therapy (S1) with a variety of regimens. The median age was 59 years and 70% were male. Most pts were Rai stage III - IV (56%). Median TTF after initial FCR was 31 months. Initial FCR responses were CR (36 pts), NPR (10 pts), PR (14 pts), and failure (7 pts). Following S1 therapy, CR was obtained in 17%, NPR (8%) and PR (14%). Initial FCR response of CR or NPR, Rai stage, and β2-microglobulin significantly predicted S1 response. The initial TTF did not predict salvage response. OR rate for FCR-based regimen alone or with alemtuzumab (A) or lumilixamab was 62%, rituximab (R) regimens (31%) and A + R (6/9, 67%). Median survival after S1 therapy was 30 months (28 deaths) and was significantly longer for CR/NPR pts (46 months) than PR/Fail (10 months) P<.001. Duration of initial FCR response, β2-microglobulin level and Rai stage predicted survival (P<.01) but the S1 regimens did not. 9/13 pts who eventually received an allogeneic transplant (allo SCT) are still alive (8 in CR). Conclusions: The results of salvage therapy following FCR initial treatment are unsatisfactory. Patients who failed to obtain a CR or NPR to FCR or S1 therapy should be considered for allo SCT.

No significant financial relationships to disclose.

Central nervous system (CNS) leukemia after imatinib mesylate therapy for chronic myelogenous leukemia (CML)

7042

Background: Imatinib is the standard first line treatment for CML. Imatinib penetrates the CSF poorly. We examined the incidence and outcome of CNS disease in pts with CML treated with imatinib at our institution. Methods: The clinical data for pts with early or late chronic phase and accelerated phase CML treated with imatinib between 1999 and 2006 were reviewed. Pts who were started on imatinib elsewhere and progressed to blast phase were also included. CNS disease was defined as a pathologically proven enhancing lesion (leptomeningeal or parenchymal) or presence of CSF leukemic cells. Results: Nine hundred and ten pts with chronic or accelerated phase CML were treated with imatinib. Fifty five developed blast crisis while on imatinib; another 28 pts had blast transformation while receiving imatinib elsewhere, making up a total of 83 pts. At diagnosis, their median age was 51 yrs, median Hgb, WBC and PLT counts were 10.6 g/dl, 59.7×109/L and 307×109/L, respectively. Median time from diagnosis to starting imatinib was 45.4 mts and the median duration of imatinib therapy was 17.9 mts. Fifteen pts had achieved a complete cytogenetic response and 47 had a complete hematologic response before progressing to blast phase. Their median overall survival from diagnosis was 73.2 mts. Thirty pts developed extramedullary disease; they had similar baseline characteristics as the rest with a median survival of 68.3 mts. Fifteen pts developed CNS disease (5 leptomenigeal, 5 CSF, 3 parenchymal, and 2 spinal cord); 14 had concomitant medullary blast crisis. They had a statistically significant younger age at diagnosis (41.9 vs 52.4 yrs), lower platelet counts (186 vs 334×109/L), and shorter overall survival (66.7 vs 73.2 mts) compared to the other pts with blast phase. Conclusions: CNS disease occurs infrequently in pts receiving imatinib for CML but should be suspected in pts with relevant symptoms. Pts developing CNS leukemia had a worse prognosis; this may be secondary to an inherently worse disease, poor CSF penetration of imatinib, and subsequent difficulty in eradicating CNS disease using available therapies. More potent tyrosine kinase inhibitors, such as nilotinib and dasatinib, and new agents with the ability to cross the blood-brain barrier should be evaluated in this setting.

No significant financial relationships to disclose.

Use of dasatinib in patients (pts) with previously untreated chronic myelogenous leukemia (CML) in chronic phase (CML-CP)

7005

Background: Dasatinib (formerly BMS-354825) is a multi-targeted kinase inhibitor of BCR-ABL and SRC. Based on its high level of activity in pts with imatinib (im) resistant/intolerant CML-CP, the present phase II trial was designed to study previously untreated CML-CP pts treated with dasatinib. The primary objective was to estimate the proportion of pts attaining major molecular response (BCR-ABL/ABL ratio =0.05% by qPCR) at 12 months (mo). Methods: All pts received dasatinib orally 100 mg/day, and were randomized to either a 50 mg-twice-daily or a 100 mg-once-daily schedule. Dose escalation to 140 mg/day and 180 mg/day for poor response or dose reduction to 80 mg/day and 40 mg/day for toxicity, maintaining the same schedule, was allowed. Results: Of the 31 pts enrolled between 11/05 and 12/06; 52% were female; median age was 41 years (range 18–76). At 3 mo, complete hematologic response (CHR) and major cytogenetic response both occurred in 21 (81%) of 26 evaluable pts and complete cytogenetic response (CCyR) in 19 (73%) pts. After 6 mo of therapy, 20/21 (95%) evaluable pts had achieved CCyR. This compares favorably with a CCyR at 6 mo of 54% with im 400 mg/day and 85% with im 800 mg/day, in historical data of similar patients treated in studies at MD Anderson. At 9 mo, 4/15 (27%) evaluable pts had achieved a major molecular response. The most common non-hematologic adverse events (AE) included dyspnea (8 pts), fatigue (7 pts), muscle pain (6 pts), and headache (5 pts) and were predominantly grade (gr) 1–2. Pleural effusion occurred in only 3 pts (gr 1–2 in all). Grade 3–4 hematologic toxicity (transient) included anemia in 4 pts, neutropenia in 7 pts, and thrombocytopenia in 4 pts. With a median duration of therapy of 10 mo, 13 pts required transient treatment interruption, 9 due to non-hematologic toxicities, 3 due to hematologic toxicities, and 1 due to both. The actual median daily dose for all pts was 100mg. No difference in AEs has been observed between dose schedules. Conclusions: Rapid, complete cytogenetic responses to dasatinib 100 mg/day have been observed in a high percentage of patients with previously untreated CML- CP. Accrual to this trial continues.

No significant financial relationships to disclose.

Combination therapy with alemtuzumab and pentostatin is effective and has acceptable toxicity in patients with T-lymphoid neoplasms

7037

Background: The development of effective therapeutic strategies for T-lymphoid neoplasms has been difficult partly due to the paucity of clinical trials. These neoplasms are generally refractory to traditional chemotherapy regimens. Alemtuzumab and pentostatin have response rates of 50% to 65% when used individually to treat various T-cell leukemias and lymphomas. However, most responses are partial and of limited duration. Methods: We have treated 20 patients (pts) with T-lymphoid malignancies (11 T-PLL, 1 ATL, 1 PTCL, 2 T- ALL, 3 γd-T cell hepatosplenic lymphoma, 2 T-LGL) with a combination of alemtuzumab 30 mg IV, 3 times weekly for up to 3 months and pentostatin 4 mg/m2 weekly×4 followed by alternate weekly administration for up to 6 months. Prophylactic antibiotics were administered during the treatment and for 2 months after its completion. Results: The median age of pts was 57 yrs (range, 22 –79 yrs), median WBC was 43.9×109/L (range 0.6 –279.5 x109/L), and median serum β2M was 4.1 mg/L (range, 1.7 –10.8 mg/L). Four pts had splenomegaly, and 6 lymphadenopathy. Thirteen had prior therapy (median 2). Twelve pts have responded (10 CR, 2 PR) for an overall response rate of 60% (including 8 of 11 T-PLL, 1 of 1 ATL, 0 of 2 T-ALL, 2 of 3γd-T cell hepatosplenic lymphoma, 0 of 1 PTCL and 1 of 2 T-LGL). Monoclonal T-cell receptor chain gene rearrangements were detected by PCR in 18 pts and became negative in 5 of 7 evaluable pts in CR. Median response duration has not been reached (range, 0 to 78 weeks). 3 pts have proceeded to allogeneic stem cell transplant, 4 (1 with ATL, 2 with T-PLL, and 1 with T-LGL) have died from disease progression after a response, and 8 were refractory to therapy. Opportunistic infections included reactivation of CMV in 7 pts, reactivation of HSV in 1 pt, recurrence of pre-existing Serratia pneumonia in 1 pt and Aspergillus pneumonia in 2 pts. Unexplained, marked and sustained pancytopenia occurred in 2 pts. Other toxicities were mainly grade 1 and 2 and included nausea, fever, edema, and shortness of breath. Conclusions: The combination of alemtuzumab and pentostatin is feasible and effective in T-cell neoplasms. Although infections including CMV reactivation are a concern, they may be minimized with adequate prophylactic antibiotic therapy.

No significant financial relationships to disclose.

Seventy percent of complete responders remain in continuous remission: Five-year follow-up of 300 patients treated with fludarabine, cyclophosphamide, and rituximab (FCR) as initial therapy of CLL

7008

Background: The early results of 224 CLL patients receiving the FCR regimen were previously reported (JCO 23:4079). Mature follow-up data (median 62 months for survivors) is now available for the complete cohort of 300 patients. Methods: Eligible patients were =16 years old with previously untreated CLL requiring therapy. Median age was 57 years (31%=60 years, 14% =70 years), and 61% & 36% were in modified Rai intermediate & high risk categories respectively. Prognostic factors: B2m >2x normal 42% (n=295), CD38 positive 28% (n=253), abnormal metaphase cytogenetics 29% (n=221), IgVH unmutated 66% (n=94), ZAP-70 positive 49% (n=88). The planned six cycles of therapy were completed in 74% patients. Results: Responses were: 72% CR, 11% nodular PR (PRn) & 12% PR. On multivariate analysis, CR rates were inferior in patients with B2m >2N (p=0.001) and white cell count >150 × 109/L (p=0.01). Rai stage, CD38 positivity, IGVH mutational status and ZAP-70 positivity were not associated with inferior CR. Median Times to Progression (TTP) were 80 months for CR (n=216), 80 months for PRn (n=32) & 27 months for PR (n=36), with 77%, 65% and 28% projected to be progression-free at five years; projected 5 yr survival were 90%, 81% and 37% respectively. Restricting the analysis to 190 patients with at least five years followup, actual 5 yr TTP and 5yr survival were 70% & 88% respectively in complete responders. Five cases of Richter transformation and eight cases of MDS/AML occurred during remission, with projected 5 yr risk of 2% & 3% respectively. When compared with a historical cohort of patients receiving fludarabine (n=190) or fludarabine and cyclophosphamide/mitoxantrone (n=140) in multivariate analysis, FCR was independently associated with superior TTP (p<0.001) and survival (p<0.001). Conclusion: FCR is the most effective CLL frontline regimen reported to date. 70% of complete responders remain progression-free at five years.

No significant financial relationships to disclose.

A phase I study of INNO-406, a dual inhibitor of Abl and Lyn kinases, in adult patients with Philadelphia chromosome positive (Ph+) chronic myelogenous leukemia (CML) or acute lymphocytic leukemia (ALL) relapsed, refractory, or intolerant of imatinib

7046

Background: INNO-406 is an orally available, dual Abl/Lyn kinase inhibitor that is up to 55-times more potent than imatinib in Bcr-Abl cell lines. Numerous Bcr-Abl mutant proteins (not T315I) are sensitive to INNO-406 in vitro. INNO-406 demonstrates specific Src kinase activity against Lyn kinase. Methods: In this phase I study, patients with imatinib-resistant or intolerant Philadelphia (Ph+) chromosome- positive leukemias were eligible for treatment with INNO-406 once a day, orally. Results: 14 pts [median age: 58 yrs (range 18–74); 7 male, 7 female; median CML duration: 53 mo. (range 14–266); and median time on imatinib 45 months (range 12–129); chronic phase CML (8 pts), accelerated phase CML (2 pts), blast phase CML (1 pt), Ph+ ALL (3 pts); previous treatment with nilotinib (5 pts), dasatinib (6 pts)] have been enrolled in the following dose cohorts (mg/day): 30 (3 pts), 60 (3), 120 (6) and 240 mg (2), and have been on treatment between 7 and 123 days. 3 pts remain on study; 10 pts discontinued with disease progression [data unmonitored]. 6 patients who have completed >1 month of treatment, 3 have evidence of clinical response. Patient 5, a chronic phase CML treated with imatinib for 69 mo. before developing resistant disease with an Y253H mutation, had a minimal cytogenetic response after 1 month of INNO-406 therapy. Patient 4, an accelerated phase CML treated with imatinib and nilotinib for 16 and 6 mo., respectively, before becoming intolerant to nilotinib due to thrombocytopenia, has maintained a complete hematologic response following 4.5 months of INNO-406 therapy at a dose of 120 mg/day. Patient 1, a chronic phase CML treated with imatinib for 51 mo. before developing resistant disease without a mutation, has maintained stable white cell counts after 4 months of therapy at a dose of 30–60 mg/day, with a 55-fold reduction in Bcr-Abl transcript levels after 1 month of INNO-406 therapy. Conclusions: INNO-406 is well tolerated in patients at a dose of 240 mg/day, with encouraging evidence of clinical activity in imatinib-resistant and nilotinib-intolerant patients. In the absence of dose limiting toxicity, dose escalation continues.

No significant financial relationships to disclose.

Effect of hematologic improvement (HI) on survival in patients (pts) given targeted therapy (TT) as initial treatment of acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome (HR-MDS)

7059

Background: Recent years have seen the introduction of TT for pts with AML and HR- MDS (> 10% marrow blasts). New criteria, less stringent than those for CR, for response to these agents have been promulgated, giving rise to the response category HI. However, the effect of achieving HI on survival is uncertain. Methods: 180 pts, median age 73, with AML or HR-MDS received TT, most commonly decitabine (69 pts), from 2000–2006. Treatment-related death occurred in 11%, CR in 28%, CRp in 6%, and 55% (99 pts) were resistant. We examined survival in these 99 according to whether TT produced HI, blood count criteria for which were as defined by the International Working Group (IWG) for MDS. Initially, we, unlike the IWG, did not require any duration of HI, however; in subsequent analyses, we required durations of = 4 weeks (HI-4) and, like the IWG, = 8 weeks (HI-8). Results: Survival time dated from start of TT was similar in the 32 pts who achieved HI and the 67 who did not. However, the 13 pts with HI-8 lived longer than those with shorter or no HI (48% vs. 11% at 2 years, p=0.01) as did the 14 with HI-4 (p=0.01). Because HI-4 and HI-8 pts had to live long enough to achieve and maintain HI, we re-did the analysis including only the 84 pts who lived = 67 days from start of TT, the median time needed to observe HI-4. This analysis, which included HI-4, age, and cytogenetics as predictors of survival, indicated that HI-4 was the strongest predictor of longer survival (HR 0.34, 95% CI 0.13–0.86, p=0.02). Results were analogous when we limited the analysis to the 68 pts who lived at least 138 days, by which time 75% of HI-4 pts had achieved HI (p=0.06). Conclusions: Our results suggest that HI-4 (or HI-8 as defined by the IWG) following TT confers a survival benefit in AML or HR-MDS.

No significant financial relationships to disclose.

Phase I study of s-trans, trans-farnesylthiosalicylic acid (FTS), a novel oral Ras inhibitor, in patients with refractory hematologic malignancies

7071

Background: Ras activation (mutational or non-mutational) is a key pathway for survival and proliferative advantage of leukemic cells. Farnesyl transferase inhibitors (FTI) that are thought to alter lipid modification of Ras and thereby alter its membrane targeting, are in clinical trial in hematologic malignancies but their target may not be specific for Ras. Toxicities of FTIs include diarrhea, skin rash and hepatic toxicity. FTS is an oral Ras inhibitor that causes dislocation of Ras from its membrane location by competing directly with farnesylated Ras to bind to its putative membrane binding proteins. FTS does not inhibit farnesyl transferase enzyme. Methods: We report on an ongoing phase I study of FTS in patients with relapsed/refractory hematologic malignancies in which FTS is administered orally twice daily on days 1–21 of a 28 day cycle in a “3+3” dose escalation design. Results: To date, 12 patients (pts) have been enrolled, with 11 pts treated (1 cycle=3, 2 cycles=5, 4cycles=1, 2= too early). Four pts were enrolled at dose level (DL) of 100 mg , 3 pts at each DL of 200 and 400 mg and 2 pts at DL of 600 mg. One pt enrolled at 100 mg DL was never treated. Median age was 74 years (range, 57 to 85 years), median ECOG status 1 (range, 0–2) and median no. of prior therapies 2 (range, 0–7). Diagnoses included: Acute myelogenous leukemia (AML) = 6 pts, myelodysplastic syndrome (MDS) = 4 pts, chronic myelomonocytic leukemia (CMML) = 1 pt and chronic myelogenous leukemia (CML) = 1 pt. Of 9 pts evaluable for response, 6 pts (3 MDS, 1 CMML, 2 AML) had hematological improvement (HI) (3 in two lineages, 3 in one lineage). Grade 1 diarrhea has been the only non-hematologic toxicity seen, observed in 8 of 10 (80%) pts evaluable for toxicity and is completely correctable with oral antidiarrheals. Conclusions: FTS shows promising activity in refractory hematologic malignancies and to date has minimal toxicity.

No significant financial relationships to disclose.

Sentinel Surveillance: an option for surveillance of infectious intestinal disease

Sentinel surveillance systems offer advantages over passive surveillance which is known to have limitations due to incomplete reporting. Sentinel surveillance gathering data from selected sources was piloted as an option for surveillance of infectious intestinal disease (IID) in Malta. Between October 2004 and May 2005, 22 general practitioners (GPs) voluntarily participated in the study and reported on the number of IID cases (by age and sex) and all primary care encounters in their practice. The GPs' reporting activity lasted for 35 weeks, covering a total of 55,425 primary care encounters, of which 1.95% concerned IID. For every case reported via the routine passive notification system, seven cases would be picked up by this enhanced sentinel surveillance.

High-dose caspofungin combination antifungal therapy in patients with hematologic malignancies and hematopoietic stem cell transplantation

Pneumocandins have concentration-dependent antifungal activity and higher dose of caspofungin (HD-CAP) in combination with other licensed antifungal therapy (OLAT) may improve response. Thirty-four patients who received HD-CAP were compared with 63 patients who received standard dose (SD)-CAP. There were no differences between the groups in either patient or disease characteristics. Significantly more patients in the HD-CAP arm had extrapulmonary infections (29 vs 8% in SD group; P=0.0053), and non-Aspergillus species infection (21 vs 6%; P=0.05) and had received prior antifungal therapy (71 vs 33%; P=0.0004). No serious adverse reactions were noted in patients receiving HD- or SD-CAP therapy. Twelve weeks after treatment commenced 44% had a complete or partial response compared with 29% in SD-CAP group (P=0.1). Logistic regression analysis showed a significant probability of a favorable outcome at 12 weeks in patients who received HD-CAP (OR 3.066, 95% CI, 1.092-8.61; P=0.033). This may in part reflect higher number of patients in HD group had received granulocyte-macrophage colony-stimulating factor (41 vs 14% in SD group; P=0.04) and/or interferon gamma (26 vs 5% in SD group; P=0.003) immune enhancement. Further studies are needed to evaluate efficacy of HD-CAP in severely immunosuppressed cancer patients with invasive fungal infections.

Prevalence and estimated incidence of blood-borne viral pathogen infection in organ and tissue donors from northern Alberta

To determine the potential safety benefit of introducing nucleic acid testing (NAT) in tissue and organ donors, the risk of virus transmission was examined in a Canadian population. Anonymous data on Northern Alberta tissue and organ donors from 1998 to 2004 were used to determine the seroprevalence and estimate the seroincidence and residual risk of HIV, HBV, HCV and HTLV infection. Of the 3372 donors identified, 71.1% were surgical bone, 13.2% were living organ and 15.6% were deceased organ/tissue donors. Seroprevalence was: HIV 0.00%, HBV 0.09%, HCV 0.48% and HTLV 0.03%. Incidence (/100,000 p-yrs) and residual risks (/100,000 donors) could only be estimated for HBV (24.2 and 3.9) and HCV (11.2 and 2.2). Risk estimates were higher for deceased donors than surgical bone donors. HCV had the highest prevalence and HBV had the highest estimated incidence. HIV and HTLV risks were extremely low precluding accurate quantification. In this region of low overall viral prevalence, HCV NAT would be most effective in deceased organ donors. In surgical bone donors the cost of implementing NAT is high without significant added safety benefit.

Soluble phosphorylated fms-like tyrosine kinase III. FLT3 protein in patients with acute myeloid leukemia (AML)

FLT3 ligand (FL) has a significant role in the proliferation and differentiation of hematopoietic cells. Mutations in the FLT3 receptor gene have been reported in 30% of patients with AML. We investigated whether abnormal phosphorylation of FLT3 may be more common in AML. We evaluated FLT3 protein and its phosphorylation in the plasma from 85 patients with AML, 16 patients with myelodysplastic syndrome (MDS) and 5 patients with acute lymphoblastic leukemia (ALL). There were no significant differences in the level of plasma FLT3 protein level in the different diseases (p=0.57). AML patients had a significantly higher level of phospho-FLT3:FLT3 ratio (p=0.02). FLT3-ITD and FLT3 point mutations were present in 27 (32%) of the AML patients. Phosphorylated FLT3 was significantly higher in the plasma from patients with FLT3 mutation (p=0.002). Overall, there was no correlation between survival and the plasma level of FLT3 protein or its phosphorylated form. However, amongst the patients without FLT3 mutations, those with a higher level of phosphorylated FLT3 had a significantly shorter duration of remission (p=0.04). Other mechanisms may be responsible for abnormal phosphorylation of FLT3 and inhibitors of FLT3 should also be investigated in patients without mutations.

Frequency and clinical significance of BCR-ABL mutations in patients with chronic myeloid leukemia treated with imatinib mesylate

Mutations of the BCR-ABL kinase domain are a common mechanism of resistance to imatinib in chronic myeloid leukemia. We screened for mutations 171 patients failing imatinib therapy. Sixty-six mutations in 23 amino acids were identified in 62 (36%) patients not responding to imatinib. Phosphate-binding loop (P-loop) mutations were the most frequent (n=24; 36%). By multivariate analysis, factors associated with development of mutations were older age (P=0.026) prior interferon therapy (P=0.026), and accelerated phase or blast phase at time of imatinib failure (P=0.001). After a median follow-up of 38 months (range, 4-68 months) from the start of imatinib therapy, seven patients with non-P-loop and two with P-loop mutation died. By multivariate analysis, development of clonal evolution and higher percentage of peripheral blood basophils were associated with worse survival from the time of imatinib failure. Mutation status had no impact on survival. When survival was measured from the time therapy started, non-P-loop mutations together with duration of response and transformation at the time of failure to imatinib were associated with shorter survival. In conclusion, P-loop mutations were not associated with poor outcome, suggesting that the prognosis of patients who fail imatinib is multifactorial.