Progressive multifocal leukoencephalopathy with concurrent Richter's syndrome

Progressive multifocal leukoencephalopathy (PML) is a demyelinating infectious disease caused by the JC virus. It was originally described in patients with chronic lymphocytic leukemia (CLL). Richter's syndrome, or transformation to large cell Lymphoma, occurs in approximately 3% of patients with CLL, and carries a poor prognosis. We report a patient with documented PML and concurrent Richter's transformation outside the central nervous system. Before establishing a definitive diagnosis of PML, radiation therapy to the presumed lymphomatous brain lesion had been considered, raising the issue of whether stereotactic brain biopsy should be considered in every patient in a similar situation. Although this is likely a rare occurrence, patients with Richter's transformation documented at an extra-neural site and a brain lesion may benefit from the establishment of an infectious diagnosis which would influence therapy.

Infectious complications of pentostatin therapy

Managing the infectious complications associated with pentostatin (Nipent), used alone or in combination with other agents in patients with low-grade lymphomas, poses a significant problem for clinicians. Since there is limited experience with these therapies, definitive treatment recommendations concerning prophylaxis cannot be made. The panel members discussed the use of valacyclovir (Valtrex) to provide prophylaxis for herpes zoster, trimethoprim/sulfamethoxazole for Pneumocystis, and acyclovir (Zovirax) for varicella zoster. They also considered combinations of pentostatin with agents such as interferon, rituximab (Rituxan), and chlorambucil (Leukeran) and their effect on the immune system. The biology of B and T cells was discussed, with an emphasis on clinical application.

Variations in the low levels of cyclin D1/BCL1 have prognostic value in chronic lymphocytic leukemia

Cyclin D1 (CyD1)/BCL1 (PRAD1) is expressed at high levels in almost all cases of mantle cell leukemia/lymphoma (MCL) and in rare cases of chronic lymphocytic leukemia (CLL). The CyD1/BCL1 protein plays an important role in the progression of cells through the G1 phase of cell cycle. Most of the CyD1/BCL1 protein expression studies are performed using immunohistochemistry. We used a sensitive solid-phase radioimmunoassay (RIA) to quantify CyD1 protein expression in 199 patients with CLL. Of these 137 patients were previously untreated with the rest having had standard chemotherapeutic regimens including alkylating agents and fludarabine before being referred to our center. Median white cell count in these patients was 49x10(3) /microl (range 3.0-438.5x10(3)/microl), hemoglobin level 13.1 g/dl (range 5.2-17.3 g/dl), platelet count 157x10(3) /microl (range 10-377x10(3) /microl), age 58 (range 26-89), and beta2-microglobulin 2.75 mg/dl (range 1.1-14.3). The median radioactivity (CPM) of mononuclear cells obtained from 56 normal individuals was assigned a value of 1. There was no significant variation in CyD1 levels among normal individuals (SD=0. 12). While most CyD1 levels in MCL varied from 6.5 to 15.6, the median CyD1/BCL1 in CLL was 1.4 with 75th percentile under 2.12. Rare CLL cases (3.5%) showed levels between 4 and 8.83. When divided into two groups at the median level, patients with higher CyD1/BCL1 expression had shorter survival (P = 0.03). This remained true when applied only to the previously untreated patients (P=0.05). Despite the relatively low expression, the CyD1/BCL1 levels in univariate analysis were as good or better predictors of survival than Binet (P = 0.03) or Rai (P = 0.05) staging. Furthermore, CyD1/BCL1 levels correlated with serum beta2-microglobulin (P = 0.001), white blood cell count (P = 0.004) and hemoglobin levels at the time of collection (P = 0.0003) but not with lymphocyte count, platelet count or age. The data demonstrate that CyD1/BCL1 is likely to play a significant role in the biology of CLL and can be used as a prognostic indicator. Further studies to clarify the role of CyD1 in the biology of CLL and its value as a prognostic indicator at the time of diagnosis are encouraged.

Management of hospital outbreaks of gastro-enteritis due to small roundstructured viruses

Small round structured viruses (SRSVs, Norwalk-like viruses, NLVs) are the most common cause of outbreaks of gastro-enteritis in hospitals and also cause outbreaks in other settings such as schools, hotels, nursing homes and cruise ships. Hospital outbreaks often lead to ward closure and major disruption in hospital activity. Outbreaks usually affect both patients and staff, sometimes with attack rates in excess of 50%. For this reason, staff shortages can be severe, particularly if several wards are involved at the same time. SRSVs may be spread by several routes: faecal-oral; vomiting/aerosols; food and water. Viruses may be introduced into the ward environment by any of these routes and then propagated by person-to-person spread. In an outbreak setting, the diagnosis can usually be made rapidly and confidently on clinical and epidemiological grounds, particularly if vomiting is a prominent symptom. By the time an SRSV outbreak has been recognized at ward level, most susceptible individuals will have been exposed to the virus and infection control efforts must prioritize the prevention of spread of infection to other clinical areas bycontainment of infected/exposed individuals (especially the prevention of patient and staff movements to other areas), hand-hygiene and effective environmental decontamination. This report of the Public Health Laboratory Service Viral Gastro-enteritis Working Group reviews the epidemiology of outbreaks of infection due to SRSVs and makes recommendations for their management in the hospital setting. The basic principles which underpin these recommendations will also be applicable to the management of some community-based institutional outbreaks.

BAX and PKCalpha modulate the prognostic impact of BCL2 expression in acute myelogenous leukemia

Previously, we demonstrated that the level of BCL2 expression is prognostic in acute myelogenous leukemia (AML). High levels of BCL2 correlate with an adverse outcome when associated with favorable and intermediate prognosis cytogenetics (FIPC), whereas low levels portend an adverse outcome when associated with unfavorable cytogenetics (UC). Because BCL2 function can be modulated by dimerization with family members, like BAX, or by phosphorylation by protein kinase C alpha (PKCalpha), we hypothesize that the relative expression of these proteins in primary leukemic cells might alter the prognostic impact of BCL2 expression. We therefore measured BAX and PKCalpha protein levels in peripheral blood mononuclear cell lysates from 165 newly diagnosed AML patients and correlated the expression of these proteins with BCL2 expression, patient survival, and remission induction success. Expression levels of BAX and PKCalpha were normalized against a control cell line, K562. BAX and PKCalpha expression levels were heterogeneous and did not correlate with the percentage of blasts in the sample (R2 = 0.01 and <0.01). The median expression of both was similar across FAB groups but the range was greater for M4. A similar distribution of expression was observed in all cytogenetic groups, except that patients with inversion 16 demonstrated lower levels of BAX. Individually, neither PKCalpha nor BAX expression was prognostic of response to induction therapy or survival. A similar outcome was obtained when patients were stratified by cytogenetics into FIPC and UC groups. However, the ratio of either BCL2:BAX (B2:BX) or PKCalpha*B2:BX (PK*B2:BX) was highly prognostic. Patients with FIPC and a lower ratio (less than median) of either B2:BX or PK*B2:BX had a significantly higher remission induction rate (88 versus 69%, P = 0.04) and longer survival (median: 141 versus 80.5 weeks, P = 0.007) compared with those with ratios more than median. For patients with UC, values of either B2:BX or PK*B2:BX below the median had an inferior response rate to induction therapy (35 versus 78%, P = 0.0006) and inferior survival outcomes (median survival: 11 versus 53 weeks, P = 0.00002). Interestingly, FIPC and UC patients with antiapoptotic ratios (defined as B2:BX or PK*B2:BX more than median) had identical response rates and survival outcomes. In multivariate analyses, the compound variables of cytogenetics and B2:BX, or PK*B2:BX were independent predictors of survival. These results suggest that expression levels of proteins that affect the functional status of BCL2 modify the prognostic impact of BCL2 and suggest that the role of apoptosis in different cases of AML varies independently in the different cytogenetic subgroups.

High-dose busulphan alone as cytoreduction before allogeneic or autologous stem cell transplantation for chronic myeloid leukaemia: a single-centre experience

Transplant-related morbidity and mortality remain a major problem following stem cell transplantation (SCT). The use of high-dose single-agent busulphan before allogeneic or autologous SCT may be a reasonable compromise between maintaining cytoreductive efficacy and minimizing toxicity in patients with chronic myeloid leukaemia (CML). Seventy patients with CML have received busulphan as the only cytoreductive therapy before SCT on 79 occasions. The probability of survival of the 14 allogeneic recipients (all of whom were undergoing a second transplant from the original donor) was 78% at 5 years. Sixty-five autologous SCT were performed in 56 patients, of whom 40 were in late chronic phase. The actuarial 3-year post-autograft survival was 54% for these 56 first autografts. For patients in chronic phase, the 3-year survival was 76% compared with 30% at 2 years for those with advanced phase disease. Busulphan therapy was well tolerated, and except for mild mucositis little toxicity was experienced. None of these patients developed hepatic veno-occlusive disease (VOD). Nine patients (one allogeneic and eight autologous recipients) received several doses of an intravenous formulation of busulphan with very low toxicity. High-dose busulphan alone appears sufficient to provide adequate cytoreduction and immunosuppression in second allogeneic transplants and is also effective as cytoreduction before autologous SCT in patients with CML.

ATM gene deletion in patients with adult acute lymphoblastic leukemia

BACKGROUND

Loss of heterozygosity (LOH) at the ATM gene (mutated in ataxia telangiectasia [AT] patients) and ATM protein deficiency occur in 14% and 34%, respectively, of patients with chronic lymphocytic leukemia (CLL). ATM protein deficiency also is associated with aggressive disease and worse patient survival. Considering the aberrations in the ATM gene in CLL and the high rate of incidence of lymphoid neoplasias in AT patients, the authors investigated its incidence rate and significance in patients with adult acute lymphoblastic leukemia (ALL).

METHODS

Samples from 36 adults with ALL were analyzed for LOH and homozygous deletion (HD) using a panel of three microsatellite markers located at the ATM gene (D11S2179), the MLL gene (D11S1356), and the BCL1 gene (D11S987) loci. These markers are located within the 11q13-q23 locus.

RESULTS

Of the 36 informative cases, 10 (28%) showed deletions (7 LOH and 3 HDs) at the D11S2179 marker. In two patients, the deletions were extended to the MLL gene locus. These deletions were submicroscopic because only 3% (1 of 36) of patients showed abnormalities involving 11q23 using cytogenetic studies. The authors also estimated the levels of ATM protein in 15 ALL patients and 12 healthy volunteers by radioimmunoassay. The ATM protein levels in cases with LOH at the ATM gene were between 15-50% of those from normal bone marrow. In contrast to CLL patients, patients with LOH or HD at the ATM gene locus showed better survival compared with patients without ATM gene deletions (P = 0.003).

CONCLUSIONS

LOH of the ATM gene and protein deficiency are common in adult ALL, are not demonstrated at the cytogenetic level, and are associated with a favorable prognosis. The authors speculate that ATM deficiency may increase the sensitivity of leukemic blasts to the chemotherapy used during induction and after disease remission in patients with adult ALL. The relatively high frequency of deletion of the D11S2179 marker compared with the D11S1356 marker suggests that ATM is the target gene of the deletion at the 11q23 locus, and that such deletions may play a role in the pathogenesis of ALL.

Prediction of prognosis following fludarabine used as secondary therapy for chronic lymphocytic leukemia

A prognostic factor analysis for survival and response was conducted on 374 previously treated patients who were treated with one of four fludarabine regimens. As several prognostic factors were associated with response and survival, multivariate analyses were conducted to identify the combination of factors which best describe the prognosis as regards response to fludarabine and survival. Statistical models to identify the hazard for survival and probability of response were developed. The characteristics which were included in the model predicting for survival were sex, age, number of prior treatments, performance status, hemoglobin level, serum albumin, and alkaline phosphatase levels. The characteristics most strongly associated with response were the hemoglobin levels, serum albumin, and the number of prior treatments. These models can be used to identify risk groups to guide physicians in decision-making and to assist in the design and analysis of clinical trials.

Cyclophosphamide, ara-C and topotecan (CAT) for patients with refractory or relapsed acute leukemia

Topotecan is a topoisomerase I inhibitor with significant activity in patients with myelodysplastic syndrome and chronic myelomonocytic leukemia. Pre-clinical data suggest a synergistic activity with DNA damaging agents such as cyclophosphamide, where topotecan might prevent the repair of cyclophosphamide-induced DNA damage. We thus designed a combination including cyclophosphamide 500 mg/m2 every 12 hours given on days 1 to 3; topotecan 1.25 mg/m2/day by continuous infusion on days 2 to 6, and cytosine arabinoside (ara-C) 2 g/m2 over 4 hours daily for 5 days on days 2 to 6 (CAT). Sixty six (63 evaluable) patients were treated. Fifty two patients had refractory (n=12) or relapsed (n=40) acute myelogenous leukemia (AML), and eleven had acute lymphocytic leukemia (ALL) (refractory n=3, relapsed n=8); their median age was 57 years (range, 18 to 79 years). Eleven patients (17%) achieved a complete remission (CR), and two patients (3%) had a hematologic improvement (HI; met all criteria for CR except for platelets < 100x10(9)/L), for an overall response rate of 20%. Responses occurred in 12 of 52 AML patients (23%), including 10 CR (19%) and 2 HI (4%), and in 1 of 11 patients with ALL (9%). Myelosuppression was universal; there were 23 episodes of pneumonia or sepsis and 18 episodes of fever of unknown origin complicating 74 courses of CAT. Non-hematologic toxicity was mostly gastrointestinal, including nausea, vomiting, diarrhea and mucositis, but was severe in only 8%. In summary, the CAT regimen is well tolerated and has significant anti-leukemia activity which warrants further investigation.

Expression of thrombopoietin and its receptor (c-mpl) in chronic myelogenous leukemia: correlation with disease progression and response to therapy

BACKGROUND

Chronic myelogenous leukemia (CML) represents a paradigm of the stepwise increment in disease aggressiveness, resistance to therapy, and transformation. Thrombopoietin (TPO) and its receptor, c-mpl, support the proliferation of multiple types of immature hematopoietic progenitor cells, and induce clonal growth of leukemic cells. The authors investigated whether TPO or c-mpl overexpression might correlate with progression of CML, disease aggressiveness, or response to therapy.

METHODS

Expression of c-mpl and TPO was measured in bone marrow samples from 208 patients with CML by Western blot analysis and solid-phase plate radioimmunoassay (used for quantification). Samples obtained from individuals without evidence of hematologic abnormalities were used as controls.

RESULTS

There were no significant differences in TPO or c-mpl expression among patients in different phases of CML or between patients with Philadelphia chromosome positive and negative CML. When TPO and c-mpl levels were analyzed in relation to prognostically important host and disease characteristics in early chronic phase CML, platelet and white blood cell counts demonstrated significant differences in both TPO and c-mpl expression, but age and spleen size demonstrated significant differences in TPO expression only. Responses to interferon (INF)-alpha-based therapy and survival were not influenced by TPO or c-mpl levels.

CONCLUSIONS

TPO or c-mpl overexpression did not correlate with different CML phases, suggesting that they were not involved in CML progression from early to advanced phase. Neither TPO nor c-mpl overexpression was particularly evident in any risk group, suggesting lack of correlation between their expression and disease aggressiveness. This was supported by the finding of similar response to IFN-alpha-based therapy and survival regardless of the level of TPO or c-mpl expression.

Results of treatment with hyper-CVAD, a dose-intensive regimen, in adult acute lymphocytic leukemia

PURPOSE

To evaluate the efficacy and toxicity of Hyper-CVAD (fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone), a dose-intensive regimen, in adult acute lymphocytic leukemia (ALL).

PATIENTS AND METHODS

Adults with newly diagnosed ALL referred since 1992 were entered onto the study; treatment was initiated in 204 patients between 1992 and January 1998. No exclusions were made because of older age, poor performance status, organ dysfunction, or active infection. Median age was 39.5 years; 37% were at least 50 years old. Mature B-cell disease (Burkitt type) was present in 9%, T-cell disease in 17%. Leukocytosis of more than 30 x 10(9)/L was found in 26%, Philadelphia chromosome-positive disease in 16% (20% of patients with assessable metaphases), CNS leukemia at the time of diagnosis in 7%, and a mediastinal mass in 7%. Treatment consisted of four cycles of Hyper-CVAD alternating with four cycles of high-dose methotrexate (MTX) and cytarabine therapy, together with intrathecal CNS prophylaxis and supportive care with antibiotic prophylaxis and granulocyte colony-stimulating factor therapy. Maintenance in patients with nonmature B-cell ALL included 2 years of treatment with mercaptopurine, MTX, vincristine, and prednisone (POMP).

RESULTS

Overall, 185 patients (91%) achieved complete remission (CR) and 12 (6%) died during induction therapy. Estimated 5-year survival and 5-year CR rates were 39% and 38%, respectively. The incidence of CNS relapse was low (4%). Compared with 222 patients treated with vincristine, doxorubicin, and dexamethasone (VAD) regimens, our patients had a better CR rate (91% v 75%, P <.01) and CR rate after one course (74% v 55%, P <.01) and better survival (P <.01), and a smaller percentage had more than 5% day 14 blasts (34% v 48%, P =.01). Previous prognostic models remained predictive for outcome with Hyper-CVAD therapy.

CONCLUSION

Hyper-CVAD therapy is superior to our previous regimens and should be compared with established regimens in adult ALL.

Redox-regulated recruitment of the transcriptional coactivators CREB-binding protein and SRC-1 to hypoxia-inducible factor 1alpha

Hypoxia-inducible factor 1alpha (HIF-1alpha) functions as a transcription factor that is activated by decreased cellular oxygen concentrations to induce expression of a network of genes involved in angiogenesis, erythropoiesis, and glucose homeostasis. Here we demonstrate that two members of the SRC-1/p160 family of transcriptional coactivators harboring histone acetyltransferase activity, SRC-1 and transcription intermediary factor 2 (TIF2), are able to interact with HIF-1alpha and enhance its transactivation potential in a hypoxia-dependent manner. HIF-1alpha contains within its C terminus two transactivation domains. The hypoxia-inducible activity of both these domains was enhanced by either SRC-1 or the CREB-binding protein (CBP)/p300 coactivator. Moreover, at limiting concentrations, SRC-1 produced this effect in synergy with CBP. Interestingly, this effect was strongly potentiated by the redox regulatory protein Ref-1, a dual-function protein harboring DNA repair endonuclease and cysteine reducing activities. These data indicate that all three proteins, CBP, SRC-1, and Ref-1, are important components of the hypoxia signaling pathway and have a common function in regulation of HIF-1alpha function in hypoxic cells. Given the absence of cysteine residues in one of the Ref-1-regulated transactivation domains of HIF-1alpha, it is thus possible that Ref-1 functions in hypoxic cells by targeting critical steps in the recruitment of the CBP-SRC-1 coactivator complex.

Serum beta-2 microglobulin levels are a significant prognostic factor in Philadelphia chromosome-positive chronic myelogenous leukemia

Our objective was to investigate the prognostic significance of serum beta-2 microglobulin (B2M) levels among patients with chronic myelogenous leukemia (CML). All patients with Philadelphia chromosome-positive early chronic phase CML (i.e., within 1 year of diagnosis) treated with IFN alpha-based therapy at the M. D. Anderson Cancer Center between 1980 and 1997, in whom pretreatment B2M levels were available, were investigated. Two hundred one patients were evaluable. Their median B2M was 2.2 mg/dl (range, 1.1-20 mg/dl). Serum B2M levels were associated with other variables of prognostic significance, including age, spleen size, WBC count, percentage of peripheral and marrow blasts, and percentage of marrow basophils. Patients with B2M levels >2.9 mg/dl (ie., the upper quartile of the distribution) had a significantly lower rate of major cytogenetic response compared to those in the lower three quartiles (20 versus 52%; P < 0.01). They also had a shorter survival, with a 5-year survival rate of 48%, compared with 75% for those in the lower quartiles (P = 0.01). High B2M levels (>2.9 mg/dl) could identify a group of patients with an adverse outcome within patients in stage I disease (P = 0.02). Results for patients in stages 2-4 were inconclusive because of the small number of patients in these groups. We conclude that serum B2M levels are an important, and probably independent, prognostic factor for patients with CML in early chronic phase treated with IFN-based therapy.

Chronic myelogenous leukemia in nonlymphoid blastic phase: analysis of the results of first salvage therapy with three different treatment approaches for 162 patients

BACKGROUND

The prognoses of patients with chronic myelogenous leukemia in blastic phase (CML-BP) are extremely poor. Treatment of patients with nonlymphoid CML-BP is associated with very low response rates, a median survival of 2-3 months, and significant toxicities. The aim of this study was to evaluate the results of therapy in CML-BP with different treatments in relation to response rate, survival, and toxicity.

METHODS

A total of 162 adults patients with a diagnosis of nonlymphoid CML-BP referred from 1986 to 1997 were included in this analysis. Only first salvage therapy was considered for the purpose of this analysis. The blastic phase of CML was defined by the presence of 30% or more blasts in the blood or bone marrow, or extramedullary disease. Ninety patients were treated with intensive chemotherapy, 31 with decitabine, and 41 with other single agents.

RESULTS

Thirty-six patients (22%) had an objective response. Response rates were similar among patients treated with intensive chemotherapy (28%) or with decitabine (26%). In aggregate, other single agents showed objective response rates of 7%. The median duration of remission for all patients was 29 weeks and the median overall survival 22 weeks. Patients treated with decitabine showed a trend toward better survival, despite a higher percentage of older patients (P < 0.004). The median survival times were 29 weeks with decitabine, 21 weeks with intensive chemotherapy, and 22 weeks with other agents. When only older patients were considered, survival was significantly better with decitabine versus other treatments (P < 0.01). A multivariate analysis of prognostic factors for survival confirmed the independent, significant favorable effect of decitabine therapy (P = 0.047). In all groups complications of myelosuppression were the most significant side effects. Severe nonhematologic toxicities were not observed in patients treated with decitabine; they occurred in 20% and 17% of patients treated with intensive chemotherapy or other single agents, respectively.

CONCLUSIONS

Compared with intensive chemotherapy, decitabine showed favorable results, with similar objective response rates, a better nonhematologic toxicity profile, and a trend for better survival, particularly among older patients. Studies will now attempt to combine decitabine with other promising approaches, such as homoharringtonine, low dose cytarabine, and interferon-alpha, in all CML phases.

Significance of FHIT expression in chronic myelogenous leukemia

Loss or reduced expression of the fragile histidine triad (FHIT) gene, a tumor suppressor gene localized at chromosome 3p14.2, is common in several solid and hematological cancers and has been associated with tumor progression and worse prognosis. The role of the FHIT gene in the pathogenesis of chronic myelogenous leukemia (CML) or its progression from a chronic phase to the accelerated and blastic phases is not known. The aim of this study was to evaluate whether Fhit protein expression is altered in CML, and whether it plays any role in CML progression, disease responsiveness to therapy, or prognosis. A total of 195 patients with Philadelphia chromosome-positive CML were evaluated, including 129 patients in early chronic phase (time from diagnosis to study, 12 months or less), 30 patients in late chronic phase, and 36 patients in the accelerated and blastic phases. The levels of cellular Fhit protein expression were determined using Western blot analysis and solid-phase RIA and compared to the levels in 31 normal marrows. The median Fhit expression in normal marrows was assigned a value of 1, and the levels in CML samples were normalized to the median of the normal control. Fhit levels in CML samples were evaluated in relation to CML phase and patient characteristics and prognosis in the early chronic phase. The median Fhit value in CML samples was 0.89 (range, 0.34-2.62). Eight of the 195 (4%) CML samples showed Fhit levels <0.5 and lacked detectable Fhit protein by Western blot. There was no difference in the levels of Fhit expression by different CML phases. In early chronic phase, reduced Fhit expression tended to be associated with leukocytosis (P = 0.04) and lower platelet counts (P = 0.01), but not with poorer-risk groups. No differences in response to IFN-alpha therapy or in survival were observed by different Fhit levels. Lack of Fhit protein expression was detected in 4% of CML cases, and reduced expression occurred in a subpopulation of patients. However, reduced Fhit expression is not associated with progression, response to therapy, or prognosis in CML.

A phase I-II trial of escalating doses of mitoxantrone with fixed doses of cytarabine plus fludarabine as salvage therapy for patients with acute leukemia and the blastic phase of chronic myelogenous leukemia

BACKGROUND

Cytarabine is an essential drug for inducing remission of acute myelogenous leukemia, and it is also one the most effective drugs used as salvage therapy for patients with all types of relapsed acute leukemia. Nevertheless, there is considerable room for improvement in the treatment of patients with relapsed leukemia in terms of both the reinduction rate and the duration of response. Fludarabine has been shown to augment responses to cytarabine, possibly by increasing the intracellular concentrations of the active metabolite cytarabine triphosphate. Higher-than-standard doses of mitoxantrone have been shown to augment responses to cytarabine, possibly by increasing the DNA strand breaks induced by topoisomerase II; these strand breaks cannot be effectively repaired in the presence of cytarabine triphosphate. This preliminary study was designed to determine whether moderately high doses of mitoxantrone could be added to the combination of fludarabine and cytarabine in an attempt to improve the combination's antileukemic efficacy.

METHODS

Fifty-five adults with relapsed or refractory acute leukemia or the blastic phase of chronic myelogenous leukemia (CML) received salvage therapy with the FLAM regimen, which consisted of fludarabine, cytarabine, and increasing doses of mitoxantrone.

RESULTS

Even with doses of mitoxantrone escalated to as much as 60 mg/m(2) over 4 days, dose-limiting toxicity was not observed. Overall, the complete response rate was 27.3% (15 of 55 patients, including 4 of 17 with acute myelogenous leukemia [AML], 4 of 12 with acute lymphocytic leukemia [ALL], and 7 of 26 with the blastic phase of CML). The median time to complete response was 42 days. Toxicity other than myelosuppression was manifested primarily as hyperbilirubinemia, which was reversible in all cases. Poor performance status and undifferentiated blastic phase of CML were poor prognostic factors for response to FLAM.

CONCLUSIONS

The FLAM regimen is an active salvage regimen and should be formally evaluated in Phase II studies of patients with AML, ALL, and the myeloid and lymphoid blastic phases of CML.

The usefulness of high dose (7-10mci) gallium (67Ga) scanning to diagnose Richter's transformation

Gallium (67Ga) scan was performed in 29 CLL patients with chronic lymphocytic leukemia who were suspected on clinical grounds to have Richter's transformation (RT). Of 29 patients, nine had a positive 67Ga scan; seven of these had a subsequent biopsy that verified large-cell lymphoma or Hodgkin's disease. The other two patients underwent biopsies that revealed fungal infections, a known cause of 67Ga uptake. Two patients had biopsies that were consistent with RT but showed no affinity to 67Ga. One false negative resulted five days after chemotherapy, a known cause of diminished 67Ga uptake. The other occurred within a small infraorbital mass, containing only 10% centroblasts, which is below the level of detection for 67Ga scanning. Subsequent 67Ga scans in both patients revealed 67Ga avid lesions, which demonstrated RT upon biopsy. This technique was more strongly predictive of RT than was measurement of serum B-2 microglobulin or serum lactate dehydrogenase levels. 67Ga scanning is very useful in localizing an optimal site for biopsy to document RT; it may also have the potential to help assess response to treatment, predict recurrence, and contribute to long-term follow-up in this subset of patients.

De novo CD5+ Burkitt lymphoma/leukemia

CD5 is a T-cell marker aberrantly expressed in B-cell chronic lymphocytic leukemia and mantle cell lymphoma. Other B-cell neoplasms, including Burkitt lymphoma, are usually CD5-. We report 4 cases of de novo CD5+ Burkitt lymphoma/leukemia in elderly patients, all of whom were in a leukemic phase and had variable lymph node and splenic involvement. The blasts were typically medium sized, with folded nuclei, distinct but not prominent nucleoli, and moderate amounts of somewhat vacuolated basophilic cytoplasm; they were terminal deoxynucleotidyl transferase--negative and surface immunoglobulin--positive. All 4 cases demonstrated c-myc rearrangement, but none had t(14;18), t(11;14), or cyclin D1 overexpression or rearrangement. Only 1 patient achieved complete remission after hyper-CVAD (hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone) therapy. One patient responded poorly to hyper-CVAD, and 2 patients died during induction chemotherapy. These rare cases of aggressive lymphoid malignancy with CD5 positivity and molecular features associated with Burkitt lymphoma/leukemia are best classified as Burkitt leukemia. However, the morphologic and immunophenotypic similarity to the blastoid variant of mantle cell lymphoma are diagnostically challenging. The diseases can be distinguished at the genetic level, since Burkitt lymphoma involves the rearrangement of c-myc, and mantle cell lymphoma usually the overexpression or rearrangement of cyclin D1.

Phase I study of liposomal daunorubicin in patients with acute leukemia

The dose of anthracyclines used during induction has been identified as a significant prognostic factor in acute leukemias. Liposomal encapsulation of anthracyclines has been proposed as a way of decreasing toxicity and probably increasing efficacy of these agents, therefore allowing the exploration of high-dose anthracycline therapy in acute leukemias. We conducted a phase I study of liposomal daunorubicin (Daunoxome; DNX) in patients with refractory or relapsed acute leukemias. Patients received three daily doses of DNX at 75, 100, 150 or 200 mg/m2 on each cycle, to a total dose of 225, 300, 450, and 600 mg/m2, respectively. At least three patients were included at each dose level before escalating to the next level, and patients could receive more than one course at the next dose level. Twenty-four patients were included and 23 are evaluable. Fifteen patients received one course, seven received two courses, and one received three courses of DNX. Seventeen patients had previously received anthracyclines. The dose-limiting toxicity was mucositis which occurred (grade 3-4) in 3 of 5 patients treated at 200 mg/m2, 2 of 9 treated at 150 mg/m2 and 1 of 6 at 100 mg/m2. Other non-hematologic toxicity was mild and infrequent. There was no change in post-LVEF among 9 patients with available data and no significant cardiac events were documented. Two patients had a complete response: one patient with chronic myeloid leukemia in refractory blast phase went back to chronic phase, and one patient with second relapse acute promyelocytic leukemia achieved a third complete remission. We conclude that the maximally tolerated dose of DNX in this schedule is 150 mg/m2 and has significant anti-leukemia activity.

Combination of topotecan with cytarabine or etoposide in patients with refractory or relapsed acute myeloid leukemia: results of a randomized phase I/II study

The topoisomerase I inhibitor topotecan has shown activity in acute myeloid leukemia (AML) and myelodysplastic syndromes. The present study was designed to assess whether topotecan with cytosine arabinoside (ara-C) or with etoposide (VP-16) should be studied in phase II trials in patients with refractory or relapsed AML. Patients with refractory or relapsed AML were assigned to one of 3 strata defined by expected CR rates of 7%, 20% and 40%, then randomly assigned to receive topotecan (dl-5) and ara-C (1 g/m2 over 2 hours; dl-5), topotecan (d1-5) followed by VP-16 (250 mg/m2 twice daily, d6-7), or VP-16 (250 mg/m2 twice daily dl-2) followed by topotecan (d3-d7). A dose-finding phase was conducted in the poorest stratum of each arm (topotecan starting dose: 1.0 mg/m2/day x 5). A Bayesian pre-phase II selection design was used to assess whether the CR rate with a given arm was sufficient to merit investigation in phase II. Thirty-seven patients, median age 58 years, were treated. Their median first CR duration was 28 weeks and 24% were primary refractory. Grade 3-4 mucositis occurred in the initial patients in the topotecan --> VP-16, but not in the topotecan + ara-C or VP-16 --> topotecan arms. Consequently, in subsequent patients, the topotecan dose was lower in the topotecan --> VP-16 than in the other 2 arms (1.0 vs 1.25 mg/m2 daily x 5) and the VP-16 dose was lower in the topotecan --> VP-16 arm (200 vs 250 mg/m2 twice daily x 2). One CR occurred (topotecan --> VP-16 arm), and the treatment arms were terminated after 10, 15, and 12 patients were treated on the topotecan + ara-C, topotecan --> VP-16, and VP-16 --> topotecan arms, respectively. The principal cause of failure was insufficient anti-leukemia effect rather than death on study, and toxicity was minimal at the final doses used. We concluded that none of the combinations studied here warrants phase II evaluation in very poor prognosis AML salvage patients.

Unexpected high incidence of severe toxicities associated with alpha interferon, low-dose cytosine arabinoside and all-trans retinoic acid in patients with chronic myelogenous leukemia

Preclinical data have shown that all-trans retinoic acid (ATRA) with interferon-alpha (IFN-alpha) can exert significant suppressive effects on Philadelphia-chromosome (Ph)-positive cells. The aim of this study combining IFN-alpha, low-dose cytosine arabinoside (ara-C) and ATRA was to increase the proportion of patients achieving a major cytogenetic response, in comparison with a group of 140 patients previously treated with IFN-alpha plus low-dose ara-C. Forty three patients with Ph-positive CML in early chronic phase were treated with IFN-alpha 5 MU/m2 s.c. daily, low-dose ara-C 10 mg s.c. daily and ATRA 45 mg/m2 orally daily, for 7 consecutive days every other week. Overall, 76% of patients achieved a complete hematologic response (CHR). A cytogenetic response was in observed 59% (major in 38% and complete in 17%). Compared with patients treated with IFN-alpha and low-dose ara-C, those receiving additional ATRA had a lower CHR rate (p. 014), but other response rates were similar. Severe toxicities were common with the triple regimen (64%), mostly related to ATRA therapy. Two patients experienced pseudotumor cerebri; two patients had leukocytosis during the week on ATRA treatment, decreasing during the week off (one suffered a severe asthma-like reaction followed by pulmonary edema, resembling ATRA syndrome). Six patients had other unusual side-effects: aseptic necrosis of the hip (1 patient), ataxic syndrome (1 patient), paranoid syndrome (2 patients), syncopal episodes (1 patient), pure red cell aplasia (1 patient). In conclusion the results of IFN-alpha and low-dose ara-C combined with ATRA in patients with early CML-chronic phase were disappointing, due to excessive toxicity. Whether different ATRA dose schedules may result in fewer side-effects and improve hematologic and cytogenetic response remains to be determined.

Molecular remissions induced by liposomal-encapsulated all-trans retinoic acid in newly diagnosed acute promyelocytic leukemia

All-trans retinoic acid administered orally (oral ATRA) may not regularly lead to either molecular complete remissions (CRs) or prolonged hematologic CRs (HCR) unless combined with chemotherapy. Because serum tretinoin concentrations are higher, and maintained longer, after use of liposomal-encapsulated ATRA (lipoATRA) rather than oral ATRA, we investigated lipoATRA monotherapy in newly diagnosed acute promyelocytic leukemia (APL). Patients received lipoATRA 90 mg/m(2) every other day for remission induction. The same dose was given 3 times a week until 9 months had elapsed from HCR date. Treatment then stopped. Chemotherapy (idarubicin 12 mg/m(2) daily days 1-2 for 2 courses) was to be added only if 2 polymerase chain reaction (PCR) tests, performed 2 weeks apart, were positive at 3, 6, or 9 months from HCR date. The sensitivity level of the PCR was 10(-4). We treated 18 patients (median age, 54 years; median white blood cell [WBC] count 4,500/microL). The HCR rate was 12/18 (67%, 95% confidence interval [CI], 41% to 87%). This rate was similar to that we observed in a previous study using oral ATRA + idarubicin. Nine of 10 patients studied at HCR date were PCR-positive. Subsequently, however, overall (+/- idarubicin) rates of PCR positivity were 0/12 at 3 months, 1/10 at 6 months, 1/7 at 9 and 12 months, and 0/4 at 15 to 17 months. Idarubicin has been added in 3 patients, with this addition occurring at 6 months in 2 patients and at 9 months in 1 patient. Among patients who had not received idarubicin when the PCR was evaluated, 0 of 12 were PCR-positive at 3 months, 1 of 10 was positive at 6 months, 1 of 6 was positive at 9 months, 0 of 4 were positive at 12 months, and 0 of 3 were positive at 15 to 17 months. Morphologic APL has recurred in 1 patient, with a median follow-up time of 13 months in the 11 patients remaining in first CR. The median follow-up time is 91/2 months (range, 3 to 17) in the 9 patients who have received only lipoATRA and who remain PCR-negative and in first CR. Our data suggest that lipoATRA is an effective means of producing molecular CR in newly diagnosed APL.