From March 1993 to October 1993, 20 consecutive, newly diagnosed acute promyelocytic leukemia (APL) patients from 13 Italian institutions entered in a pilot study named AIDA, combining all-trans retinoic acid (ATRA) with idarubicin (IDA). ATRA was administered orally beginning on the first day of induction at the dosage of 45 mg/m2/d until complete remission (CR), whereas IDA was administered intravenously at the dosage of 12 mg/m2/d on days 2, 4, 6, and 8 of the induction. Patients who achieved CR were consolidated with 3 courses of chemotherapy without ATRA; thereafter, they were followed up for molecular and hematologic CR. The median age was 35.3 years (range, 6.5 to 67.6 years); 8 patients were males and 12 females; 4 had the hypogranular variant of APL (M3v), and 4 (2 with M3v) presented with leukocyte counts > or = 10,000/microL. Molecular analysis for the promyelocytic leukemia-retinoic acid receptor alpha (PML-RAR alpha) hybrid gene at diagnosis was performed in 16 patients by means of reverse transcription-polymerase chain reaction (RT-PCR) analysis, and all were RT-PCR+ for the hybrid gene. In the remaining 4 patients, the cytogenetic study showed the presence of the t(15;17). After a median time of 36 days (range, 28 to 52 days) 18 (90%) patients achieved CR; the remaining 2 patients died 12 and 34 days after diagnosis from myocardial infarction caused by fungal myocarditis and from massive hemoptysis, respectively. ATRA syndrome was observed in only 2 patients, and, after the prompt discontinuation of ATRA and initiation of dexamethasone, both recovered from the syndrome. However, after recovering, 1 patient achieved CR, whereas the other died at day 34 because of massive hemoptysis; other side effects were very limited. At recovery from the third consolidation course, only 3 of 14 (21.4%) tested patients were RT-PCR+ for the PML-RAR alpha hybrid gene. Of these, 2 relapsed shortly afterwards; however, in the last patient, the PML-RAR alpha disappeared at successive testing performed 2 months later. As of September 30, 1995, after a median follow-up period from diagnosis of 27 months (range, 24 to 31 months), the overall survival and event-free survival durations are 85% and 69%, respectively; moreover, 14 of 18 (78%) patients who achieved CR are still alive and in first molecular and hematologic CR. Of the 4 relapsed patients, 3 achieved a second CR with ATRA and, after further treatment, are now in molecular and hematologic CR after 4+, 16+, and 17+ months from the second CR. These results indicate that (1) the AIDA protocol is highly effective in treating APL; (2) after 3 consolidation courses, the majority of patients who achieved CR are RT-PCR- for the hybrid gene PML-RAR alpha; (3) the persistence of an RT-PCR positivity for the PML-RAR alpha hybrid gene after 3 consolidation courses is indicative of early relapse, thus these patients still require additional treatment. These results have prompted the Gruppo Italiano Malattie Ematologiche Maligne dell'Adulto (GIMEMA) to initiate, in cooperation with the Associazione Italiana di Ematologia ed Oncologia Pediatrica and some European Organization for Research and Treatment of Cancer (EORTC) centers, a new multicentric clinical trial named AIDA LAP 0493 for the treatment of adult and pediatric APL patients. All patients are considered eligible if APL diagnosis is confirmed with molecular or cytogenetic studies for PML-RAR alpha hybrid gene or t(15;17) and are enrolled to receive the same induction and consolidation therapy of this pilot study. After consolidation, patients who are RT-PCR- for PML-RAR alpha hybrid gene are randomized to four arms, whereas patients who are RT-PCR+ after consolidation undergo, if eligible, an allogenic transplantation procedure.

A phase III prospective randomized multicenter study was performed to determine whether quinine could improve the response rate of poor-risk acute leukemias (ALs) to standard chemotherapy including a multidrug resistance (MDR)-related cytotoxic agent. The rationale of the study was based on the negative prognostic value of MDR phenotype in ALs and the ability of quinine to reverse this phenotype both in vitro and ex vivo. Three hundred fifteen patients (median age, 49 years; range, 16 to 65) with relapsed (n = 108) or refractory (n = 32) acute myeloblastic leukemia (AML), relapsed (n = 27) or refractory (n = 9) acute lymphoblastic leukemia (ALL), secondary AL (n = 22) or blastic transformation of myelodysplastic syndrome ([MDS] n = 74) or myeloproliferative syndrome ([MPS] n = 43) were randomly assigned to receive mitoxantrone ([MXN] 12 mg/m2/d, days 2 to 5) and cytarabine ([Ara-C] 1 g/m2/12 h, days 1 to 5) alone or in combination with quinine (30 mg/kg/d, days 1 to 5; continuous intravenous infusion beginning 24 hours before MXN infusion). Side effects of quinine were observed in 56 of 161 quinine-treated patients and disappeared in all but four cases after one or two 20% dose decreases. Sera from quinine-treated patients showed increased MXN uptake in an MDR-positive cell line compared with matched sera obtained before quinine infusion. Quinine induced a significant increase in the incidence of nausea, vomiting, mucositis, and cardiac toxicity. A complete response (CR) was observed in 85 of 161 patients (52.8%) from the quinine-treated group versus 70 of 154 patients (45.5%) in the control group (P = .19). The most important differences between quinine and control group CR rates were observed in patients with refractory AMLs and blastic transformation of MDS and MPS. The CR rate was higher in P-glycoprotein-positive cases, although the difference was not significant. Failure of the regimen due to blastic persistence or blast number increase was higher in the control group (61 of 154 patients) than in the quinine group (45 of 161, P = .04). Early death was observed in eight cases (four in each arm) and death in aplasia in 27 cases (20 in quinine group v seven in control group, P = .01). The significant increase of toxicity in the quinine arm could have masked the clinical benefit of MDR reversion in poor-risk ALs.

IgG-HD37-SMPT-dgA is a deglycosylated ricin A chain (dgA)-containing immunotoxin (IT) prepared by conjugating the monoclonal murine (MoAb) anti-CD19 antibody, HD37, to dgA using the heterobifunctional hindered disulfide linker, N-succinimidyl-oxycarbonyl-alpha-methyl-alpha-(2-pyridyldithio) toluene (SMPT). In this report, we have used two regimens for the administration of IgG-HD37-SMPT-dgA to patients with non-Hodgkin's lymphoma (NHL) in two concomitant phase I trials. One trial examined four intermittent bolus infusions administered at 48-hour intervals. The other studied a continuous infusion (CI) administered over the same 8-day period. In the intermittent bolus regimen, the maximum tolerated dose (MTD) was 16 mg/m2/8 d and the dose-limiting toxicity (DLT) consisted of vascular leak syndrome (VLS), aphasia, and evidence of rhabdomyolysis encountered at 24 mg/m2/8 d. Using the CI regimen, the MTD was defined by VLS at 19.2 mg/m2/8 d. At the MTD of both regimens, a novel toxicity, consisting of acrocyanosis with reversible superficial distal digital skin necrosis in the absence of overt evidence of systemic vasculitis, occurred in 3 patients. Of 23 evaluable patients on the bolus schedule, there was 1 persisting complete response (CR; > 40 months) and 1 partial response (PR). Of 9 evaluable patients on the continuous infusion regimen, there was 1 PR. Pharmacokinetic parameters for the bolus regimen at the MTD showed a mean maximum serum concentration (Cmax) of 1,209 +/- 430 ng/mL, with a median T1/2 beta for all courses of 18.2 hours (range, 10.0 to 80.0 hours), a volume of distribution (Vd) of 10.9 L (range, 3.1 to 34.5 L), and a clearance (CL) of 0.45 L/h (range, 0.13 to 2.3 L/h). For the CI regimen at MTD, the mean Cmax was 963 +/- 473 ng/mL, with a median T1/2 beta for all courses of 22.8 hours (range, 24.1 to 30.6 hours), a Vd of 9.4 L (range, 4.4 to 19.5 L), and a CL of 0.32 L/h (range, 0.12 to 0.55 L/h). Twenty-five percent of the patients on the bolus infusion regimen and 30% on the CI regimen made antibody against mouse Ig (HAMA) and/or ricin A chain antibody (HARA). We conclude that this IT can be administered safely and that both regimens achieve comparable peak serum concentrations at the MTD; these concentrations are similar to those achieved previously using other regimens with IgG-dgA ITs at their respective MTDs. Thus, toxicity is related to the serum level of the IT and does not differ with different targeting MoAbs.

Acute graft-versus-host disease (GVHD) is most often treated with high dose glucocorticoids, but less than half of patients have durable overall improvement. Previous phase I and phase II studies suggested that treatment with a CD5-specific immunotoxin (XomaZyme-CD5 Plus) could ameliorate symptoms of GVHD. In a randomized, double-blind trial, we compared XomaZyme-CD5 Plus and glucocorticoids versus placebo and glucocorticoids as initial therapy for 243 patients who developed acute GVHD after allogeneic marrow transplantation. The study drug (XomaZyme. CD5-Plus or an identical appearing placebo) was administered at a dose of 0.1 mg/kg body weight on each of 14 consecutive days. All patients were treated concomitantly with a standard regimen of methylprednisolone. At the time of entry on study, 94% of patients had a rash, 56% had hyperbilirubinemia, 61% had diarrhea, and 84% had nausea and vomiting. At 3, 4, and 5 weeks after starting treatment, symptom severity was less in the CD5 group than in the placebo group. At 4 weeks, 40% of patients assigned to the CD5 group had complete response compared with 25% of those assigned to the control group (P = .019). At 6 weeks, 44% of patients assigned to the CD5 group had complete response as compared with 38% in the placebo group (P = .36). Clinical extensive chronic GVHD developed in 65% of patients in the CD5 group compared with 72% in the control group (P = .35). Survival at 1 year after treatment was 49% in the CD5 group and 45% in the control group (P = .68). Side effects required close monitoring and appropriate adjustment of treatment. The combined administration of a CD5-specific immunotoxin and glucocorticoids controls GVHD manifestations more effectively than treatment with glucocorticoids alone during the first 5 weeks after starting treatment. Use of this immunotoxin does not result in any long-term clinical benefit for patients with acute GVHD.

To reduce the morbidity and mortality associated with unrelated donor bone marrow (BM) transplantation and potentially extend the pool of suitable donors, cryopreserved unrelated donor umbilical cord blood was considered as an alternate source of hematopoietic stem cells for transplantation. Patients with leukemia, BM failure syndrome, or inborn error of metabolism were eligible for a phase I clinical trial designed to estimate the risk of graft failure and severe acute graft-versus-host disease after transplantation of umbilical cord blood from unrelated donors. As of December 21, 1995, unrelated donor umbilical cord blood was used to reconstitute hematopoiesis in eighteen patients aged 0.1 to 21.3 years weighing 3.3 to 78.8 kg with acquired or congenital lympho-hematopoietic disorders or metabolic disease. Patients received either HLA-matched (n = 7) or HLA-1 to 3 antigen disparate (n = 11) grafts collected and evaluated by the New York Blood Center (New York, NY). The probability of engraftment after unrelated donor umbilical cord blood transplantation was 100% with no patient having late graft failure to date. The probability of grade III-IV acute graft-versus-host disease at 100 days was 11%. With a median follow-up of 6 months (range, 1.6 to 17 months); the probability of survival at 6 months is 65% in this high risk patient population. We conclude that cryopreserved umbilical cord blood from HLA-matched and mismatched unrelated donors is a sufficient source of transplantable hematopoietic stem cells with high probability of donor derived engraftment and low risk of refractory severe acute graft-versus-host disease. Limitations with regard to recipient size and degree of donor HLA disparity remain to be determined.

Patients with non-Hodgkin's B-cell lymphoma who received an antitumor vaccine of idiotypic ig protein showed humoral and proliferative immune responses. Because immunity to some antigens, including tumor antigens and human pathogenic viruses, may be better correlated with the cytolytic cellular immune response, we evaluated 16 non-Hodgkin's lymphoma patients immunized with autologous idiotypic ig molecules for changes in tumor-specific cytotoxic T-lymphocyte precursor (CTLp) frequency using limiting dilution analysis. Eleven patients had a significant increase in tumor-specific CTLp. Eight of these 11 patients remain without evidence of disease or with stable minimal disease. In contrast, all five patients who did not have a significant change in tumor-specific CTLp have developed progressive disease. Patient vaccination with tumor associated protein antigens can increase tumor-specific CTLp frequencies. The correlation of increased tumor specific CTLp with freedom from progression is significant at P = .002. This study indicates that measurement of CTLp frequencies are relevant to the clinical evaluation of human tumor vaccines and suggests that cell-mediated cytolytic immune responses may be an important determinant of vaccine efficacy.

Thirty-one patients (median age, 44 years) with advanced hematologic malignancies were given thiotepa 15 mg/kg, and cyclophosphamide 120 (n = 14) or 150 (n = 17) mg/kg followed by unfractionated peripheral blood stem cell transplants (PBSCT) from genotypically identical siblings (n = 28) or one antigen mismatched family donor (n = 3). Donors were mobilized with granulocyte colony-stimulating factor 5 to 10 microgram/kg/d for 6 days and underwent two to three leukapheresis on days +5, +6, +7. The median cell yield per donor expressed/kg of recipients body weight was as follows: nucleated cells 13 x 10(8)/kg; CD34+ cells 6 x 10(6)/kg; colony-forming unit-granulocyte macrophage 38 x 10(4)/kg, and CD3+ cells 449 x 10(6)/kg. The diagnoses were chronic myeloid leukemia (n = 4), acute myeloid (n = 9) or lymphoid leukemia (n = 2), acute myelofibrosis (n = 2), multiple myeloma (n = 1), lymphoma (n = 6), chronic lymphocytic leukemia (n = 1) myelodysplasia (n = 6). Twenty-eight patients had advanced disease, 29 patients were first grafts, and 2 were second transplants 3 and 9 years after the first. Neutrophil counts of 0.5 x 10(9)/L and platelet counts of 30 x 10(9)/L platelets were both achieved on day +14 (median). Engraftment could be proven by sex markers or DNA polymorphism in 29 of 31 patients: one had early leukemia relapse and one patient was unevaluable because of early death. Acute graft-versus-host disease (GVHD) was scored as minimal or absent (grade 0 to 1) in 14 patients, moderate (grade II) in 13, and severe (grade III to IV) in four. Causes of death were leukemia (n = 4), acute GVHD (n = 4, with associated cytomegalovirus infections in three), sepsis (n = 1), liver failure (n = 1), multiorgan failure (n = 1), and hemorrhage (n = 1). The actuarial transplant mortality is 29%, the actuarial relapse rate 22%. Nineteen patients survive with a median follow up of 288 days (100-690). The actuarial 2-year survival is 57%. Three patients received PBSCT from family donors mismatched for one class II antigen: all engrafted, one developed grade I aGVHD; one died of leukemia on day +155; two are alive disease free 267 to 290 days postgraft. This study suggests that thiotepa cyclophosphamide followed by unfractionated PBSC allograft may be an alternative form of transplant for adults with advanced leukemia, also in the setting of one antigen mismatched donor. The engraftment is rapid with acceptable GVHD and relatively low transplant-related mortality.

The diagnosis of idiopathic immune thrombocytopenia remains a clinical diagnosis based on the exclusion of other causes of immune and nonimmune thrombocytopenia. Measurement of platelet-associated Ig (PAIg), while sensitive, is nonspecific for the diagnosis of immune thrombocytopenia. Published experience of antigen capture assays (including monoclonal antibody immobilization of platelet antigens or MAIPA) suggest a high sensitivity and specificity (70% to 80%) in selected groups of patients. In a prospective evaluation of 158 patients with thrombocytopenia from all causes, we report a sensitivity of 51% and specificity of 80% for direct MAIPA assays. MAIPA was considerably better in discriminating immune from nonimmune thrombocytopenia than two assays of PAIgG. Antiplatelet antibodies detected by MAIPA were more frequently directed against the glycoprotein (GP) IIb/IIIa than the GP Ib/IX complex. Our experience suggests that MAIPA assays are useful in the laboratory assessment of thrombocytopenia, should be performed before therapy, and that some patients with 'nonimmune' thrombocytopenia may have genuine antiplatelet antibodies.

In 1994, the Italian and the German Chronic myeloid leukemia (CML) trials comparing interferon-alpha (IFN-alpha) with conventional chemotherapy were published. The survival advantage in favor of IFN-alpha compared with hydroxyurea (HU; 72 v 52 months) was significant in the Italian (P < .002), but not in the German trial (66 v 56 months, P < .44). We set up a collaborative study to identify the reasons for the different outcomes. There are major differences in the trial protocols concerning admission criteria, treatment strategy, and definitions. The German patients were older and more seriously sick. Fifty-two of the 327 patients in the German IFN and HU arms did not fulfil Italian admission criteria, and 41 of the 322 Italian patients did not fulfil German admission criteria. Using mutually uniform admission criteria, the median survival times of the IFN patients are 76 (Italian) and 72 (German) months (P = .56). The Italian group administered IFN combined with HU as needed, whereas the German group strictly used IFN as monotherapy with rerandomization to busulfan (BU) or HU after IFN resistance or intolerability. The differences seen between the Italian and the German trial results can be accounted for by objective differences in study design, especially the admission criteria, treatment strategy, and bias due to intention to treat analysis. The detailed analysis of the data suggests that the combination of IFN with HU as needed is more effective than either agent alone.

In children with acute lymphoblastic leukemia (ALL), the level of minimal residual disease (MRD) at the end of induction strongly predicts outcome, presumably because it measures both drug sensitivity and the number of leukemic cells requiring elimination. Children with high levels (> 10(-3) leukemic cells per marrow cell) nearly always relapse, whereas those with low levels (<2 x 10(-5)) seldom do. However, the importance of MRD in adult ALL is unclear. We studied 27 patients aged 14 to 74 who were treated with a standard protocol and who attained morphological remission. MRD in the marrow at first remission was quantified by using the polymerase chain reaction (PCR), with the rearranged immunoglobulin heavy chain gene as a molecular marker. Levels of MRD varied from 3 x 10(-1) to <7 x 10(-7). The probability of long-term relapse-free survival was significantly related to the level of MRD and only one of nine patients with MRD >10(-3) did not relapse. For patients who did relapse, there was an inverse relationship between MRD level and the length of remission. Overall, MRD in adults in whom a translocation had not been identified was significantly higher than in comparably-treated children, suggesting that ALL in adults is more drug-resistant than in children.

Timed sequencing of cycles of induction chemotherapy in acute myeloid leukemia (AML) has been proposed as a way to achieve maximal leukemic cell kill through recruitment and synchronization of residual neoplastic cells. Furthermore, whether intensive induction therapy should be continued in the presence of profound myelosuppression is an important question. The Children's Cancer Group (CCG) conducted a prospective randomized trial in which 589 patients with AML were randomized at diagnosis to one of two induction approaches involving a 4-day cycle of five active chemotherapeutic agents, with the second cycle administered either 10 days after the first cycle, despite low or dropping blood counts (intensive timing), or 14 days or later from the beginning of the first cycle, depending on bone marrow status (standard timing). All patients achieving remission received a total of four cycles of induction therapy. They were then allocated to allogeneic bone marrow transplantation (BMT) if a compatible family donor was present or randomized to aggressive nonmyeloablative therapy or to myeloablative therapy with purged autologous BMT rescue. The three postremission arms remain coded. Induction success and median days to complete induction were similar for the 295 patients randomized to the intensive timing arm (75%, 99 days) compared with the 294 patients randomized to the standard timing arm (70%, 105 days; P = .18 for remission). However, a marked improvement in outcome was demonstrated in patients randomized to the intensive timing arm, with an actuarial event-free survival at 3 years of 42% +/- 7% (95% confidence interval [CI]) versus 27% +/- 6% for patients on the standard timing arm (P = .0005). Disease-free survival results at 3 years from the end of induction were superior for patients receiving intensively timed induction therapy (N = 211), 55% +/- 9% versus 37% +/- 9% for standard timing patients (N = 195, P = .0002), with a median follow-up from achieving remission of 28 months. Superior results were documented for patients receiving intensive timing irrespective of the postremission therapy to which they were allocated. Intensively timed induction therapy for patients with AML markedly improves event-free survival, even for patients undergoing myeloablative therapy with BMT rescue. Without controlling for the type of induction therapy received, results of various BMT studies in AML comparing different preparative regimens will be difficult to interpret.

Pluripotent stem cells of hematopoiesis and lymphopoiesis are among the CD34+ cells in blood or bone marrow. After granulocyte-colony stimulating factor (G-CSF) treatment, 1% to 2% of the mononuclear cells in blood are CD34+ cells, which can be procured by leukapheresis. We investigated the potential of CD34+ blood cells for reconstituting hematopoiesis and lymphopoiesis after allogeneic transplantation. HLA-identical sibling donors of 10 patients with hematologic malignancies were treated with G-CSF (filgrastim), 5 microgram/kg subcutaneously twice daily for 5 to 7 days. CD34+ cells were selected from the apheresis concentrates by immunoadsorption, concomitantly the number of T cells was reduced 100- to 1,000-fold. After transplantation, five patients received cyclosporine A for graft-versus-host disease (GvHD) prophylaxis (group I); five patients additionally received methotrexate (group II). G-CSF and erythropoietin were given to all patients. Mean numbers of 7.45 x 10(6) CD34+ and 1.2 x 10(6) CD3+ cells per kilogram were transplanted. In group I, the median times of neutrophil recovery to 100, 500, and 1,000 per mm3 were 10, 10, and 11 days, respectively. Group II patients reached these neutrophil levels after 10, 14, and 15 days, respectively. Platelet transfusions were administered for a median of 18 days in group I and 30 days in group II, and red blood cells for 9 and 12 days, respectively. Between day 30 and 60, lymphocytes reached levels of 353 +/- 269 cells per mm3. The median grades of acute GvHD were III in group I and I in group II. Two patients in group I died from acute GvHD. Two leukemic relapses occurred in group II. Complete and stable donor hematopoiesis was shown in all patients with a median follow up of 370 (45 to 481) days. Allogeneic blood CD34+ cells can successfully reconstitute hematopoiesis and lymphopoiesis. Reduction of T cells by CD34+ blood cell enrichment and cyclosporine A alone might not be sufficient for prophylaxis of severe acute GvHD.

Long-term survival and improved neuropsychological function have occurred in selected children with Hurler syndrome (MPS I H) after successful engraftment with genotypically matched sibling bone marrow transplantation (BMT). However, because few children have HLA-identical siblings, the feasibility of unrelated donor (URD) BMT as a vehicle for adoptive enzyme therapy was evaluated in this retrospective study. Forty consecutive children (median, 1.7 years; range, 0.9 to 3.2 years) with MPS I H received high-dose chemotherapy with or without radiation followed by BMT between January 27, 1989 and May 13, 1994. Twenty-five of the 40 patients initially engrafted. An estimated 49% of patients are alive at 2 years, 63% alloengrafted and 37% autoengrafted. The probability of grade II to IV acute graft-versus-host disease (GVHD) was 30%, and the probability of extensive chronic GVHD was 18%. Eleven patients received a second URD BMT because of graft rejection or failure. Of the 20 survivors, 13 children have complete donor engraftment, two children have mixed chimeric grafts, and five children have autologous marrow recovery. The BM cell dose was correlated with both donor engraftment and survival. Thirteen of 27 evaluable patients were engrafted at 1 year following URD BMT. Neither T-lymphocyte depletion (TLD) of the bone marrow nor irradiation appeared to influence the likelihood of engraftment. Ten of 16 patients alive at 1 year who received a BM cell dose greater than or equal to 3.5 x 10(8) cells/kg engrafted, and 62% are estimated to be alive at 3 years. In contrast, only 3 of 11 patients receiving less than 3.5 x 10(8) cells/kg engrafted, and 24% are estimated to be alive at 3 years (P = .05). The mental developmental index (MDI) was assessed before BMT. Both baseline and post-BMT neuropsychological data were available for 11 engrafted survivors. Eight children with a baseline MDI greater than 70 have undergone URD BMT (median age, 1.5 years; range, 1.0 to 2.4 years). Of these, two children have had BMT too recently for developmental follow-up. Of the remaining six, none has shown any decline in age equivalent scores. Four children are acquiring skills at a pace equal to or slightly below their same age peers; two children have shown a plateau in learning or extreme slowing in their learning process. For children with a baseline MDI less than 70 (median age, 2.5 years; range, 0.9 to 2.9 years), post-BMT follow-up indicated that two children have shown deterioration in their developmental skills. The remaining three children are maintaining their skills and are adding to them at a highly variable rate. We conclude that MPS I H patients with a baseline MDI greater than 70 who are engrafted survivors following URD BMT can achieve a favorable long-term outcome and improved cognitive function. Future protocols must address the high risk of graft rejection or failure and the impact of GVHD in this patient population.

In the Working Formulation (WF), non-Hodgkin's lymphomas (NHL) are grouped according to their clinical behavior. These disorders are listed as entities defined by morphology, phenotype, and cytogenetics in the proposed Revised European-American Classification of Lymphoid Neoplasms (REAL), the clinical relevance of which is still debated. We analyzed 670 NHL cases included in two randomized clinical trials (EORTC 20855 WF-intermediate/high-grade and 20856 WF-low-grade malignancy) with histologic material available for review. Based on hematoxylin-eosin-stained sections, 77% of cases could be subtyped. Immunophenotyping was considered to be mandatory only in diagnosing T-cell lymphoma and anaplastic large-cell lymphoma. Of 522 cases subtyped, 11% were mantle cell lymphoma (MCL), 5% were marginal zone B-cell lymphoma (MZBCL), 46% were follicle center lymphoma, and 32% were diffuse large B-cell lymphoma. Statistical analysis and comparisons between classifications were made only within each trial and treatment group. MCL and MZBCL were characterized by a shorter median survival (3.4 and 4.1 years, respectively) in comparison with low- and intermediate-grade WF groups (> 9.3 and 5.8 years, respectively). In terms of progression-free survival, MCL showed a behavior similar to the low-grade group, with frequent relapses. Follicle center cell lymphomas behaved as low-grade lymphomas as defined by the WF and diffuse large B-cell lymphomas as the WF-intermediate grade group. Because several NHL entities have a clinical behavior of their own, their recognition by the REAL classification offers clinicians additional information that is not obtained when the WF is used.

Patients with myelodysplastic syndromes (MDS) have refractory cytopenias leading to transfusion requirements and infectious complications. In vitro marrow culture data have indicated that granulocyte colony stimulating factor (G-CSF) synergizes with erythropoietin (EPO) for the production of erythroid precursors. In an effort to treat the anemia and neutropenia in this disorder, MDS patients were treated with a combination of recombinant human EPO and recombinant human G-CSF. Fifty-five patients were enrolled in the study of which 53 (96%) had a neutrophil response. Forty-four patients were evaluable for an erythroid response of which 21 (48%) responded. An erythroid response was significantly more likely in those patients with relatively low serum EPO levels, higher absolute basal reticulocyte counts and normal cytogenetics at study entry. Seventeen (81%) of the patients who responded to combined G-CSF plus EPO therapy continued to respond during an 8-week maintenance phase. G-CSF was then discontinued and all patients' neutrophil responses were diminished, whereas 8 continued to have an erythroid response to EPO alone. In 7 of the remaining 9 patients, resumption of G-CSF was required for recurrent erythroid responses. The median duration of erythroid responses to these cytokines was 11 months, with 6 patients having relatively prolonged and durable responses for 15 to 36 months. Our results also indicate that approximately one half of responding patients require both G-CSF and EPO to maintain an effective erythroid response, suggesting that synergy between G-CSF and EPO exists in vivo for the production of red blood cells in MDS.

Interferon (IFN) is effective in treating adults as well as children with chronic hepatitis C. We investigated the efficacy of IFN therapy in 13 children with underlying acute leukemia who had chronic hepatitis C (age range, 5 to 17 years; mean age, 9.9 years). Natural IFN- alpha was administered at a dose of 0.1 mega unit (MU)/kg (maximum dose, 6.0 MU) daily for 2 weeks and then three times per week for an additional 22 weeks (total dose, 8 MU/kg). IFN treatment was initiated at least 2 years after the completion of treatment for acute leukemia. A complete response was obtained in 5 children (38%). The serum level of anti-hepatitis C virus core antibody was closely related to the response to IFN. IFN therapy was well tolerated by all but 1 of the children, who developed mild transient heart failure 4 months after the initiation of therapy. IFN therapy for children with chronic hepatitis C who had underlying acute leukemia was beneficial. However, further trials are required to confirm the safety and improve the dosage schedule of IFN therapy.

We administered liposome-encapsulated all-trans retinoic acid (L-ATRA) to 48 patients with refractory hematologic malignancies using an every-other-day schedule for 28 days and doses of 15 to 175 mg/m2. In 19 patients, pharmacology studies were conducted after the first (day 1) and seventh (day 15) doses. In contrast to the decline in tretinoin concentration seen within 3 to 4 days of administration of daily oral ATRA, there were no differences between the area under the curve (AUC) of tretinoin concentration versus time on day 1 and day 15 (P = .98, Wilcoxon signed-rank test). Peak day 1 concentrations after 15 mg/m2 were higher than those reported after 45 mg/m2 oral ATRA. Six patients with relapsed acute promyelocytic leukemia (APL) were treated. Three, each in first relapse and at least year from the last exposure to oral ATRA, achieved a complete response (CR). Disease recurred in two (one at 3 months despite maintenance L-ATRA and similarity in tretinoin AUC on days 1 and 85, and the other at 5 months, 2 months after discontinuation of L-ATRA) and the third was transplanted 1 month into CR. The three nonresponders were in at least a second relapse and failed to respond to oral ATRA before or immediately after receiving L-ATRA. Severe toxicity developed in three of eight patients treated at 175 mg/m2 (joint pains in two, skin in one). The maximum tolerated dose (MTD) was determined to be 140 mg/m2, at which dose grade 2 toxicity (primarily headache and skin) occurred in eight of eight patients, but grade 3 to 4 toxicity in none. Compared with oral ATRA, L-ATRA apparently results in greater exposure to tretinoin and for a longer time.

We performed a phase I trial of recombinant human interleukin-11 (rhIL-11) in women with breast cancer. Cohorts of three to five women were accrued to five dosage levels of rhIL-11 (10, 25, 50, 75, and 100 micrograms/kg/d). rhIL-11 alone was administered by a daily subcutaneous injection for 14 days during a 28-day prechemotherapy "cycle 0." Patients (pts) subsequently received up to four 28-day cycles of cyclophosphamide (1,500 mg/m2) and doxorubicin (60 mg/m2) chemotherapy followed by rhIL-11 at their assigned dose (days 3 through 14). Sixteen pts (13 stage IV, 3 stage IIIB) were accrued to this study. Median age was 53 years and median Eastern Cooperative Oncology Group Performance Status was 0. A grade 3 neurologic event was seen in 1 pt at 100 micrograms/kg. Because of the degree of grade 2 constitutional symptoms (myalgias/arthralgias and fatigue) at 75 micrograms/kg, dose escalation was stopped and 75 micrograms/kg was the maximally tolerated dose. No other grade 3 or 4 adverse events related to rhIL-11 were seen. The administration of rhIL-11 was not associated with fever. Reversible grade 2 fatigue and myalgias/arthralgias were seen in all pts at 75 micrograms/kg. Weight gain of 3% to 5% associated with edema was seen at doses > 10 micrograms/kg but a capillary leak syndrome was not seen. rhIL-11 alone was associated with a mean 76%, 93%, 108%, and 185% increase in platelet counts at doses of 10, 25, 50, and 75 micrograms/kg, respectively. No significant changes in leukocytes were seen. A mean 19% decrease in hematocrit was observed. Acute-phase proteins increased with treatment at all doses. Compared with patients at the 10 micrograms/kg dose, patients receiving doses > or = 25 micrograms/kg experienced less thrombocytopenia in the first two cycles of chemotherapy. We conclude that rhIL-11 has thrombopoietic activity at all doses studied, is well tolerated at doses of 10, 25, and 50 micrograms/kg, and at doses > or = 25 micrograms/kg has the potential to reduce chemotherapy-induced thrombocytopenia in this model.

Thrombocytopenia is a complication of cancer treatment that can limit dose intensity. Interleukin-11 (IL-11) is a growth factor that increases platelet production. We conducted a multicenter, randomized, placebo-controlled trial of recombinant human IL-11 (rhIL-11) in 93 patients with cancer who had already been transfused platelets for severe thrombocytopenia resulting from chemotherapy. The patients had received platelet transfusions for nadir platelet counts of < or = 20,000/microL during the chemotherapy cycle immediately preceding study entry. Chemotherapy was continued during the study without dose reduction. Patients were randomized to receive placebo or rhIL-11 at 50 or 25 micrograms/kg subcutaneously once daily for 14 to 21 days beginning 1 day after chemotherapy. Eight of 27 (30%) evaluable patients treated with rhIL-11 at a dose of 50 micrograms/kg did not require platelet transfusions versus 1 of 27 (4%) patients who received placebo (P < .05). Five of 23 (18%) patients treated with rhIL-11 at 25 micrograms/kg avoided platelet transfusions (P = .23). Side effects were fatigue and cardiovascular symptoms, including a low incidence of atrial arrhythmias and syncope. There were no differences among treatment groups in the incidence of neutropenic fever, days of hospitalization, or number of red blood cell transfusions. This study shows that rhIL-11 treatment of a dose of 50 micrograms/kg significantly increases the likelihood that patients who have already been transfused platelets for severe chemotherapy-induced thrombocytopenia will not require platelet transfusions during a subsequent chemotherapy cycle.

FK506 (Tacrolimus) is an immunosuppressive drug that blocks the activation of antigen-specific T lymphocytes, a major component in the pathogenesis of graft-versus-host disease (GVHD). This study was designed to obtain first estimates of the safety and efficacy of FK506 monotherapy in the prevention of GVHD following HLA-identical sibling marrow transplantation. Additionally, a subset of patients was studied to define the pharmacokinetic profile of FK506. Twenty-seven adult patients with leukemia or myelodysplasia received FK506 starting the day before transplant at a dose of 0.04 mg/kg/d by continuous intravenous infusion. When clinically possible, FK506 was given orally in two divided doses starting at five times the daily intravenous dose. FK506 doses were adjusted to target a steady state or trough blood level between 10 to 30 ng/mL. These patients were followed for 6 months posttransplant. All patients had sustained marrow engraftment. Frequently noted adverse events included reversible renal dysfunction, diarrhea, fever, nausea, vomiting, and headache. Most patients required FK506 dose reductions associated with elevated serum creatinine. Two (7%) patients relapsed, one of whom died of the disease within the 6-month study period. A second patient died due to pulmonary mucor. Whole blood pharmacokinetic parameters indicated a half-life of 18.2 +/- 12.1 hours; volume of distribution of 1.67 +/- 1.02 L/kg; clearance of 71 +/- 34 mL/h/kg; and bioavailability of 32 +/- 24%. Eleven of 27 (41%) patients developed grade II to IV acute GVHD, including 10 grade II and one grade III. Six of 24 (25%) evaluable patients developed chronic GVHD. These data indicate that FK506 monotherapy has activity in preventing GVHD. Further studies of FK506 with lower doses to improve tolerability and in combination with other immunosuppressants to augment efficacy are warranted.