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Biomedical subjects

M J Keating

Publications and source records attributed to M J Keating.

At least 19 recordsLinked to original sources

A topographic representation of auditory space in the external nucleus of the inferior colliculus of the guinea-pig.

The possibility that the external nucleus of the inferior colliculus (ICX) of the pigmented guinea-pig contains a map of auditory space has been investigated. Auditory stimuli consisted of broad-band sound delivered under free-field anechoic conditions from a range of positions around the animal's azimuthal axis. The responses of clusters of neurons in the ICX to threshold and to near-threshold stimuli displayed sharp spatial tuning. The responses recorded from rostral ICX revealed a preference for auditory stimuli in the anterior field while more caudal neurons preferentially responded to sounds presented in the posterior field. Neurons at intermediate points, along the rostro-caudal axis of the nucleus, displayed preferences for sound stimuli in appropriately intermediate field positions along the contralateral azimuthal axis. At higher stimulus intensities the spatial tuning of the responses decreased, but the optimal direction of preference was usually retained. The contribution of binaural processing to auditory spatial tuning was evident, since unilateral cochlea ablation destroyed the spatial tuning at higher stimulus intensities. The results presented provide the first evidence that a topographically ordered representation of the contralateral auditory azimuth is present in the ICX of a mammal.

Acoustic Stimulation

Response assessment in chronic lymphocytic leukemia after fludarabine plus prednisone: clinical, pathologic, immunophenotypic, and molecular analysis.

The goals of this study were to evaluate the response to treatment in chronic lymphocytic leukemia (CLL) according to clinical, pathologic, immunophenotypic, and molecular features, as well as to address the clinical significance of each finding. One hundred fifty-nine CLL patients with either advanced Rai stage III or IV (81 patients) or progressive Rai stage 0 to II (78 patients) were treated with fludarabine (30 mg/m2/d intravenously every day for 5 days) plus prednisone (30 mg/m2/d orally daily for 5 days). Thirty-six patients were previously untreated. The response rates were 12% complete response (CR), 30% nodular complete response (nCR), and 18% partial response (PR). In all patients who achieved a complete response (both CR and nCR) less than 30% of nucleated cells were lymphocytes on marrow aspirate differential analysis; however, nCR patients had residual nodular and/or interstitial lymphocyte involvement on marrow biopsy examination. There was no evidence of leukemic infiltration on marrow biopsy examination in CR patients. With a median follow-up of 35 months, comparison of time to progression in the CR and nCR groups at 2 years showed a projected 87% versus 55% progression-free survival (P less than .03). Residual disease assessment by flow cytometry using simultaneous dual-color staining on blood and marrow lymphocytes was also performed on each patient. Residual disease was determined by the expression of CD5 on B lymphocytes and the monoclonality of surface light-chain expression. After six courses of fludarabine plus prednisone, no residual disease was detected by flow cytometry in 89% of the CRs, 51% of the nCRs, and 19% of the PRs. Clinical residual disease in PR patients with no residual disease detectable by flow cytometry was limited to lymph-adenopathy. Time to progression at 2 years was longer in CR and nCR patients having no residual disease detected by flow cytometry (84% v 39% 2-year progression-free survival, P less than .001). Posttreatment lg gene rearrangement analysis using JH, J kappa, and C lambda probes demonstrated no rearranged bands and a return to the germline configuration in five of seven CRs and two of eight nCRs studied. The molecular studies were concordant with the dual-parameter immunophenotype results and none of the patients who reverted to a germline DNA pattern after treatment have experienced relapse. The absence of detectable minimal residual disease by bone marrow biopsy, dual-color flow cytometry, and lg gene rearrangement analysis is achieveable in CLL with fludarabine and is predictive of the response duration.

Adult

Treatment of hairy cell leukemia with 2-chlorodeoxyadenosine (2-CdA).

We administered one course of 2-chlorodeoxyadenosine (2CdA) at 4 mg/m2 daily for 7 days by continuous intravenous infusion to 46 patients with hairy cell leukemia. Complete remissions occurred in 36 patients (78%; 95% confidence limits, 63% to 89%), partial remissions in five (11%), and a minor response in one. One patient died of candida sepsis 3 weeks after beginning treatment and three patients were clearly resistant to therapy. These three either had morphologically atypical hairy cells, less than 20% of which expressed Ig light chain on the cell surface, or had failed prior treatment with deoxycoformycin and interferon-alpha. At a median of 37 weeks since discontinuation of therapy, recurrent thrombocytopenia has developed in one patient, whose marrow remains normal, while a bone marrow relapse has occurred in another patient, whose blood counts remain normal. Treatment produced a greater than 50% decrease in neutrophil count in 26 patients, which lasted 3 to 4 weeks and was associated with an increased incidence of febrile episodes. These episodes occurred in 21 patients but were associated with documented infection in only four patients. Decreases in the number of CD4+ lymphocytes appeared to occur regularly after treatment and have persisted for a median of 18 weeks without obvious clinical significance. Although years of follow-up will be needed, our results confirm Piro et al's observation (N Engl J Med 322: 1117, 1990) that 2CdA appears to be highly effective in the treatment of hairy cell leukemia.

2-Chloroadenosine

Intensive chemotherapy with mitoxantrone and high-dose cytosine arabinoside followed by granulocyte-macrophage colony-stimulating factor in the treatment of patients with acute lymphocytic leukemia.

Thirty-four adults with refractory acute lymphocytic leukemia received salvage therapy with mitoxantrone 5 mg/m2 intravenously over 1 hour daily for 5 days and cytosine arabinoside (ara-C) 3 g/m2 intravenously over 2 hours every 12 hours for six doses, followed by granulocyte-macrophage colony-stimulating factor (GM-CSF) 125 microgram/m2 intravenously over 4 hours daily until recovery of granulocytes above 2.0 x 10(3)/microL. Their outcome was compared with 29 prognostically similar historical control patients treated with the identical chemotherapy without GM-CSF. Overall, the complete response rates were similar in the treatment and control groups (13 of 34 [38%] v 11 of 29 [38%]). There was a trend for less remission induction mortality in the GM-CSF-treated patients (2 of 34 [6%] v 6 of 29 [21%]; P = .08), but, conversely, a higher rate of resistant disease (19 of 34 [56%] v 10 of 29 [34%]; P = .09). Recovery of granulocyte counts above 500/microL was significantly faster in the GM-CSF-treated group (25 days v 33 days; P less than .01), but there was no reduction in the incidence of febrile episodes (91% v 93%) or of documented infections (59% v 59%). Survival was prolonged in the GM-CSF-treated patients but was not of clinical relevance (31 v 20 weeks; P = .05). In summary, the addition of GM-CSF to intensive chemotherapy in refractory adult ALL was associated with a reduction in the remission induction mortality, probably secondary to a shorter duration of granulocytopenia, but not with an improvement in complete response rates.

Adult

Fludarabine infusion potentiates arabinosylcytosine metabolism in lymphocytes of patients with chronic lymphocytic leukemia.

Our previous work has shown that incubation of K562 cells or lymphocytes from patients with advanced chronic lymphocytic leukemia (CLL) with arabinosyl-2-fluoroadenine (F-ara-A) potentiates the rate of arabinosylcytosine 5'-triphosphate (ara-CTP) synthesis during subsequent treatment with arabinosylcytosine (ara-C). To test the biochemical modulation of ara-CTP in a clinical setting, we designed a protocol to administer fludarabine (Fludara, F-ara-AMP) and ara-C in a pharmacologically directed sequence for patients with CLL refractory to conventional fludarabine therapy. ara-C was infused in seven patients with progressive CLL at a dose rate that maximizes ara-CTP accumulation (0.5 g/m2 during 2 h). Fludarabine (30 mg/m2 during 30 min) was infused 20 h later, followed by a second, identical dose of ara-C at 24 h, when the concentration of F-ara-A 5'-triphosphate (F-ara-ATP) was maximal in CLL cells. Comparison of ara-CTP pharmacokinetics in circulating CLL cells demonstrated that the ara-CTP area under the curve increased by a median of 1.5-fold (range, 1.1- to 1.7-fold) after fludarabine infusion. Plasma pharmacokinetics indicated that neither the median steady-state ara-C concentrations nor the levels of its deamination product arabinosyluracil were significantly affected by fludarabine infusion. The median rate of ara-CTP elimination was slightly faster after fludarabine treatment (t1/2, 6.7 versus 5.8 h), suggesting that catabolism of ara-CTP was not responsible for the increased ara-CTP area under the curve. The rate of ara-CTP accumulation by CLL cells after fludarabine infusion, however, was increased by a median of 1.3-fold in seven of the eight patients (range, 1.2- to 1.8-fold); the peak occurred within 1 h of the end of the infusion. In vitro incubation of leukemic lymphocytes with F-ara-A before ara-C also showed a median 1.3-fold increase in the rate of ara-CTP accumulation. Thus, infusion of fludarabine before ara-C augments ara-CTP metabolism in leukemic lymphocytes. This knowledge should be considered in the design of combination chemotherapy.

Antineoplastic Agents

Changing patterns of binocular visual connections in the intertectal system during development of the frog, Xenopus laevis. III. Modifications following early eye rotation.

In the frog, Xenopus laevis, a system of intertectal connections underlies the visual projection from an eye to its ipsilateral tectal lobe and is involved in the topographic representation of binocular visual space. Rotation of one eye in early life may be followed by a radical rearrangement of the connections in this system. The modified pattern which later emerges is that which keeps the visual projection through the ipsilateral eye in topographic registration with the direct visual projection from the contralateral eye to the same tectal lobe. This plasticity requires visual experience. In this paper we describe the time-course and sequence of events by which this plasticity is effected. Following rotation of one eye in larval animals or in animals undergoing metamorphic climax, the earliest evidence of intertectal modification was found 3-4 weeks after metamorphosis. With increasing intervals after metamorphosis an increasing proportion of animals displayed modified intertectal systems. At intermediate intervals many animals showed partial modifications, which were interpreted as transitional stages in the modification process. Analysis of these transitional stages indicated that the sequence of events involved in the elaboration of a modified intertectal system following the experimental alteration of eye alignment exhibits features in common with rearrangements of the system that occur during normal development in response to growth-related alterations in eye alignment.

Animals

Plasticity of binocular visual connections in the frog, Xenopus laevis: reversibility of effects of early visual deprivation.

In frogs, each lobe of the midbrain optic tectum receives two spatially aligned maps of binocular visual space, one through each eye. The map from the contralateral eye is the product of direct retinal input to the tectum, while that from the ipsilateral eye is mediated by a commissural system of connections that relays binocular visual information from one tectal lobe to the other. In Xenopus laevis, dark-reared from early life, the visuotectal map through the ipsilateral eye exhibits significant signs of disorder indicating that the normal development of the underlying "intertectal" system involves experience-dependent processes. Here we investigate the potential of this system for recovery from such deprivation-induced disruption. Three groups of animals were first dark-reared from embryonic stages until 3 months, 12 months or 2 years after metamorphosis. These short-, medium- and long-term periods of visual deprivation are associated with a progressive disturbance of the intertectal system (Grant and Keating 1989b). The animals then experienced 12-18 months in a normal visual environment, before an electrophysiological mapping experiment was carried out to reveal the status of their intertectal system. Quantitative analyses of the visuotopic order in the ipsilateral visuotectal map and of its spatial alignment with the map derived from the contralateral eye revealed that these features were completely normal in all 3 experimental groups. It is concluded that defects present in the intertectal system of dark-reared Xenopus can be repaired by subsequent visual experience, and that the reparative capacity is not limited either by the animal's age or by the existing degree of prior disruption.

Animals

Prognostic significance of elevated serum beta 2-microglobulin levels in adult acute lymphocytic leukemia.

PURPOSE: Elevated serum beta-2 microglobulin (beta 2M) levels are associated with poor prognosis in several lymphoproliferative disorders including multiple myeloma and lymphoma. Their prognostic relevance in acute lymphocytic leukemia (ALL) is unknown. We analyzed the associations of serum beta 2M levels at diagnosis with pretreatment characteristics and with prognosis in adult ALL. PATIENTS AND METHODS: One hundred fifty-nine adults with newly diagnosed ALL were investigated. Serum beta 2M levels were determined at diagnosis, on fresh peripheral blood samples, using a radioimmunoassay, the Pharmacia beta 2 Micro RIA (Pharmacia Diagnostics, Uppsala, Sweden). Statistical correlations were assessed by standard methods, and further independent prognostic value of serum beta 2M was determined by multivariate analysis. RESULTS: Patients with beta 2M levels of 4.0 mg/L or above had a lower complete response rate (61% versus 80%; p = 0.02), a significantly worse survival (p < 0.01), and a significantly higher association with development of central nervous system (CNS) leukemia (p < 0.01). High beta 2M levels were more common among patients with older age, with elevated creatinine, bilirubin, and alkaline phosphatase levels, with low albumin levels, and with B-cell disease. Multivariate analysis for survival indicated the beta 2M level to be an independent prognostic variable (after adjusting for pretreatment creatinine level and age). The evaluation of beta 2M levels within low- and high-risk groups for CNS disease suggested an association of elevated beta 2M levels with a worse incidence of CNS disease in the high-risk patients. CONCLUSION: Monitoring serum beta 2M levels may provide significant prognostic information in adults with ALL and should be included in their pretreatment evaluation. Its importance in childhood ALL requires investigation.

Adult

Orofacial fungal infections. Nine pathogens that may invade during chemotherapy.

Immunosuppression due to antineoplastic drugs or malignant tumor leaves patients extremely vulnerable to infection. Opportunistic fungi that rarely infect healthy persons can have very severe consequences in these patients. Candida albicans is the pathogen found most often, but several other Candida species may cause infection as well. Aspergillosis is the second most frequently seen fungal infection of the face and mouth in patients receiving chemotherapy. Less commonly seen but equally dangerous are infections with Torulopsis glabrata, Mucor, Absidia, Rhizopus oryzae, Histoplasma capsulatum, Cryptococcus neoformans, Coccidioides immitis, Fusarium species, and Trichosporon cutaneum. Restoration of impaired host defenses and use of nystatin (Mycostatin, Nilstat, O-V Statin), clotrimazole (Mycelex), amphotericin B (Fungizone Intravenous), and flucytosine (Ancobon) when appropriate are methods of control.

Antineoplastic Agents

Treatment of chronic myelogenous leukemia in accelerated and blastic phases with daunorubicin, high-dose cytarabine, and granulocyte-macrophage colony-stimulating factor.

PURPOSE: The study was undertaken to improve the results of intensive chemotherapy in chronic myelogenous leukemia (CML) in accelerated (CML-AP) and blastic phases (CML-BP) by the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) as supportive therapy. PATIENTS AND METHODS: Forty-eight patients were treated with daunorubicin 120 mg/m2 intravenously on day 1, cytarabine (ara-C) 1.5 g/m2/d by continuous infusion over 24 hours for 4 days, and Solu-Medrol (methylprednisolone; The Upjohn Co, Kalamazoo, MI) 100 mg/d for 5 days, followed on day 5 by GM-CSF 125 micrograms/m2/d over 6 hours until recovery of granulocyte count above 2.0 x 10(3)/microliters. Twenty-four patients had CML-BP, and 24 had CML-AP. RESULTS: During remission induction, 45 patients (94%) developed febrile episodes (fever of unknown origin, 23 patients [48%]; documented infections, 22 patients [46%]). The median time to recovery of granulocyte count above 0.5 x 10(3)/microliters was 29 days and to platelet count above 30 x 10(3)/microliters, 28 days. Overall, 14 of 48 patients (29%) achieved a complete hematologic remission (CHR), and seven (15%) reverted to a second chronic phase. CHR was noted in eight of 24 patients with CML-BP (33%), and in six of 24 patients with CML-AP (25%). Cytogenetic responses were observed in 11 patients (23%), but were transient. Sixteen patients developed either fluid retention, hypotension, pleuropericardial effusions, or pericarditis, or a combination of these side effects. These side effects were severe in four patients and are likely to be disease-associated, as a similar regimen of intensive chemotherapy and GM-CSF at the same dose and schedule in acute lymphocytic leukemia was not associated with these side effects. CONCLUSIONS: The results pertinent to remission rates, induction mortality, myelosuppression profile and related complications, and overall survival were not significantly improved compared with previous experience. In summary, the results of intensive chemotherapy in CML-transformed phases remain poor, despite the addition of GM-CSF as a supportive measure.

Adult

Treatment of advanced stages of Philadelphia chromosome-positive chronic myelogenous leukemia with interferon-alpha and low-dose cytarabine.

PURPOSE: To evaluate the efficacy of interferon-alpha (IFN-A) and low-dose cytarabine (ara-C) combination chemotherapy in patients with chronic myelogenous leukemia (CML). PATIENTS AND METHODS: Sixty patients with advanced phases of Philadelphia chromosome (Ph)-positive CML received combination therapy with IFN-A 5 x 10(6) U/m2 daily, and low-dose ara-C 15 mg/m2 daily for 2 weeks every 4 weeks until remission, then for 1 week every month as maintenance. Forty patients were in late chronic-phase CML, and 20 were in accelerated-phase CML (16 with clonal evolution only, four with other criteria). Their outcome was compared with 58 patients (39 late chronic-phase CML and 19 accelerated-phase CML) who had been previously treated with IFN-A alone in the same dose schedule. RESULTS: In late chronic-phase CML, patients receiving IFN-A plus ara-C had a better complete hematologic response (CHR) rate compared with those treated with IFN-A alone (55% v 28%; P = .02), a trend for better Ph suppression (15% v 5%; P = .13), and a longer survival (3-year survival rate 75% v 48%; P less than .01). These differences do not seem to be caused by imbalances in prognostic factors between the two treatment groups. In accelerated-phase CML, the addition of ara-C to IFN-A did not improve the response rate of treated patients, and the difference in survival was accounted for by different patient characteristics. Suppression of clonal evolution was observed in five patients (25%). Patients with clonal evolution as the only criterion for disease acceleration had a longer survival than those with other or additional accelerated-phase criteria (3-year survival rate 67% v 22%; P less than .01). CONCLUSION: The results with the combination of IFN-A plus ara-C in late chronic-phase CML are encouraging, and suggest the need for its evaluation in early chronic-phase CML.

Adult

Phase II trial of fludarabine phosphate in lymphoma: an effective new agent in low-grade lymphoma.

PURPOSE: In a phase II trial we investigated fludarabine phosphate (FAMP) as therapy for patients with relapsed lymphoma to determine its effectiveness and toxicity in this disease. PATIENTS AND METHODS: The 67 assessable patients had a median age of 56 years and had received a median of three chemotherapy regimens before treatment with FAMP. The starting dose was 25 mg/m2 administered intravenously over 30 minutes daily for 5 days every 3 to 4 weeks. RESULTS: High response rates were observed for follicular small cleaved-cell lymphoma (FSCCL) (62%), follicular mixed small- and large-cell lymphoma (80%), and follicular large-cell lymphoma (FLCL) (100%). Responses also occurred in small lymphocytic lymphoma (SLL) (33%), transformed lymphoma (33%), mycosis fungoides (40%), and Hodgkin's disease (25%). No responses were observed in other intermediate- or high-grade lymphomas (N = 20). Overall, there were five patients with a complete response, 23 patients with a partial response, and an overall response rate of 37%. Toxicity was primarily hematologic and infectious. No significant gastrointestinal, hepatic, renal, or neurologic toxicity occurred. CONCLUSIONS: We conclude that FAMP has major activity in follicular lymphoma. Fundamental research is needed to understand this differential efficacy in low-grade lymphoma yet lack of efficacy in intermediate- and high-grade lymphoma. Clinical investigations should be done using FAMP in varying dose schedules and in combination regimens.

Adult

Cytogenetics for detection of minimal residual disease in acute myeloblastic leukemia.

Bone marrow samples collected from acute myeloblastic leukemia (AML) patients in complete clinical and hematological remission were studied for the persistence of cytogenetic abnormalities. AML patients from the three favorable cytogenetic categories [inv 16, t(8;21) and t(15;17)] and patients from the unfavorable cytogenetic categories (+8, -5, -7 and Philadelphia-positive) were studied. Seventy-one patients had evaluable metaphase spreads in remission marrows and 20 (28%) had one or more abnormal metaphases identical to that present in the pretreatment marrow. All 20 of these patients relapsed within 78 weeks, thus there were no false positive studies. Fifty-one patients had only diploid metaphases in their complete remission marrow, 25 relapsed, and 21 remained in continuous complete remission. Thus there was a 49% false negative rate of this study. These data indicate that the failure to detect residual chromosomally abnormal cells in the bone marrow does not guarantee continuous complete remission. Cytogenetic study was most useful in the favorable cytogenetic groups and least useful in the unfavorable groups. The persistence of normal metaphases in pretreatment marrows did not affect outcome or risk of recurrence. Twenty-five of 34 evaluable patients who relapsed after remission had either the identical cytogenetic abnormality present in the pretreatment marrow or showed the identical abnormality with additional chromosomal changes. Thus study indicates that cytogenetic examinations of complete remission bone marrow samples in patients with AML provides an objective method for detecting residual leukemia, and identifies patients with a potential for prolonged disease-free survival.

Bone Marrow

A comparison of imipenem to ceftazidime with or without amikacin as empiric therapy in febrile neutropenic patients.

BACKGROUND: Neutropenic patients with cancer are traditionally treated with empiric antibiotic combinations when they become febrile. The availability of broad-spectrum antibiotics such as ceftazidime and imipenem has made it possible to initiate therapy with a single agent (monotherapy). The objectives of this trial were to compare ceftazidime and imipenem as single agents for the therapy of febrile episodes in neutropenic patients and to ascertain whether the addition of an aminoglycoside (amikacin) to either of these agents would provide an advantage. METHODS: A prospective clinical trial was conducted in which eligible neutropenic patients with cancer were randomized to one of four treatment arms: ceftazidime alone; imipenem alone; ceftazidime plus amikacin; and imipenem plus amikacin. Efficacy analysis was done for 750 assessable episodes. A multivariate logistic-regression analysis was also performed to examine the unique contribution of various prognostic factors. RESULTS: The overall response rates were 76% with imipenem plus amikacin, 72% with imipenem, 71% with ceftazidime plus amikacin, and 59% with ceftazidime alone. Single-organism gram-positive infections occurred in 101 of 750 episodes. Without a change in antibiotics, the response rates were 50% with imipenem, 40% with imipenem plus amikacin, 39% with ceftazidime plus amikacin, and 38% with ceftazidime. Most responded to vancomycin or other antibiotics, and the mortality associated with gram-positive infections was only 5%. Regardless of the antibiotic regimen, the majority of uncomplicated gram-negative infections responded to therapy and the majority of complicated gram-negative infections failed to respond. Multivariate logistic-regression analysis showed that recovery of the neutrophil count was the most favorable prognostic factor in a patient's response to infection, whereas the presence of gram-positive infection, acute leukemia, pulmonary or enteric infection, and therapy with ceftazidime were unfavorable factors. CONCLUSIONS: Single-agent therapy with imipenem is as effective as more conventional combination antibiotic therapy for the empirical treatment of febrile episodes in neutropenic patients with cancer.

Adolescent

Significance of the P210 versus P190 molecular abnormalities in adults with Philadelphia chromosome-positive acute leukemia.

We investigated the significance of p210 and p190 molecular abnormalities in 32 adults with Philadelphia chromosome (Ph)-positive acute leukemia. p210 was detected in 15 patients (47%), p190 in 16 (50%), and both in one (3%). p210 was noted in 11 of 24 patients (46%) with acute lymphocytic leukemia, and in four of eight patients (50%) with acute myelogenous or undifferentiated leukemia. Among 29 patients with untreated disease (p210, 14 patients; p190, 15 patients), no significant differences in the two molecularly distinct groups were observed by pretreatment characteristics including age, degree of organomegaly, anemia, leukocytosis, thrombocytopenia, occurrence of karyotypic abnormalities in addition to Ph, or residual diploid metaphases. Complete response (CR) rates were also similar. Although the remission duration tended to be longer with p190 (P = .08), the differences were minor (median duration 29 v 20 weeks) and not paralleled by differences in survival rate. In 10 patients studied by karyotypic analysis in remission, two of four patients with p190 and two of six patients with p210 showed 100% normal metaphases. One of the seven patients (14%) with p210 who achieved CR manifested a morphologic picture of second chronic-phase chronic myelogenous leukemia lasting for 1 month. We conclude that the molecular studies in Ph-positive acute leukemia are not associated with significantly different clinico-laboratory, karyotypic, or prognostic implications.

Adult

Intensive chemotherapy induction followed by interferon-alpha maintenance in patients with Philadelphia chromosome-positive chronic myelogenous leukemia.

In a pilot study, 32 patients with Philadelphia chromosome-positive chronic myelogenous leukemia were treated with intensive chemotherapy induction followed by interferon-alpha (IFN-A) maintenance. Intensive chemotherapy consisted of three cycles of daunorubicin 120 mg/m2 on day 1, cytarabine 80 mg/m2 daily for 10 days, vincristine 2 mg on day 1, and prednisone 100 mg daily for 5 days (DOAP). Maintenance therapy with IFN-A at a doses of 3 x 10(6) to 5 x 10(6) units/m2 daily was adjusted according to counts and toxicity. The outcome of patients was compared with a matched historic population of 64 patients treated with IFN-A alone. Overall, 60% of patients had a cytogenetic response (partial or complete) with induction chemotherapy, but only eight (25%) had a sustained cytogenetic response with IFN-A maintenance. After a median follow-up of 67 months, the 6-year survival rate of the 32 patients was 58%, compared with 36% for the matched historic group (P = 0.084). The incidence of lymphoid blastic transformation in the two groups was 25% and 48%, respectively (P = 0.10) and durable cytogenetic responses, 25% and 19%, respectively (P = 0.48). In summary, the addition of intensive chemotherapy induction to IFN-A maintenance does not improve the survival rate, incidence of lymphoid blastic transformation, or incidence of durable cytogenetic response compared with the results achieved with IFN-A therapy alone.

Adolescent