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Biomedical subjects

M R Grever

Publications and source records attributed to M R Grever.

At least 73 records · Page 4Linked to original sources

Report of the National Cancer Institute-sponsored workshop on definitions of diagnosis and response in acute myeloid leukemia.

The National Cancer Institute (NCI) sponsored a workshop to develop a set of standardized diagnostic and response criteria for acute myeloid leukemia (AML) clinical trials. The French-American-British (FAB) classification was retained for diagnosing AML, with the addition of patients with bone marrow morphologic features of a myelodysplastic syndrome and less than 30% bone marrow blasts, but with greater than or equal to 30% blasts in the peripheral blood. In this report, there are four important subgroups of AML not defined in the FAB classification that are discussed: undifferentiated acute leukemia, MO (AML lacking definitive myeloid differentiation by morphology or conventional cytochemistry but with ultrastructural or immunophenotypic evidence for AML), mixed lineage leukemia, and hypocellular AML. Definitions of response for clinical trials are presented to facilitate comparisons among different studies. Complete remission is considered the only response worth reporting in phase III trials, since lesser responses do not improve survival. Partial remissions may be of interest to identify active new agents in phase I and II studies. Monoclonal antibodies and cytogenetic studies are not part of the routine assessment of remission or reassessment at relapse, and their role in the evaluation of patients with AML is currently being evaluated in clinical trials. Although we recognize that some of the definitions in this report are arbitrary, generalized use of these guidelines will make results of clinical trials more comparable and interpretable.

Antibodies, Monoclonal↗

Immunosuppressive effects of pentostatin.

The immune function of patients with hairy cell leukemia (HCL) and solid tumors was evaluated before and after treatment with the investigational drug 2'-deoxycoformycin (pentostatin; dCF). Thirteen HCL patients received doses of dCF of 2 to 4 mg/m2 intravenously at 2- to 6-week intervals for up to 15 courses. After completion of treatment, 12 of 13 patients had resolution of severe monocytopenia and five of nine had normal monocyte antibody dependent cellular cytotoxicity. There was statistically significant depression of total lymphocytes, T cells, and B cells. Evaluation of T subsets showed a decrease in CD4+ cells. Immunoglobulin G (IgG) in sera were decreased from baseline, while IgM and IgA were unaffected. There was no significant effect on skin-test reactivity or large granular lymphocyte numbers. Lymphoblastic transformation was variably affected. Natural-killer (NK) cell function was improved or unchanged after dCF treatment. Reevaluation of seven patients at 21 to 119 weeks after receiving dCF demonstrated that recovery to normal T- and B-cell numbers and subsets does occur. Five solid tumor patients were given dCF at 4 mg/m2 intravenously at 1- to 2-week intervals for up to five courses. There was significant reduction in T cells, B cells, CD4+, and CD8+ cells with no statistically significant effect on the other immune parameters. We conclude that low doses of dCF can cause persistent immunosuppression though recovery may occur after the drug is stopped. In patients followed after completion of dCF, there was no associated increase in second malignancies or unusual infections.

Antibody-Dependent Cell Cytotoxicity↗

Pharmacokinetics of 2-F-ara-A (9-beta-D-arabinofuranosyl-2-fluoroadenine) in cancer patients during the phase I clinical investigation of fludarabine phosphate.

Fludara I.V. (fludarabine phosphate) (2-F-ara-adenosine monophosphate [2-F-ara-AMP], NSC 312887) is the 5'-phosphate of 2-F-ara-A-(9-beta-D-arabinofuranosyl-2-fluoroadenine), a derivative of ara-A that is resistant to deamination and selectively inhibits DNA synthesis. Concurrent with the phase I evaluation of 2-F-ara-AMP administered as a single intravenous (IV) bolus every 21 days to patients with advanced malignancy, plasma pharmacokinetic profiles of 2-F-ara-A were determined in 30 patients following the rapid infusion (2 to 5 minutes) of doses of 2-F-ara-AMP ranging from 80 to 260 mg/m2. The parent drug was almost quantitatively converted to 2-F-ara-A by apparent first-pass metabolism, with maximum levels of 2-F-ara-A and very low levels (less than 1 fmol/L) of 2-F-ara-AMP observed only in the plasma samples obtained shortly after dosing (2 to 4 minutes). The plasma concentration-time profiles exhibited three exponential phases. Plasma concentrations were computer fitted to a three-compartment open model using a zero-order input function for the injection period. The 2-F-ara-A harmonic mean half-lives were t1/2 alpha = 4.97 minutes, t1/2 beta = 1.38 hours, t1/2 gamma = 10.41 hours, and the mean residence time was 10.51 hours. The rate-limiting process for elimination of the drug from the body appeared to be release from tissue binding sites. The mean total-body plasma clearance was 67.98 +/- 19.58 mL/min/m2 (mean +/- SD). The mean central compartment volume of distribution (V1) was 7.49 L/m2 or 0.20 L/kg. The mean steady-state volume of distribution (Vdss) was 44.17 L/m2 or 1.19 L/kg, indicating that 2-F-ara-A is distributed and bound to the tissues of the body. Total-body clearance and the volume parameters Vdss and Vd gamma decreased with an increase in serum creatinine, indicating that these pharmacokinetic parameters depend upon renal function. Dose reduction in patients with renal dysfunction is recommended.

Antimetabolites, Antineoplastic↗

Pathogenetic implications of internuclear bridging in myelodysplastic syndrome. An Eastern Cooperative Oncology Group/Southwest Oncology Group Cooperative Study.

Numerous morphologic features have been described in bone marrow and peripheral blood in myelodysplastic syndrome (MDS). We draw attention to a high incidence of a subtle morphologic feature, internuclear bridging (INB), not previously recognized as a morphologic feature in MDS. The occurrence of INB in MDS suggests an underlying abnormality of mitotic division that could explain the impaired production of hematopoietic cells, the addition and deletion cytogenetic changes, and the stepwise disease progression and cytogenetic progression characteristic of MDS. Lack of awareness that INB occurs in MDS may cause confusion of MDS and congenital dyserythropoietic anemia type I, a congenital process also characterized by INB.

Bone Marrow↗

Marrow transplantation following busulfan and cyclophosphamide for chronic myelogenous leukaemia in accelerated or blastic phase.

Between July 1984 and October 1987, 21 patients with chronic myelogenous leukaemia in an accelerated or blastic phase were treated with 16 mg/kg of busulfan and 120 mg/kg of cyclophosphamide followed by infusion of bone marrow from an HLA-identical sibling donor. The regimen was well tolerated. Except for one individual with severe marrow fibrosis all patients achieved a complete remission. Only one patient relapsed. Seven of 13 patients transplanted in an accelerated phase and five of eight transplanted in a blastic phase are alive without Philadelphia chromosomes between 8 and 48 months (median 29 months) following transplantation. The estimated probability of relapse-free 3-year survival is 55%. These results indicate that busulfan and cyclophosphamide combined with allogeneic marrow transplantation exert a potent anti-leukaemic effect in patients in the accelerated or blastic phase of CML.

Adolescent↗

Pentostatin in the treatment of advanced hairy cell leukemia.

2'-Deoxycoformycin (pentostatin [dCF]), a potent inhibitor of adenosine deaminase (ADA), was administered in a biweekly low-dose (2 to 4 mg/m2) intravenous (IV) schedule to patients with advanced hairy cell leukemia. Twenty-three patients were treated, including 12 patients previously treated by splenectomy and five patients treated with interferon. Twenty-one of 23 patients had objective responses, including 20 who achieved a complete remission (CR). Responses occurred rapidly, with an average time to CR of 5.4 months. Treatment was not continued once CR was achieved, and 15 of 20 patients remain in remission with an average duration of 12.6 months. CRs were achieved in both patients previously treated with interferon (three of five) and patients with marked splenomegaly (three of three). Relapses, when seen, have occurred in the bone marrow alone and the one patient who required retreatment was reinduced into CR. Toxicity has been mild and reversible, with nausea and vomiting, conjunctivitis, and skin rash as the main complications of treatment. dCF is the most effective single agent in the treatment of hairy cell leukemia, inducing a high percentage of CRs in all subgroups. Two multiinstitutional trials are now underway to compare its effectiveness v alpha interferon.

Adult↗

Phase I clinical investigation of fludarabine phosphate by a loading-dose and continuous-infusion schedule.

Fludarabine phosphate was studied in a phase I trial of a loading-dose/continuous-infusion schedule. The schedule was chosen to rapidly achieve and maintain concentrations that have been shown in vitro to achieve maximal inhibition of cell growth. The initial level was a loading dose of 20 mg/m2 followed by a 48-hour continuous iv (CIV) infusion of 30 mg/m2 every 24 hours. For the single-dose escalation, the loading dose was held constant while the CIV dose was increased to 45 mg/m2/24 hours for 48 hours. The dose-limiting toxicity was myelosuppression, especially leukopenia. No other significant toxicity was encountered. The maximum tolerated dose was 20 mg/m2 by iv push followed by a 48-hour CIV infusion of 30 mg/m2/24 hours for 48 hours. The recommended starting dose for phase II trials is 20 mg/m2 by iv push followed by a 48-hour CIV infusion of 30 mg/m2/24 hours. This dose level achieved the target plasma levels in the 2 patients studied.

Adult↗

Guidelines for clinical protocols for chronic lymphocytic leukemia: recommendations of the National Cancer Institute-sponsored working group.

The National Cancer Institute (NCI)-sponsored Chronic Lymphocytic Leukemia (CLL) Working Group was convened to develop a set of standardized eligibility, response, and toxicity criteria for clinical trials. We recognized the previous efforts in 1967 (published again in 1973 as the report of the Chronic Leukemia-Myeloma Task Force [1] and 1978 of Cancer and Leukemia Group B (CALGB) [2]). We have used these reports for guidance during the current effort. Several noteworthy developments in the past few years have made it necessary to modify the previous guidelines. First, the diagnostic criteria for CLL and its clinical staging have been developed and well defined. Second, although staging systems facilitated entry of comparable and relatively homogeneous groups of patients in clinical trials, the definitions of response (CR) and partial response (PR) were not uniformly adopted from the previous guidelines in the clinical trials (Tables IA, IB); therefore, comparisons of results obtained in different studies became difficult. Third, there has been an improvement in our understanding of the immunology and biology of CLL. Finally, we are witnessing the emergence of several chemotherapy agents that promise impressive activity in CLL (e.g., 2'-deoxycoformycin [3], fludarabine monophosphate [4, 5]), and thereby offer the potential for improving survival time in this disease. To best identify regimens worthy of continued pursuit in large comparative trials, standardized guidelines for evaluation are essential. A number of laboratory investigations are also presented for which scientific interest is high yet relevance remains to be determined; thus, they are presented as companion studies to the clinical trials. This mechanism allows for flexibility in the testing of these questions and for additional ideas in the future without requiring modification of an entire treatment protocol. The following guidelines were developed to be used as a form of standardization for clinical trials, incorporating current technologies, yet remaining relevant to the general hematology/oncology community. Based on the membership of the Working Group, it is expected that these guidelines will serve as the criteria for most clinical trials in the near future.

Antineoplastic Agents↗

Fludarabine monophosphate: a potentially useful agent in chronic lymphocytic leukemia.

Recent developments in experimental chemotherapy may benefit patients with chronic lymphocytic leukemia (CLL). Fludarabine monophosphate has shown promise in heavily pretreated patients with advanced CLL. The Southwest Oncology Group has recently completed a phase II investigation of fludarabine in 32 patients. The patient population had a median age of 63 years, median performance status of 1, and included patients with the following stages of the disease: stage 0-3 patients; stage I-5 patients; stage II-6 patients; stage III-4 patients; stage IV-14 patients. A total of 176 courses were administered. Myelosuppression was the most frequent toxicity observed with 13 patients having a decline in platelets, and 11 patients having some decline in granulocytes. Fludarabine monophosphate has had unequivocal antileukemic activity in a group of patients with advanced CLL.

Adult↗

Pharmacologic marrow purging in murine T cell leukemia.

Deoxycoformycin in combination with deoxyadenosine was used to purge 6C3HED malignant T cells from murine marrow in vitro. Adenosine deaminase activity of 6C3HED cells was ablated by incubation with 10(-6) mol/L deoxycoformycin (dCF). During a 12-hour incubation with 10(-6) mol/L dCF and 10(-4) mol/L deoxyadenosine, tumor cells sequentially accumulated dATP, became depleted of NAD followed by ATP, then died. More than 5 logs of 6C3HED cells were killed as measured by survival of mice injected with treated tumor cells. Identical incubation of 5 x 10(6) marrow cells did not interfere with rescue of syngeneic lethally irradiated mice. Long-term survival was demonstrated in 12 of 14 mice that received marrow that had been contaminated with 5% 6C3HED cells, incubated with deoxycoformycin and deoxyadenosine, then used to rescue lethally irradiated mice. This murine model provides information not available from in vitro assays and may be useful in the development of strategies to purge malignant T cells from marrow.

5'-Nucleotidase↗

Phase II trial of 9-beta-D-arabinofuranosyl-2-fluoroadenine 5'-monophosphate in non-Hodgkin's lymphoma: prospective comparison of response with deoxycytidine kinase activity.

A phase II study of 9-beta-D-arabinofuranosyl-2-fluoroadenine 5'-monophosphate was done in non-Hodgkin's lymphoma with a loading dose/continuous intravenous infusion schedule, consisting of a 20 mg/m2 loading dose followed by a continuous i.v. infusion of 30 mg/m2/24 h for 48 h. The loading dose was held constant while the continuous i.v. dose was escalated or decreased as appropriate for toxicity. Twenty-six patients were entered on the study; 25 are evaluable for response. The patients' median age was 61 years (range 25 to 73); their mean performance status was 1.1. They had received a mean of 2.6 prior chemotherapeutic regimens, and six also had prior radiation therapy. There was one complete response lasting 9+ months, and there were seven partial responses lasting 20, 13, 11, 11, 10, 5, and 2 months (response rate 32%). Toxicity was acceptable and consisted mainly of myelosuppression. 9-beta-D-arabinofuranosyl-2-fluoroadenine 5'-monophosphate is dephosphorylated in vivo and then is thought to be activated intracellularly to 9-beta-D-arabinofuranosyl-2-fluoroadenine 5'-triphosphate. The rate-limiting enzyme is deoxycytidine kinase. Deoxycytidine kinase activity was determined on pretreatment tumor samples for correlation with response. There was no difference between the values for responders and nonresponders. There was a trend for higher values in more malignant histological subtypes.

Adult↗

Treatment of hairy cell leukemia: the Ohio State University experience with deoxycoformycin.

Twelve evaluable patients with progressive hairy cell leukemia were treated with deoxycoformycin at a dose of 4 mg/m2 every 2 weeks. Five patients had not been splenectomized, and one had failed to respond to interferon-alpha. Complete remission, as defined by absence of hairy cells in the bone marrow and normalization of the peripheral blood and regression of splenomegaly, was obtained in 11 of 12 patients (92%). These patients have remained in unmaintained remission for 1+ to 13 months with an average of 7.5 months. Two of these patients had a bone marrow relapse at 8 and 12 months, respectively. During treatment the monocytopenia corrected, and, after complete remission was obtained, marrow was aspirable. Toxicity was mild and reversible. There were no significant infections associated with this treatment. It was of interest that we could treat two patients with creatinine clearance of 50 and 60 ml/min using lower doses (and 2-3 mg/m2) than our conventional therapy of 4 mg/m2 every 2 weeks. They obtained a complete remission after 6 and 10 treatments, respectively. Low-dose deoxycoformycin has proven to be an excellent treatment for hairy cell leukemia.

Adult↗

Urinary nucleosides in leukemia: laboratory and clinical applications.

Urinary nucleosides offer a number of useful laboratory and clinical applications in the study and analysis of leukemia. There are significant differences in the excretion of modified nucleosides between normal individuals and individuals with various forms of leukemia, as well as between leukemia patients at opposite ends of the clinical spectrum, i.e., those with active disease and those in remission. The nucleoside excretion levels correlate to bone marrow tumor burden in certain forms of leukemia, and limited serial data indicate the potential value of the nucleosides for predicting relapse before the disease deterioration can be recognized clinically. In addition, it may be feasible to assess the effectiveness of chemotherapy used in the treatment of leukemia much more rapidly with the urinary nucleoside markers than with conventional invasive methods.

Acute Disease↗

Combined alkylators and multiple-site irradiation for extensive small cell lung cancer: a Southwest Oncology Group Study.

The Southwest Oncology Group performed a study for patients with extensive small cell lung cancer in which two hypotheses were tested: that combined alkylating agents for induction might improve the initial response rate; and that multiple-site, involved-field consolidation with irradiation in patients with response to chemotherapy might further improve response quality and duration. A regimen of combined alkylating agents plus vincristine [carmustine, thiotepa, vincristine, and cyclophosphamide (BTOC)] was compared to our standard program of cyclophosphamide, doxorubicin, and vincristine (CAV). Patients with bone marrow metastases and/or disseminated bone metastases were randomized to BTOC or CAV as initial induction therapy, but received no multiple-field irradiation afterward. Among 189 such patients, the overall response rates were similar (48% to BTOC and 61% to CAV, with complete remission in 5% and 15%, respectively). Toxic effects were also comparative, with 23% sustaining life-threatening or fatal complications on BTOC and 16% on CAV. Median survival (5.9 and 7 months for BTOC and CAV, respectively) and overall survival were not different, and are superimposable upon our previously reported results with CAV alone. For patients with no evidence of bone marrow involvement and no metastases identified beyond the confines of ipsilateral hemithorax, liver, and brain, the plan of therapy consisted of induction chemotherapy (BTOC or CAV) every 3 weeks for three cycles, followed by multiple-field irradiation consolidation to sites of prior involvement. Among 239 such patients, response rates to therapy initiated with BTOC and CAV were also similar: 54% for BTOC and 62% for CAV, with complete response in 16% and 13%, respectively. However, the program of BTOC followed by multiple-site irradiation was associated with a higher incidence of severe or life-threatening thrombocytopenia (23% versus 8% for CAV), accounted for almost entirely by patients receiving hepatic irradiation after chemotherapy, among whom the incidence of this complication (grade 3 or 4) was 76% and 14%, respectively. Other toxic effects, including granulocytopenia, were comparable. With the exception of thrombocytopenia in the cited subgroup, multiple-field irradiation consolidation proved feasible and tolerable, with improved quality of response evident after its initiation in 24% of 135 patients. However, a similar proportion developed disease progression during or shortly after radiation therapy, and the median survival of patients who received irradiation was only 9 months (7 months from the start of consolidation).(ABSTRACT TRUNCATED AT 400 WORDS)

Antineoplastic Combined Chemotherapy Protocols↗

Low-dose deoxycoformycin in the treatment of hairy cell leukemia.

Ten patients with progressive hairy cell leukemia were treated with 2'deoxycoformycin (dCF) by intravenous bolus (4 mg/m2) given every other week. All ten patients are evaluable for response and nine of the ten patients have achieved a complete remission. In addition to clearing of hairy cells from the bone marrow, eight patients had resolution of their monocytopenia. Seven of the nine patients remain in unmaintained remission with a median duration of 6.2 months. Two patients have had relapse in the bone marrow alone and continue to have normal peripheral blood counts. They are being followed without treatment. Toxicity was minimal at this low dose with one patient having a mild reversible reduction in creatinine clearance. Four other patients had reversible neutropenia. There were no significant infections associated with treatment. Low-dose deoxycoformycin administered intravenously every other week represents an extremely effective treatment for hairy cell leukemia.

Adenosine Deaminase↗