Search PubMed⌕ Search

Biomedical subjects

C B Miller

Publications and source records attributed to C B Miller.

At least 37 records · Page 2Linked to original sources
PubMed1997

Utility of fiberoptic bronchoscopy in bone marrow transplant patients.

Fiberoptic bronchoscopy (FOB) has been reported to have a high diagnostic yield and to be safe in BMT patients with pulmonary infiltrates. At our institution, BMT patients with respiratory symptoms and/or pulmonary infiltrates had a thoracic CT and bronchoalveolar lavage (BAL). Transbronchial biopsy (TBBx) was considered if the platelet count could be raised to >30 x 10(9)/l. From March 1993 to August 1995, 52 patients had 68 FOBs (42 BAL + TBBx, 26 BAL only) for 60 episodes of clinical pneumonia. Patients' characteristics were: 38 males, mean age 42 years, and 39 allogeneic BMTs. Of the 68 FOBs, 47 were performed to evaluate diffuse infiltrates, 10 were done on mechanically ventilated patients, and 50 of the FOBs were preceded by a platelet transfusion. Thirty-one percent of FOBs (21 FOBs, 19 patients) were diagnostic. Twenty-four percent of FOBs (11 diagnostic FOBs, six nondiagnostic FOBs) changed therapy. Ten complications (15%) occurred in 10 FOBs (five acute respiratory failure, three pneumothoraces, one nose bleed, one death). Hospital and 6-month survival based on episodes of clinical pneumonia were 47 and 32%, respectively. Patients who had a diagnostic FOB or a FOB that changed treatment did not have better hospital or 6-month survival compared to patients who had FOBs that were nondiagnostic or did not change treatment. FOB in our BMT patient population, had a low diagnostic yield (31%), infrequently changed treatment (24%), a significant complication rate (15%) and was not associated with improved patient survival. The role of routine diagnostic FOB in BMT patients with pulmonary infiltrates and/or respiratory symptoms should be reevaluated.

Adolescent↗
PubMed1996

Impact of age on outcome of patients with cancer undergoing autologous bone marrow transplant.

PURPOSE: We examined the impact of age on outcomes in patients with cancer undergoing autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: All 506 adult patients who underwent ABMT at the Johns Hopkins Oncology Center between January 1987 and January 1994 were studied. A total of 405 patients were aged 18 to 49 years and 101 were aged > or = 50. The effect of age and other prognostic variables on transplant-related mortality (TRM), relapse, and event-free survival rates were analyzed. RESULTS: Patients aged > or = 50 years has a 2.24-fold increased risk of TRM. Although relapse rates were not different based on age, the increased TRM rate resulted in a slight decrease in overall event-free survival in the older patients. Causes of death were not different by age and were mainly related to preparative regimen toxicity. Length of hospital stay and hospitalization costs were not increased in the older patients. CONCLUSION: While the TRM rate was higher in older patients, relapse rates were not increased. Nearly 25% of older patients were expected to be cured of the disease. These data support the use of ABMT in eligible older patients, at least up to the age of 65.

Adult↗
PubMed1996

A phase I and pharmacological study of topotecan infused over 30 minutes for five days in patients with refractory acute leukemia.

The principal objectives of this study were to determine the feasibility of escalating doses of the hydrophilic topoisomerase I (topo I) inhibitor topotecan (TPT) as a 30-min infusion daily for 5 days in adults with refractory or relapsed acute leukemia and to study the pharmacokinetic behavior of high doses of TPT and pharmacodynamic determinants of TPT activity. Fourteen patients received 27 courses of TPT at doses ranging from 3.5 to 5.75 mg/m2/day every 3 weeks. A constellation of unusual adverse effects, consisting of high fever, rigors, precipitous anemia, and hyperbilirubinemia, was the principal dose-limiting toxicity of high doses of TPT on this schedule. These toxicities were consistently intolerable at the 5.75 mg/m2/day dose level; however, they were neither severe nor common at lower doses. Although the precise etiology of these effects is not known, high doses of TPT may induce acute hemolytic reactions in this patient population. Severe, albeit transient, mucositis was experienced by two of eight patients in 2 of 17 courses at the next lower dose level, 4.5 mg/m2/day, which was determined to be the maximum tolerated dose and the dose recommended for further trials. The pharmacokinetic behavior of TPT at high doses was not dose dependent and resembled that at lower doses. In view of preclinical data suggesting that TPT sensitivity might correlate with topo I levels, topo I content in leukemia blasts was assessed by Western blotting. Variations in topo I content were observed. Moreover, strong correlations were evident between topo I content and two markers of proliferation, proliferating cell nuclear antigen and nuclear protein B23, raising the possibility that differences in topo I content observed among various leukemia specimens might reflect differences in the proliferating fractions of cells in various leukemia samples. Although complete clearance of circulating leukemia blasts occurred in most courses, neither sustained responses nor hematopoietic recovery were observed in the heavily pretreated, poor-risk patients enrolled in this study, and it was not possible to correlate these differences in topo I content with clinical response. These results indicate that substantial dose escalation of TPT as a 30-minute infusion for a 5-day schedule above myelosuppressive doses is feasible in adults with refractory or relapsed leukemias; however, further development of alternate high-dose schedules in leukemia may be warranted in view of the nature of the dose-limiting toxicity and the lack of sustained clinical responses in this preliminary investigation.

Acute Disease↗
PubMed1995

Association of BK virus with failure of prophylaxis against hemorrhagic cystitis following bone marrow transplantation.

PURPOSE: Hemorrhagic cystitis (HC) after bone marrow transplantation (BMT) has been ascribed to cyclophosphamide metabolites. HC has also been associated with excretion of the BK type of polyomavirus. The relative contributions of cyclophosphamide metabolites and BK virus in the development of HC following BMT are unknown. PATIENTS AND METHODS: We conducted a randomized trial to compare mesna with forced diuresis for prophylaxis against HC in 147 BMT recipients. We studied the association of BK virus with HC in 95 consecutive BMT recipients by prospectively monitoring urinary excretion of BK virus using polymerase chain reaction amplification of viral gene sequences. RESULTS: HC occurred in 37 of 147 (25.2%) transplant recipients. The incidence of HC was similar in patients given mesna (26.8%, 19 of 71) or forced diuresis (23.7%, 18 of 76), and in recipients of allogeneic (27.2%, 18 of 64) or autologous marrow (22.9%, 19 of 83). The incidence of HC was unrelated to primary disease, preparative regimen, or occurrence of graft-versus-host disease (GVHD). Excretion of BK virus was demonstrated in 50 of 95 patients (52.6%); 38 patients (40%) had persistent BK viruria (> or = two consecutive positive samples). HC occurred in 19 of 38 patients (50%) with persistent BK viruria, in one of 12 (8.3%) with only a single urine sample positive for BK virus, and in none of 45 who did not excrete BK virus (P < .0001). Shedding of BK virus also had a strong temporal correlation with onset of HC (r = .95). CONCLUSION: Mesna and forced diuresis are equally effective in abrogating the urothelial toxicity of preparative regimens for BMT. Since HC after BMT is virtually always associated with persistent BK viruria, strategies aimed at the prevention or elimination of viruria in BK seropositive recipients are warranted.

Adult↗
PubMed1994

Topoisomerase II levels and drug sensitivity in adult acute myelogenous leukemia.

The topoisomerase (topo) II-directed agents etoposide, daunorubicin (DNR), and amsacrine (m-AMSA) are widely used in the treatment of acute myelogenous leukemia (AML). In the present study, multiple aspects of topo II-mediated drug action were examined in marrows from adult AML patients. Colony-forming assays revealed that the dose of etoposide, DNR, or m-AMSA required to diminish leukemic colony formation by 90% (LD90) varied over a greater than 20-fold range between different pretreatment marrows. Measurement of nuclear DNR accumulation in the absence and presence of quinidine revealed evidence of P-glycoprotein (Pgp) function in 8 of 82 samples at diagnosis and 5 of 36 samples at first relapse, but the largest quinidine-induced increment in DNR accumulation (< 2-fold) was too small to explain the variations in drug sensitivity. Restriction enzyme-based assays and sequencing of partial topo II alpha and topo II beta cDNAs from the most highly resistant specimens failed to demonstrate topo II gene mutations that could account for resistance. Western blotting of marrow samples containing greater than 80% blasts revealed that the content of the two topo II isoenzymes varied over a greater than 20-fold range, but did not correlate with drug sensitivity in vitro or in vivo. In addition, levels of topo II alpha and topo II beta in 46 of 47 clinical samples were lower than in human AML cell lines. Immunoperoxidase staining showed that these low topo II levels were accompanied by marked cell-to-cell heterogeneity, with topo II alpha being abundant in some blasts and diminished or absent from others. There was a trend toward increasing percentages of topo II alpha-positive cells in pretreatment marrows that contained more S-phase cells. Consistent with this observation, treatment of patients with granulocyte-macrophage colony-stimulating factor for 3 days before chemotherapy resulted in increases in topo II alpha-positive cells concomitant with increases in the number of cells traversing the cell cycle. These observations have implications for the regulation of topo II in AML, for the use of topo II-directed chemotherapy, and for future attempts to relate drug sensitivity to topo II levels in clinical material.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Erythropoietin after bone marrow transplantation.

The anemia associated with bone marrow transplantation is in part related to a relative erythropoietin deficiency. Recombinant human erythropoietin has been studied in different clinical situations. After allogenic bone marrow transplant, recombinant human erythropoietin has enhanced erythroid engraftment and in several studies, decreased transfusion requirement.

Anemia↗
PubMed1993

Transient normalization of lymphocyte blastogenic and specific antibody responses following boosting of healthy elderly subjects with tetanus toxoid.

The diminished in vitro blastogenic response of lymphocytes from the elderly to mitogenic stimuli is cited as evidence of immunosenescence, but the response to specific microbial antigens has not been well characterized. We measured the response to tetanus toxoid before and after boosting in young and elderly subjects. Elderly subjects (age > or = 70) and young controls (age < 35) were subjected to clinical, laboratory, and nutritional evaluation to ensure a cohort of healthy subjects. Responses of lymphocytes from the elderly to the mitogens phytohemagglutinin and concanavalin A were markedly diminished compared to those from the young. For all subjects, the average in vitro blastogenic response to tetanus toxoid of lymphocytes from elderly subjects (n = 23) was significantly diminished compared to young controls (n = 23; 31,985 +/- 4502 vs 14,411 +/- 3714 cpm, p < .01). Following boosting with tetanus in those subjects in whom boosting with tetanus toxoid was indicated, blastogenesis was comparable between elderly (n = 17) and young subjects (n = 7; 38,078 +/- 11,451 vs 42,103 +/- 9247 cpm). The boosted response to tetanus apparently was not sustained, since in the subset of subjects with a history of tetanus immunization in the past 10 years, the response of the elderly was much less than that of the young. Thus, a cohort of healthy elderly with diminished blastogenic responses to mitogens was capable of at least a transiently normal response to tetanus post boosting.

Adult↗
PubMed1993

Association of Torulopsis glabrata infections with fluconazole prophylaxis in neutropenic bone marrow transplant patients.

Because the use of fluconazole prophylaxis had been associated with an increased rate of Candida krusei infections at The John Hopkins Oncology Center, early empiric amphotericin B plus flucytosine were given to febrile neutropenic patients colonized by C. krusei. By this practice, the proportion of fungemias attributable to C. krusei was low (12.5%) in patients receiving fluconazole over a 6-month interval. However, Torulopsis (Candida) glabrata assumed a much higher proportion of fungemias (75%) among patients receiving fluconazole. In vitro susceptibility testing combined with this clinical experience suggests that some T. glabrata isolates are not susceptible to fluconazole and can cause breakthrough infections in patients receiving fluconazole.

Amphotericin B↗
PubMed1993

BMT for severe aplastic anemia using cyclosporine.

Between 1984 and 1991 24 patients with severe aplastic anemia (SAA) were transplanted with HLA identical sibling donor BM. The overall long-term survival was 79 +/- 8%. The average age was 21 years (range 4-53 years) and the median pre-transplant disease duration was 35 days (range 12-2998 days). Over one-half (15 of 24) of the patients had received > 10 units of blood product transfusions prior to BMT. The pre-transplant conditioning regimen consisted of 200 mg/kg cyclophosphamide (CY). Cyclosporine (CYA) was administered from 2 days prior to BMT and continued for 6-12 months. Two of the 24 patients failed to achieve primary engraftment (FTE). One of these patients had autologous recovery of BM function and is alive and well. Five of the 22 patients who engrafted failed to sustain engraftment (FTSE). Of these, three are alive and well following a second BMT or marrow boost. Only 1 of the 22 patients who engrafted had clinically significant (i.e. Stage II-IV) acute GVHD. No patient developed chronic GVHD. Our results indicate that BMT following a regimen consisting of CY with the continuous use of CYA in the post-transplant period is well tolerated and associated with excellent long-term survival. The high incidence of secondary graft instability (i.e. FTSE), however, suggests that future studies should focus on post-transplantation immunomodulation.

Adolescent↗
PubMed1992

Impaired erythropoietin response to anemia after bone marrow transplantation.

Delayed erythroid recovery is common after bone marrow transplantation (BMT), with some patients continuing to require red blood cell (RBC) transfusion support for as long as 1 year. While the etiology is multifactorial, inadequate stimulation of erythroid progenitors by the erythroid growth factor, erythropoietin, may play a role. In this study, the erythropoietin response to anemia of 70 consecutive patients undergoing BMT at the Johns Hopkins Oncology Center was compared with the erythropoietin response in uncomplicated iron deficiency anemia. Erythropoietin levels were elevated for the degree of anemia early after BMT; however, at the time of marrow recovery, erythropoietin levels were significantly suppressed in both allogeneic and autologous BMT patients compared with the iron-deficient patients. Patients with acute graft-versus-host disease (GVHD) had a more marked suppression of the erythropoietin response to anemia. In the patients who remained anemic for extended periods of time (up to 12 months after BMT), an inadequate erythropoietin response to anemia persisted. Delayed erythroid recovery after BMT is associated with inadequate erythropoietin levels. Therefore, recombinant human erythropoietin may be useful in the treatment of the anemia associated with both autologous and allogeneic BMT.

Anemia↗
PubMed1992

Phase I-II trial of erythropoietin in the treatment of cisplatin-associated anemia.

BACKGROUND: Cancer patients undergoing chemotherapy with cisplatin-containing regimens often develop anemia. Although the cause is multifactorial, erythropoietin deficiency appears to play an important role. Recombinant human erythropoietin (epoetin) has been reported to be effective in reversing cisplatin-associated anemia in animal studies but not in clinical trials. PURPOSE: This pahse I-II clinical trial was designed to assess the safety and efficacy of treatment with epoetin for anemia associated with cisplatin chemotherapy. METHODS: Twenty-one cancer patients treated with cisplatin and manifesting anemia (hemoglobin level less than 110 g/L) received epoetin at escalating doses (25, 50, 100, or 200 U/kg body weight) intravenously five times a week for 4 weeks. RESULTS: Epoetin was well tolerated, and a maximal tolerated dose was not reached. Two patients experienced hypertension, which responded to standard antihypertensive therapy. No dose-dependent severe toxic effects were seen. The increase in hemoglobin levels from baseline on day 1 of the study was statistically significant after 4 weeks of epoetin therapy in the groups receiving 100 U/kg (mean change +/- SD = 19 +/- 13 g/L; P = .03) or 200 U/kg (mean change = 24 +/- 17 g/L; P = .007). A clinical response--an increase in hemoglobin level greater than 10 g/L--was achieved in 12 patients after 4 weeks of treatment. For these responders, the mean increase in hemoglobin level was 25 +/- 3.3 g/L over the level observed at the same time in the chemotherapy cycle preceding epoetin treatment, and this increase was statistically significant (P = .0001). Neither serum erythropoietin level nor hemoglobin level predicted a patient's response to epoetin. CONCLUSIONS: These preliminary findings suggest that epoetin is effective and well tolerated for the reversal of cisplatin-associated anemia, with the 100-U/kg and 200-U/kg dose levels offering optimal clinical response. IMPLICATIONS: We are conducting a phase III trial to determine the effect of epoetin on transfusion requirements in patients undergoing chemotherapy.

Adult↗
PubMed1991

Correlation of occult clonogenic leukemia drug sensitivity with relapse after autologous bone marrow transplantation.

Despite initial complete remission rates exceeding 70%, the majority of patients with acute myeloid leukemia (AML) and adults with acute lymphocytic leukemia (ALL) eventually relapse. Improving the therapeutic results in acute leukemia requires detecting, and understanding the biology of, the minimal residual leukemia remaining after therapy and responsible for relapse. To investigate the biologic relevance of an in vitro assay for clonogenic leukemia (leukemia colony-forming units [CFU-L]) as a measure of minimal residual leukemia, we studied 58 consecutive patients with acute leukemia in complete remission undergoing autologous bone marrow transplantation (BMT) with cyclophosphamide-based therapy. CFU-L were cultured from the pretransplant remission marrows in 45 of 58 patients: 35 of 43 patients with AML and 10 of 15 with ALL. Clonal rearrangements, identical to the patients' overt leukemia when available, were detected in the occult CFU-L from four of the eight patients with ALL in whom adequate DNA for analysis could be obtained from the CFU-L. None of the uncultured pretransplant remission marrows from the 15 ALL patients showed clonal gene rearrangements. We also determined the in vitro sensitivity of the occult CFU-L to 4-hydroperoxycyclophosphamide (4HC), and correlated these results with the outcome of the patients. The sensitivity of the occult CFU-L to 4HC was the only factor that predicted relapse following BMT. The actuarial probability of relapse was 18% in the 23 patients whose CFU-L were sensitive to 4HC compared with 77% in the 22 patients whose CFU-L were resistant (P less than .001). The only factor that influenced the CFU-L sensitivity to 4HC was the type of leukemia. The CFU-L from the AML patients were more sensitive to 4HC than the CFU-L from the ALL patients (P = .001). Occult CFU-L genetically and functionally represent occult leukemia. Therefore, the CFU-L assay should provide a means for studying the biology of minimal residual leukemia and improving the therapeutic results in patients with acute leukemia.

Adolescent↗
PubMed1991

Evolution of a near-triploid karyotype in a secondary erythroleukemia.

We report a case of erythroleukemia (EL;FAB M6), preceded by a myelodysplastic phase, in a 50-year-old male 8 years after treatment for Hodgkin's lymphoma. Cytogenetic analysis of bone marrow at time of diagnosis of EL revealed three cell lines: 1) 28 of 53 cells (53%) were hypodiploid, 43,XY,-5,-7,-12; 2) 23 of 53 cells (43%) were near-triploid, stemline 67-69,XY,+2,del(5)(q11.2),+del(5)(q11.2),+6,-7,+8,-9,-11,-12,+15,-16,der (17)t (17;?) (p11.2;?),-18,-20,-20,+22,+r, + mar (relative to a complete triploid cell); 3) 2 of 53 cells (4%) were normal 46,XY. The relative monosomies of 5, 7, and 12 in both abnormal lines suggest that the near-triploid line evolved from the hypodiploid line. A single hypodiploid cell with both del(5) and der(17) chromosomes that appeared identical to those in the near-triploid line suggests that polyploidization occurred after these structural rearrangements. While EL is not characterized by any well-defined structural abnormality, reported cases are frequently hypodiploid, with occasional cases of polyploidization, as in our patient, EL in adults without previous neoplasia or recognized mutagenic exposure has been shown to have loss or deletion of chromosomes 5 and 7, also characteristic of myelodysplastic syndromes and secondary leukemia. Our patient had a relative lack of chromosomes 5 and 7 in both abnormal clones, as well as a del(5)(q11) in the near-triploid line. This case of EL clearly demonstrates the evolution of a complex near-triploid line from a hypodiploid line, with chromosome abnormalities typical of both EL and secondary leukemia.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1991

Treatment of chemotherapy-induced anemia with recombinant human erythropoietin in cancer patients.

Thirty patients with chemotherapy-induced anemia were treated with recombinant human erythropoietin for 4 weeks. In this dose-escalation study, cohorts of five to eight patients were treated per dose level. The doses of erythropoietin were 25, 50, 100, 200, or 300 IU/kg/d given intravenously for 5 days each week. Of 30 patients, 15 (50%) had a greater than 10% increase of their hemoglobin (Hb) values and were considered responders. At the two highest dose levels, 11 of 13 patients (85%) responded. In the 15 responding patients, the mean Hb level increased by 1.7 g/dL from baseline compared with an average decrease of 1.5 g/dL in the previous cycles of chemotherapy without erythropoietin administration. Recombinant human erythropoietin is effective in ameliorating chemotherapy-induced anemia when administered in adequate doses.

Adult↗
PubMed1991

Phase I study of combination drug purging for autologous bone marrow transplantation.

In a phase I clinical trial of autologous bone marrow transplantation, we determined the feasibility of ex vivo purging with high concentrations of pharmacologics in combination. Light-density cells isolated from the grafts of 26 patients with acute leukemia or lymphoblastic lymphoma were treated with 4-hydroperoxycyclophosphamide (4-HC; 30 to 60 micrograms/mL), vincristine (Vcr; 1.5 to 3.0 micrograms/mL), and methylprednisolone sodium succinate (MP; 5 mg/mL). All patients received marrow-lethal induction therapy followed by infusion of the treated grafts. Three patients died of transplant-related complications before achieving peripheral blood recovery of greater than 0.5 x 10(9) granulocytes per liter. All other patients achieved this parameter of engraftment at a median of 35 days after marrow infusion. The median time to last platelet transfusion was 45 days. These durations of aplasia were similar to those experienced by other patients receiving density-gradient separated grafts treated with 60 micrograms/mL of 4-HC as a single agent. No patient required infusion of untreated reserve marrow because of engraftment failure. The colony-forming unit-granulocyte macrophage (CFU-GM) content of the grafts after purging predicted these parameters of engraftment. Colony-forming unit-leukemia (CFU-L) cultured from the grafts of 12 of the patients treated for acute lymphoblastic leukemia (ALL) were considerably more sensitive to the combination regimen than to 4-HC alone; the sensitivity of CFU-GM from these patients did not differ between the two regimens. The results of this trial indicate the feasibility of treating autologous bone marrow grafts with high concentrations of pharmacologics in combination. The use of combinations may increase the efficacy of ex vivo purging without increasing the toxicity to normal hematopoietic cells.

Adolescent↗