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M Barcos

Publications and source records attributed to M Barcos.

At least 55 records · Page 3Linked to original sources
PubMed1990

Direct relationship between remission duration in acute myeloid leukemia and cell cycle kinetics: a leukemia intergroup study.

Cell cycle characteristics including labeling indices (LI), duration of S-phase (Ts), and total cell cycle time (Tc) were determined in 54 standard-risk, newly diagnosed patients with acute myeloid leukemia following an infusion of bromodeoxyuridine. Remission induction therapy consisting of cytosine arabinoside and daunomycin was then administered to all patients, followed by three courses of consolidation to those who achieved complete remissions (CR). Older patients appeared to have more rapidly cycling cells (P = .003). No unique cell cycle characteristics were identified for patients who achieved remission versus those who had resistant disease. However, the pretherapy cell cycle characteristics were a strong prognosticator for remission duration. CR patients were divided into those whose leukemic cell Tc were above median (A) and below median (B). Among 14 B patients, median duration of response was 211 days, and all relapsed by day 600. Among 18 A patients, the median has not as yet been reached, with nine patients in continuous complete remission (log rank P = .007, Wilcoxon P = .04). We conclude that cell cycle characteristics of leukemic cells play a role in determining remission duration, perhaps because the leukemic cells of the former patients regrow slowly between courses of chemotherapy.

Bone Marrow↗
PubMed1990

A randomized comparison of methotrexate dose and the addition of bleomycin to CHOP therapy for diffuse large cell lymphoma and other non-Hodgkin's lymphomas. Cancer and Leukemia Group B study 7851.

In 1978, Cancer and Leukemia Group B initiated a randomized study to determine the usefulness of the addition of bleomycin and/or high-dose methotrexate to standard therapy for the treatment of certain adult non-Hodgkin's lymphomas. Between 1978 and 1985, 177 patients with diffuse large cell lymphoma (DLCL) and 97 patients with other intermediate-grade non-Hodgkin's lymphoma were randomized to receive therapy with three courses of cyclophosphamide, adriamycin, vincristine, and prednisone (CHOP) every 3 weeks with or without low-dose bleomycin by continuous IV infusion. Responders after three courses were further randomized to 3 weeks of therapy with either high-dose methotrexate (3 gm/m2/week intravenously with leucovorin rescue) or standard-dose methotrexate (30 mg/m2/week orally without rescue). Therapy was concluded with three additional courses of CHOP. Neither the addition of low-dose infusion bleomycin nor the use of high-dose rather than low-dose methotrexate had significant effects on response for patients with DLCL; complete response rates for the four treatment programs ranged from 47% to 51%. Median failure-free survival (FFS) for the entire group of DLCL patients was 12 months; 5-year FFS was 27%. There was no significant effect on FFS from the addition of either low-dose bleomycin to CHOP (5-year FFS: CHOP, 28%; CHOP-B, 26%, P = 0.81), or from the use of different doses of methotrexate (5-year FFS: high-dose, 34%; standard-dose, 33%, P = 0.51). Patients with follicular large cell lymphoma, with or without diffuse areas, had a better FFS (5-year FFS, 47%) than patients with DLCL (5-year FFS, 27%), while the patients with the other histopathologic subtypes of diffuse lymphomas had the poorest FFS (5-year FFS, 16%).

Aged↗
PubMed1990

Shared idiotype expression by chronic lymphocytic leukemia and B-cell lymphoma.

Antiidiotype (Id) antibodies identify unique determinants within the surface immunoglobulin (Ig) that are present on B-cell tumors. Anti-Ids have been used for diagnosis and therapy of B-cell lymphoma and leukemia. A panel of 29 anti-Id monoclonal antibodies (MoAbs) that recognize shared idiotypes (SIds) on B-cell lymphomas was tested for reactivity with both B-cell leukemias and lymphomas. Ten of 40 (25%) cases of chronic lymphocytic leukemia (CLL) reacted with at least one of the 29 anti-SId MoAbs. Three cases reacted with more than one anti-SId MoAb, but there was no repetitive pattern of a single anti-SId MoAb reacting with a large proportion of CLL cases. In contrast, for B-cell lymphoma, in which 11 of 31 (36%) cases reacted, one anti-SId (B4-1) reacted with five of the positive cases; all were diffuse histology. Restricted anti-SId reactivity may lead to important insights into the etiology of certain B-cell lymphomas. In addition, these anti-SIds may obviate the need to develop "tailor-made" antibodies for individual patients.

Antibodies, Monoclonal↗
PubMed1990

Phase II study of MOPLACE chemotherapy for patients with previously treated Hodgkin's disease: a CALGB study.

To further evaluate possible non-cross-resistant regimens in Hodgkin's disease, a phase II trial utilizing antimetabolites and etoposide was initiated by the Cancer and Leukemia Group B (CALGB). Etoposide was included because of its known efficacy in relapsed Hodgkin's disease and to evaluate for synergy with an alkylating agent and vincristine. Cytosine arabinoside and methotrexate were included to evaluate their effectiveness in rapidly growing resistant disease. Forty-two patients with previously treated Hodgkin's disease were entered, of which 37 are evaluable for response and toxicity. All patients had at least 2 prior regimens of chemotherapy and 59% had additional radiation therapy. Complete and partial response was observed in 61%; there were 32% complete responders. Duration of complete response was a median of 8 months (range 2-28+ months). Duration of partial response was 7 months (range 1-17 months). Three patients remain in complete remission at 19, 19, and 28 months. Major toxicity was hematologic with severe or life-threatening toxicity in 54%. There was one patient with a fatal infection. Non-hematologic toxicity, save for nausea and vomiting, was mild and uncommon. There were two fatal and one severe pulmonary toxicities reported in patients who had previous exposure to bleomycin and mediastinal radiation. Three had interstitial pneumonitis and one pulmonary emboli. The interstitial pneumonitis was thought to be drug related. Survival of the entire group is estimated at 61% at 12 months. We conclude that MOPLACE is an effective regimen with an appreciable complete response rate in this heavily pretreated group of patients. Hematologic and pulmonary toxicities are severe and may necessitate dose modifications. The use of etoposide containing combinations requires further study as primary therapy in untreated patients.

Adolescent↗
PubMed1990

Splenectomy in advanced chronic lymphocytic leukemia.

Between February 1972 and February 1989, splenectomies were performed in 30 patients with chronic lymphocytic leukemia (CLL) and three with prolymphocytic leukemia (PLL) at our institution. Indications for splenectomy included anemia and/or thrombocytopenia (hypersplenism) in 31 patients and symptomatic splenomegaly in two patients. Median time from the diagnosis of CLL to splenectomy was 25 months. Twenty (87%) of the 23 patients splenectomized for thrombocytopenia with or without anemia had platelet increments of greater than or equal to 50 x 10(9)/liter. Hemoglobin increments of greater than or equal to 3 gm/dl were noted in 12 (71%) of 17 patients splenectomized for anemia with or without thrombocytopenia. The median duration of platelet response was 18 months for 19 evaluable patients, and the median duration of hemoglobin response was 62 months for 10 evaluable patients. Median survival time from splenectomy was 36 months. Median survival from diagnosis was 103 months for 10 patients with stage III or IV disease at diagnosis and 79 months for 10 patients with stage II. A prospective study of the effect of splenectomy in a larger number of patients with advanced CLL should be considered.

Adult↗
PubMed1990

Interferon therapy of relapsed and refractory Hodgkin's disease: Cancer and Leukemia Group B Study 8652.

A phase II trial of alpha 2b-interferon in patients with relapsed or refractory Hodgkin's disease was conducted by the Cancer and Leukemia Group B. Nineteen patients were eligible for study. These patients had received at least two (median of four) previous chemotherapeutic programs and 79% had received prior radiation therapy. Three patients had undergone intensive chemotherapy and autologous bone marrow transplantation. The treatment regimen consisted of interferon-alpha 2b 10 X 10(6) IU/m2 subcutaneously three times per week. Only limited antineoplastic activity was seen in this heavily pretreated group of patients. There was one partial response and four patients had reduction in measurable disease not meeting the criteria for partial response. The drug was well tolerated. Toxicity was predominantly myelosuppression. Thrombocytopenia was particularly severe in patients with bone marrow involvement. The observed antineoplastic activity, albeit limited, in this heavily pretreated group of patients suggests a potential role for this agent in combination regimens in patients with earlier disease.

Adult↗
PubMed1989

Acute myelogenous leukemia with leukemia cutis. Eighteen cases seen between 1969 and 1986.

Leukemia cutis was documented by biopsy in 18 of 877 patients (2%) with acute myelogenous leukemia (AML) seen at Roswell Park Memorial Institute (Buffalo, NY) between 1969 and 1986. French-American-British (FAB) types included four M2, one M3, ten M4, and three M5. Lysozyme was more consistently detectable in skin sections in our cases than Leu-M1, alpha-1-antitrypsin, alpha-1-antichymotrypsin, or chloroacetate esterase activity. Additional extramedullary sites of involvement were present in 16 patients, including meningeal leukemia in six. Two patients had leukemia cutis preceding bone marrow leukemia. Skin was the initial site of relapse in 11 patients, without marrow relapse, occurring as late as 5.5 years after diagnosis. Most patients in this retrospective series were treated with radiation therapy and/or palliative chemotherapy, and did poorly, with prompt bone marrow relapses and serial skin relapses. Long-term disease-free survival was achieved in the one patient whose skin relapse was treated with whole-body electron-beam radiation therapy in conjunction with reinduction and consolidation chemotherapy. Severe skin toxicity was caused by administration of Adriamycin (doxorubicin) 12 days after electron-beam irradiation in one patient, but was not seen when cytosine arabinoside was administered in doses up to 3 g/m2 in conjunction with radiation therapy. This retrospective review suggests that optimal management of AML involving skin might include whole-body electron-beam irradiation in conjunction with induction or reinduction chemotherapy without anthracyclines, followed by consolidation chemotherapy. Additionally, there should be ongoing surveillance for and treatment of extramedullary disease at other sites, including the meninges.

Antigens, Differentiation, Myelomonocytic↗
PubMed1988

Effect of alpha-interferon therapy on bone marrow fibrosis in hairy cell leukemia.

Iliac crest trephine biopsy specimens from 16 patients treated with recombinant alpha 2-interferon (alpha-IFN) for hairy cell leukemia (HCL) were examined for reticulin and collagen content. These data were compared with the hairy cell index (HCl), the proportion of hairy cells to the overall cellularity of the bone marrow. Specimens were studied immediately before alpha-IFN therapy, at 6-month intervals during, and in six patients 6 months after cessation of therapy. All patients presented with increased bone marrow fibrosis ranging from focally increased reticulin to a diffuse increase in both reticulin and collagen content. This fibrosis was observed to decrease during alpha-IFN therapy inasmuch as the hairy cell population was diminished in the bone marrow in 13 patients. Regression analysis of HCl v bone marrow fibrosis showed a positive correlation (r = .73, P less than .02). Six patients demonstrated a reduction in bone marrow reticulin and collagen to normal levels during alpha-IFN therapy. Two of six patients demonstrated increased bone marrow fibrosis and HCl 6 months after cessation of alpha-IFN therapy. Three of 16 patients exhibited no decrease in bone marrow reticulin content during therapy despite a decreased bone marrow hairy cell population.

Adult↗
PubMed1987

An autopsy study of 1206 acute and chronic leukemias (1958 to 1982).

Autopsy data on 1,206 children and adult patients with acute myelocytic leukemia (AML) (585), chronic granulocytic leukemia (CGL) (204), acute lymphocytic leukemia (ALL) (308), and chronic lymphocytic leukemia (CLL) (109) obtained from 1958 to 1982 were reviewed. This analysis has shown that, whereas the proportion of patients with residual AML at any anatomic site decreased significantly and uniformly over the entire study period, significant corresponding decreases in patients with CGL and ALL occurred only since 1976 and 1978, respectively. No significant corresponding decreases were noted in patients with CLL at any time. Significant decreases were also noted over time in the rates of extramedullary site involvement by AML, CGL, and ALL. Whereas the lymphoreticular organs, kidneys, adrenals, and pituitary were most often involved at autopsy by CLL, the testes, leptomeninges, dura mater, uterus, large bowel, and pancreas were most often involved by ALL. In general, patients with AML and CGL showed the lowest relative rates of involvement of the various organs by leukemia during the 24-year period. Whereas patients with AML and ALL showed significant decreases in the rates of involvement of nearly all anatomic sites during the most recent study periods, those with CGL and CLL showed corresponding decreases in only a few organ sites. The lower rates of organ involvement in patients with AML and ALL attest to the more aggressive eradication of leukemic cells by therapeutic regimens in these diseases over time. In particular, the significant decrease in the rate of meningeal involvement by ALL during the most recent period is probably attributable to central nervous system prophylaxis.

Adolescent↗
PubMed1987

Cyclophosphamide, vincristine, adriamycin, and prednisone (CHOP) with and without intermediate dose methotrexate for the treatment of non-Hodgkin's lymphomas of diffuse histology.

Seventy three patients with disseminated diffuse non-Hodgkin's lymphomas were treated with combinations of cyclophosphamide, vincristine sulfate, prednisone, and doxorubicin with and without 2 weekly doses of oral methotrexate in "intermediate" doses, followed by calcium leucovorin rescue. The addition of methotrexate did not increase the complete remission rate, the remission duration, or the survival (P value = 1.0, 0.74, and 0.78, respectively) in patients who did not have previous chemotherapy treatment. In previously treated patients, the complete remission rate was somewhat higher and the remission duration and survival were longer among those patients treated with the methotrexate containing program; however these differences were not statistically significant (P values = 0.88, 0.81, and 0.46, respectively). There was substantial morbidity and mortality during treatment with both treatment arms, among patients aged more than 60 years.

Adult↗
PubMed1987

Malignant histiocytosis. Complete remission in two pediatric patients.

The experience with the treatment of malignant histiocytosis has been disappointing. Despite modest treatment success with a combination of cyclophosphamide, Adriamycin (doxorubicin), vincristine and prednisone, the overall prognosis remains poor. There are only a few reports of prolonged complete remissions in pediatric patients. The following report describes two children who have had long-term remission with an aggressive combination chemotherapy program that included intrathecal prophylaxis. The chemotherapeutic regimen described merits further evaluation in a larger number of patients.

Adolescent↗
PubMed1987

Mitotic counts in follicular lymphomas.

Increased mitotic activity is associated with significantly shorter patient survival in some of the subtypes of diffuse non-Hodgkin's lymphomas. This study on 105 cases of follicular lymphoma was undertaken to determine the clinical significance of mitotic activity in follicular lymphomas. For each case, two pathologists independently counted mitotic figures in 20 random high-power fields. The difference of the average mitotic counts over 20 high-power fields for the two pathologists showed a Gaussian distribution with a median difference of -0.26 counts per high-power field and a standard error of 0.10 per cent. In 94 cases (91 per cent), the difference was less than two mitotic counts per high-power field, indicating good interobserver agreement. There was a statistically significant difference in mitotic counts between subtypes of follicular lymphoma as well as a gradient among subtypes, with the lowest mitotic activity in the poorly differentiated lymphocytic subtype and highest in the undifferentiated subtype. A multivariate statistical analysis of clinical and pathologic variables showed that mitotic figures were not of prognostic significance.

Humans↗
PubMed1987

High-dose cytosine arabinoside as the initial treatment of poor-risk patients with acute nonlymphocytic leukemia: a Leukemia Intergroup Study.

Sixty-seven patients with newly diagnosed acute nonlymphocytic leukemia (ANLL) who were considered to be poor candidates for treatment with cytosine arabinoside (ara-C)/anthracycline antibiotic therapy were treated with high-dose ara-C (HDara-C) remission induction therapy. Thirty-four of the 67 patients had a hematologic disorder before developing acute leukemia or had a history of exposure to marrow toxins, 23 patients were greater than 70 years old, and 10 patients had medical problems that were felt to be a contraindication to therapy with an anthracycline antibiotic. Forty-two percent of patients entered complete remission (CR), whereas 22% failed to enter remission because of persistent leukemia. Treatment was associated with substantial toxicity varying from nausea and vomiting to irreversible cerebellar toxicity. Thirty-four percent of patients died during therapy. Poor performance status, a low serum albumin, and a low platelet count were associated with death during remission induction therapy, whereas a high pretherapy leukemic cell mass and a large number of residual leukemic cells in the marrow after six days of therapy were associated with treatment failure due to persistent leukemia.

Acute Disease↗
PubMed1987

A randomized trial of high-dose methotrexate versus standard-dose methotrexate following cyclophosphamide, doxorubicin (adriamycin), vincristine, and prednisone with or without bleomycin in the therapy of diffuse large cell lymphoma: preliminary report of Cancer and Leukemia Group B Study 7851.

Between 1979 and 1985, 166 patients with diffuse large cell (histiocytic) lymphoma were randomized to receive therapy with 3 courses of cyclophosphamide, doxorubicin (Adriamycin), vincristine, and prednisone (CAVP), with or without low-dose bleomycin, by continuous iv infusion. Responders were further randomized to 3 weeks of therapy with either high-dose methotrexate (3 g/m2 iv weekly with leukovorin rescue) or low-dose methotrexate (30 mg/m2 orally weekly without rescue). Therapy was concluded with 3 additional courses of CAVP. No significant differences among the 4 treatment programs were observed in complete response rates (ranging from 46% to 51%) or in failure-free survival. Of the 38 relapses that have occurred in patients treated with low-dose methotrexate, 5 included relapse in the central nervous system in conjunction with systemic relapse. However, none of 31 relapses observed in patients receiving high-dose methotrexate have occurred with involvement of the central nervous system. Patients entering this study with "B" symptoms had significantly poorer treatment results than those patients entering study without "B" symptoms.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1986

High-dose cytosine arabinoside in the treatment of preleukemic disorders: a leukemia intergroup study.

Fifteen patients with myelodysplastic/myeloproliferative disorders were treated with high-dose cytosine arabinoside therapy. While severe toxicity was produced in every patient, only two of the 15 patients entered complete remission and two achieved partial remission status. The therapeutic responses were confined to patients who had severe myelofibrosis of apparently recent onset.

Adult↗
PubMed1986

Treatment of early--stages I and II--nodular, poorly differentiated lymphocytic lymphoma.

Twenty-nine patients with Stages I and II nodular, poorly differentiated lymphocytic lymphoma were treated with radiation therapy or radiation therapy plus chemotherapy. Twenty-two patients with Stage I received radiation to the involved field, the other seven with Stage II received total lymphoid radiation. Complete remission was achieved in all 29. There were no differences in remission duration or survival according to treatment modality. Five of 29 (17%) patients relapsed. No relapses were observed after 5 years. Ten patients died; one patient died of lymphoma, and nine others died in continuous complete remission of various other causes. Sixty-six percent of the patients were alive at 74-160 months (median 118 months). Involved field radiation with or without chemotherapy was well tolerated, producing acceptable toxicity. Substantially more toxicity was observed after total lymphoid irradiation and although cures were also achieved, less toxic treatment programs should be investigated. The low rate of relapse observed in early stages of this lymphoma in this and in other studies is suggestive that cures might be achieved in nearly one-half of the patients presenting in early stage.

Adult↗
PubMed1986

Prediction of response of patients with acute nonlymphocytic leukaemia to remission induction therapy: use of clinical measurements.

Two hundred patients with acute nonlymphocytic leukaemia received remission induction therapy consisting of cytosine arabinoside and an anthracycline antibiotic. Analysis of the pretherapy characteristics of the patients demonstrated that patient age was the most important factor in determining whether or not the patient would survive remission induction therapy. Assessment of the characteristics of the bone marrow after 6 d of therapy permitted the recognition of patients who were likely to fail to enter remission because of persistent leukaemia. Taken together, these observations demonstrate that it is possible to identify patients for whom conventional chemotherapy is not likely to be of benefit either because it is too intensive or because it is not intensive enough to produce a complete remission.

Acute Disease↗