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S O'Brien

Publications and source records attributed to S O'Brien.

At least 19 recordsLinked to original sources
PubMed1995

Growth and biologic properties of karyotypically defined subcategories of adult acute lymphocytic leukemia in mice with severe combined immunodeficiency.

Modest progress has been achieved over the past two decades in the treatment of adult acute lymphocytic leukemia (ALL). With modern therapy, response rates are 70% to 80%, but cure rates only average 25% to 30%. Improved in vivo models are needed to investigate the biology of adult ALL and to test new treatment concepts. Fresh leukemia samples from children with ALL have been successfully transplanted into mice with severe combined immunodeficiency (SCID), but no experience exists for adult ALL. We treated SCID mice with 2 mg cyclophosphamide 24 hours before intravenously injecting 20 x 10(6) viable leukemia cells obtained from 13 patients with newly diagnosed adult ALL within five defined phenotype/karyotype subcategories. Ten (76%) of 13 injected leukemia specimens representing all five categories engrafted. The median survival duration of mice was 20 weeks from the time of leukemia cell injection. The rate of engraftment by ALL subset was as follows: two of two T-cell, two of three t(11q23), two of two hyperdiploid, two of three t(9;22), and two of three diploid ALL. The pattern of organ involvement by leukemia in the mice was similar to that of the human disease. Immunohistochemistry and flow cytometry documented the stability of each leukemic phenotype after passage through SCID mice. Cells transplanted from the spleen and bone marrow of mice engrafted with ALL into recipient mice resulted in consistent engraftment. The survival duration in passage groups was similar to that in groups injected with primary cells. The high frequency of engraftment, availability of frozen original specimens, and successful passages in SCID mice provide an in vivo model of adult ALL suitable for further studies of the disease biology and for design of drug studies for the different subtypes of previously untreated adult ALL.

Adolescent↗
PubMed1995

Homoharringtonine therapy induces responses in patients with chronic myelogenous leukemia in late chronic phase.

Homoharringtonine (HHT) is a plant alkaloid with potent myelosuppressive activity and little toxicity when used in a continuous infusion schedule. The antileukemic efficacy of HHT has been shown in acute myeloid leukemia, but has not been investigated in chronic myelogenous leukemia (CML). Seventy-one patients with Philadelphia chromosome-positive (Ph+) CML in late chronic phase (time from diagnosis to therapy longer than 12 months) were treated with a continuous infusion of HHT at a daily dose of 2.5 mg/m2 for 14 days for remission induction and for 7 days every month for maintenance. The median number of courses given was 6 (range, 1 to 35) and 21 patients (30%) continue on treatment. Forty-two of 58 patients (72%) evaluable for hematologic response achieved a complete hematologic remission, and 9 (16%) had a partial hematologic remission. Twenty-two of 71 patients (31%) developed a cytogenetic response; it was major (Ph+ cells less than 35%) in 11 (15%) and complete (Ph+ cells 0%) in 5 (7%). Significant myelosuppression occurred in 39% of induction courses and 9% of maintenance courses. Fever or documented infection was present in 26% of induction courses and in only 8% of maintenance courses. Nonmyelosuppressive toxicity was minimal. Homoharringtonine produced hematologic remissions in the majority of patients with advanced chronic-phase CML. Cytogenetic response occurred in some patients without an association with myelosuppression, and these responses may be prolonged. Future studies investigating homoharringtonine in combination with other active agents in CML, such as interferon, are warranted.

Adult↗
PubMed1995

Interferon maintenance therapy for patients with chronic lymphocytic leukemia in remission after fludarabine therapy.

Many patients with chronic lymphocytic leukemia (CLL) achieve remission after treatment with fludarabine chemotherapy. Most of these patients, however, later experience relapse. In addition, immunologic deficits may persist even in patients in complete remission; lymphopenia, predominantly involving the CD4 population, is universal after fludarabine therapy. We used recombinant alpha interferon (IFN-alpha) maintenance therapy in patients with CLL who achieved remission in response to fludarabine therapy to determine its effect on residual disease, assessed by either bone marrow biopsy or flow cytometry, and on immune restoration. Thirty-one patients were treated with IFN-alpha (3 x 10(6) U by subcutaneous injection three times weekly). Twenty-two patients (71%) were in complete remission (CR) and nine (29%) were in partial remission (PR). Of the 22 patients in CR, 21 (95%) had evidence of residual disease at the start of IFN-alpha therapy. Low CD4 levels were noted in 93% of patients, low IgG levels in 45%, and anergy or hypoergy in 52%. Only one patient in PR achieved a CR on IFN-alpha therapy: the only patient who had had no prior fludarabine but had been treated with chlorambucil and prednisone. All patients in CR with minimal residual disease had persistent disease after IFN-alpha treatment. There were no increases in CD4 counts or IgG levels; three patients with borderline responses to skin testing had an increase in the number of positive tests while on IFN-alpha. The time to progression was no different in patients treated with IFN-alpha than in a historical control group of patients who had received no further therapy after fludarabine. In summary, the use of IFN-alpha maintenance did not eradicate residual disease, restore immune function, or prolong remissions in patients with CLL responsive to fludarabine.

Adult↗
PubMed1995

Topotecan in chronic lymphocytic leukemia.

BACKGROUND: Topotecan is one of a new class of agents that targets topoisomerase I (Topo I) and stabilizes the DNA-topo1 complex, ultimately resulting in cell death. The rationale for the use of topotecan in chronic lymphocytic leukemia (CLL) is based on the finding that levels of Topo I are elevated in the lymphocytes of patients with this disease. METHODS: Twelve patients with CLL were treated with topotecan to assess its clinical efficacy; in addition, DNA-protein cross-linking was measured after exposure of the cells to topotecan, in an attempt to correlate potential anti-CLL effects with this parameter. The median age of the patients was 63 years; all had received prior therapy with fludarabine and four (33%) were resistant to fludarabine. Four patients (33%) had also received therapy with chlorambucil, and three of them were resistant to this agent. Seven patients (58%) were Rai stage I-II and five (42%) were Rai stage III-IV. Topotecan was given as a 30-minute infusion at a daily dose of 2 mg/m2 for 5 days, and courses were repeated monthly. Cells were obtained from the patients before treatment and exposed to 2 microM topotecan or control in vitro. In addition, cells were obtained from patients after they received the first dose of topotecan and protein-bound DNA was measured with the same technique. RESULTS: No patient responded to therapy with topotecan (95% confidence interval, 0-27%). Nonhematologic toxicity was mild and thrombocytopenia occurred in four of eight patients whose conditions could be evaluated. One patients died of myocardial infarction and another died of fungal pneumonia. DNA-protein cross-linking was detected in all nine patients whose cells were assessed in vitro, with levels of cleavable complex ranging from twofold to 7.5-fold that of the control cells. Only two of eight patients with evaluable conditions had increased cross-linking detectable in circulating cells after the first dose of topotecan, which was consistent with the drug's lack of effect in vivo. CONCLUSIONS: Although exposure of cells from patients with CLL to topotecan in vitro at 2 microM resulted in detectable protein-DNA cross-linking, this effect was not seen in patients who received a bolus dose of 2 mg/m2, and no remissions were noted in 12 patients.

Adult↗
PubMed1995

Prolonged survival in chronic myelogenous leukemia after cytogenetic response to interferon-alpha therapy. The Leukemia Service.

OBJECTIVE: To determine whether a cytogenetic response after interferon-alpha therapy in patients with chronic myelogenous leukemia is independently associated with improved survival. DESIGN: Retrospective analysis. PATIENTS: 274 patients with a diagnosis of Philadelphia chromosome-positive chronic myelogenous leukemia in early chronic phase who were treated with interferon-alpha-based programs between 1982 and 1990. INTERVENTION: Therapy with daily subcutaneous interferon-alpha given at 5 x 10(6) U/m2 body surface area (highest dose schedule allowed on studies) or the maximally tolerated lower-dose schedule. RESULTS: Overall, 219 (80%) patients achieved a complete hematologic response and 104 (38%) achieved a major cytogenetic response (< 35% Philadelphia chromosome-positive cells). Estimated median survival was 89 months. Several pretreatment factors were associated with failure to achieve a major cytogenetic response and with worse survival. The existing prognostic models were generally predictive of which patients were likely to achieve a major cytogenetic response (P < or = 0.01) and of survival outcomes (P < or = 0.01). Multivariate analysis identified bone marrow basophilia (P < 0.01) and splenomegaly (P < 0.01) as independent poor prognostic factors for survival. Achievement of a major cytogenetic response, entered as a time-dependent variable while accounting for the other independent factors, was associated with improved survival (P < 0.001). Comparison of survival (dated from 12 months into therapy) with cytogenetic response at 12 months showed that a cytogenetic response was associated with longer survival (P < 0.001). CONCLUSION: Achieving a cytogenetic response with interferon-alpha therapy in patients with chronic myelogenous leukemia was independently associated with improved survival when tested as a time-dependent variable in a multivariate analysis, and this association was confirmed by landmark analysis at 12 months.

Adolescent↗
PubMed1995

Advances in the biology and treatment of B-cell chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in the western hemisphere. Diagnosis and staging of CLL are usually straightforward, but predicting an individual patient's prognosis is still a challenge. Cytogenetic abnormalities provide important prognostic information in CLL and may show its molecular heterogeneity. A search for oncogene abnormalities continues, although no consistent defects have been identified. New agents such as fludarabine produce high complete remission rates and have generated interest in earlier treatment as a first step in a potential cure. Fludarabine also makes autologous bone marrow transplant feasible as a consolidation therapy. Immunologic abnormalities and minimal residual disease persist in most patients in remission. Combining fludarabine with other active agents and devising effective postremission strategies may change the natural history of CLL.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

A three year follow up of self expanding metal stents in the endoscopic palliation of longterm survivors with malignant biliary obstruction.

Effective palliation of malignant biliary obstruction with conventional 10 or 12 French gauge straight polyethylene endoprostheses is limited by stent occlusion, which typically occurs four to five months after insertion. Short term follow up studies of self expanding metal stents (Wallstent, Schneider, UK) in the treatment of patients with malignant biliary obstruction have shown that their use is associated with fewer episodes of stent occlusion compared with plastic stents. There are few data, however, on the longterm patency and durability of metal stents in malignant disease. Between May 1989 and May 1992, metal stents were inserted in 28 patients with malignant bile duct strictures secondary to ampullary tumour (n = 10), pancreatic carcinoma (n = 10), cholangiocarcinoma (n = 7), and porta hepatis nodes from colorectal carcinoma (n = 1). The follow up of these patients until May 1993 is reported with a median follow up of 14.6 months. Twenty two of 28 (78.6%) patients remained free of jaundice or cholangitis. The median period of stent patency was 8.2 months (range 1.0-32.5). Thirteen patients represented with jaundice or cholangitis and endoscopic retrograde cholangiopancreatography showed evidence of stent occlusion due to tumour ingrowth. Successful clearance of metal stents was achieved by balloon trawling, or insertion of a polyethylene stent. In conclusion, metal stents provide improved longterm palliation for patients with malignant biliary strictures with fewer episodes of occlusion compared with conventional stents.

Adult↗
PubMed1995

Idarubicin cardiotoxicity: a retrospective study in acute myeloid leukemia and myelodysplasia.

PURPOSE: To estimate the incidence of idarubicin (IDA)-related cardiomyopathy in acute myeloid leukemia (AML) and myelodysplasia (MDS). PATIENTS AND METHODS: We analyzed a group of 127 AML/MDS patients who received IDA-based induction and postremission or salvage therapy and achieved a complete remission (CR) that lasted > or = 12 weeks for the development of IDA-related congestive heart failure (CHF). CHF was defined as definite if a resting left ventricular ejection fraction (LVEF) of < or = 45% measured by radionuclide ventriculogram (RV) accompanied the clinical diagnosis of CHF, which had to be made during or within 6 months of receiving IDA and for which no other cause was apparent; without RV confirmation, the diagnosis was considered probable. Patients who had RVs performed were evaluated for decreasing LVEF. Older age (> or = 70 years), prior/sequential anthracycline/mitoxantrone (anthraquinone) therapy, and cardiac disease/hypertension were evaluated as risk factors for the development of CHF. RESULTS: One hundred fifteen patients were assessable (median age, 40 years; median dose, 96 mg/m2). Sixty-five had RVs performed during therapy; 43 had risk factors. The probability of IDA-related cardiomyopathy was 5% at a cumulative IDA dose of 150 to 290 mg/m2, with 18 patients receiving doses greater than 150 mg/m2. At a cumulative IDA dose of 150 mg/m2, the probability of a mild or greater asymptomatic decrease probability of a mild or greater asymptomatic decrease in LVEF (> or = 10% to a level < or = 50%) was 18%, whereas the probability of a moderate or greater asymptomatic decrease in LVEF (> or = 15% to a level < or = 45%) was 7%. No patient with asymptomatic LVEF decreases developed CHF. CHF was more frequent in patients with prior/sequential exposure to anthracyclines/mitoxantrone (P = .01). CONCLUSION: In this patient group, IDA-related cardiomyopathy was uncommon with cumulative IDA doses of up to 290 mg/m2. Asymptomatic LVEF decreases were more frequent, but their predictive value for the development of CHF is unclear.

Adolescent↗
PubMed1995

Immune-mediated and unusual complications during interferon alfa therapy in chronic myelogenous leukemia.

PURPOSE: Long-term treatment with interferon alfa (IFN alpha) can produce or exacerbate immune-mediated complications (IMC). The purpose of this study was to analyze the experience with IMC and unusual complications in patients with chronic myelogenous leukemia (CML) undergoing IFN alpha treatment. PATIENTS AND METHODS: The occurrence of IMC and unusual complications was evaluated in patients with Philadelphia chromosome (Ph)-positive CML. RESULTS: Well-documented and clinically evident complications developed in 35 patients after a median of 14 months of IFN alpha treatment. These included 28 (5%) of 581 patients with Ph-positive CML treated with IFN alpha-containing regimens at M.D. Anderson Cancer Center (MDACC) and seven patients referred for opinion or problems who were on other studies. Hypothyroidism occurred in 11 patients (2%), immune-mediated hemolysis in seven (1%), and connective tissue diseases in 11 (2%). Other unusual occurrences included congestive heart failure (CHF; n = 4), porphyria cutanea tarda (PCT; n = 3), membranous glomerulonephritis (MGN; n = 1), and vitiligo (n = 1). IFN treatment was discontinued in 19 patients and the dose was reduced in five. Ten of 11 patients (91%) with immune-mediated hypothyroidism and eight of 11 (73%) with connective tissue diseases had some degree of cytogenetic response at the time of the event. CONCLUSION: Although the frequency of IMC is low, patients treated with IFN alpha should be monitored for signs and symptoms of autoimmunity.

Adolescent↗
PubMed1995

Fludarabine plus doxorubicin in previously treated chronic lymphocytic leukemia.

Based on the activity of fludarabine and doxorubicin in chronic lymphocytic leukemia (CLL), 30 patients received this combination. The median age of these patients was 61 years; median Zubrod performance status was one; median number of prior therapies was three; and median time to treatment was 53 months. Rai stage was 0 for two patients, I/II for 19 patients, and III/IV for nine patients. Prior treatment included fludarabine in 25 patients. In this regimen, fludarabine was administered as 30 mg/m2/d IV x 3 to 10 patients, 25 mg/m2/d IV x 4 to three patients, and to 17 patients as 30 mg/m2/d IV x 4. A 50 mg/m2 IV dose of doxorubicin was given to all patients. The first 17 patients received prednisone 30 mg/m2 x 5 days; however, this was discontinued due to other data demonstrating no therapeutic advantage and increased opportunistic infections when corticosteroids were added to fludarabine. Toxicity consisted primarily of infectious episodes: pneumonia nine, bacteremia one, FUO seven, and minor infection five. Two deaths from pneumonia occurred. Standard guidelines for response were used with the addition of a nodular CR group. Despite prior treatment with fludarabine in the majority of patients, the response rate in the 29 evaluable patients was CR 3%, nodular CR 17%, PR 35%, fail 38% and early death 7%. This combination of fludarabine and doxorubicin is active against CLL and warrants further study.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Cytogenetic and clinical correlates in AML patients with abnormalities of chromosome 16.

Abnormalities of chromosome 16 in AML include del(16q), inv(16) and t(16;16). These three groups have been categorized together and have been associated with high complete remission (CR) and survival rates following Ara-C-based chemotherapy. We have reviewed the 63 AML or MDS patients with an abnormality of chromosome 16 treated at MD Anderson Cancer Center (MDACC) over the past 18 years. Marked differences in survival and remission duration (RD) were noted between the inv(16) or t(16;16) patients and those with del(16q), whose outcome was no better than other M4 AML or MDS patients treated during the same period. Other differences characterizing del(16q) included a lack of CNS relapses, lower incidences of eosinophilia and M4 FAB subtype. Half the inv(16) patients had additional karyotypic abnormalities. The overall survival and remission duration for those patients were no different from those for patients with inv(16) alone, although the probability of remaining in first CR at 2 years was higher in the inv(16) alone group. There was no difference in overall survival for the 45 patients who received HDAC vs those who did not. The incidence of CNS relapse was, however, markedly reduced for the HDAC patients. Eosinophilia did not correlate with improved survival. We conclude that del(16q) confers a different prognosis from inv(16) and t(16;16) and for the purposes of prognostication or treatment recommendations should no longer be categorized with them. Additional karyotypic changes however, which accompany inv(16) in 50% of cases do not influence the overall outcome compared to patients with inv(16) alone.

Acute Disease↗
PubMed1995

A 3-day schedule of fludarabine in previously treated chronic lymphocytic leukemia.

This study was undertaken to determine the efficacy and toxicity of a shorter schedule of fludarabine administration (30 mg/m2 i.v. daily for 3 days every 4 weeks) in patients with previously treated chronic lymphocytic leukemia (CLL). Eighty patients with previously treated advanced (Rai III-IV) (54%) or progressive Rai stage 0-II (46%) were treated. The results of this trial were retrospectively compared with those of previous fludarabine trials using different schedules of administration. The complete response (CR), nodular CR and partial response rates were 10, 15 and 21%. The overall response rate (46%) was slightly lower than prior regimens using a 5-day schedule of fludarabine; however, this difference was not significant. Further evaluation by dual-parameter flow cytometry and immunoglobulin gene rearrangement analysis revealed that minimal residual disease was more common in a 3-day schedule. The overall incidence of infections per treatment course (14%) was significantly lower than that observed on the 5-day or weekly regimens (P < 0.001). The incidence of minor, atypical and viral infections were similar. There was no difference in survival in the various trials. In conclusion, a 3-day schedule of fludarabine in previously treated CLL patients was associated with a lower infection rate and similar survival to a 5-day schedule. These data support the use of a 3-day schedule of fludarabine as a single agent and in combination with other active agents.

Adult↗
PubMed1995

Press coverage of the Cleveland child sexual abuse enquiry: a source of public enlightenment?

BACKGROUND: The objective of this study was to assess national and local newspaper reporting of events considered by a Public Enquiry which investigated a major crisis involving child protection services. The Judicial Enquiry, held in Cleveland, North East England, examined the actions of statutory bodies and the professionals working within them following the diagnosis of suspected sexual abuse in 121 children. METHODS: This is a descriptive study using analysis of legal transcripts and newspaper reports. The data involved a total of 216,360 lines of transcript evidence given by 111 witnesses and lawyers representing them at the Judicial Enquiry which lasted 74 days; together with 344,899 words in reports covering 17 newspapers (seven local and ten national). The main outcome measures were based on the volume and type of newspaper coverage including that for each witness' and lawyer's evidence. A coverage index related the amount of newspaper reporting to the extent of evidence given. RESULTS: The highest coverage of any single day of the Enquiry in both local and national newspapers occurred when Dr Marietta Higgs (one of the two principal paediatricians involved) made her first appearance. However, the highest interest (coverage index) was shown in evidence given by lawyers for the parents and the least in evidence given by public bodies. The evidence of witnesses was used very selectively by the press in emotive headlines to imply blame or support for the main protagonists or their actions. This sustained several lines of reporting: criticism of the doctors and social workers, inter-professional conflicts, damage and wrong-doing to the families and the search for someone to blame. CONCLUSIONS: The Cleveland crisis occupied newspaper headlines in the United Kingdom for more than a year. Much of the newspaper coverage took an adversarial approach which sought to apportion blame and take sides. The press appeared to report negative issues which were newsworthy and did not give a balanced view. Broader policy issues, which formed an important part of the Enquiry report's influence on subsequent child protection legislation, were largely ignored.

Child↗
PubMed1995

Clinical and prognostic significance of trisomy 21 in adult patients with acute myelogenous leukemia and myelodysplastic syndromes.

Trisomy 21 is the second most common trisomy in patients with acute myelogenous leukemia (AML) and myelodysplastic syndromes (MDS). However, its clinical and prognostic significance is not known. We analyzed the records of 1187 consecutive patients with untreated AML or MDS. Thirty-seven (3.3%) had trisomy 21: four (0.3%) as the only cytogenetic abnormality and 33 (2.7%) with other cytogenetic abnormalities (-5 and/or -7 in 15, +8 in nine, t(15;17) in three, inv(16) in three, t(8;21) in one, and hyperdiploid with several other additional chromosomes in two). Twenty-eight patients had AML and nine MDS. No patients had megakaryocytic phenotype (M7), common in patients with constitutional trisomy 21 (Down's syndrome) and AML. Overall, 57% achieved complete remission (CR), with median CR duration of 39 weeks, and median survival of 31 weeks. When patients with additional cytogenetic abnormalities were compared to patients with similar abnormalities but no trisomy 21, their clinical features as well as their CR rate, CR duration and survival were similar, with or without trisomy 21. We conclude that trisomy 21 in AML typically presents in conjunction with other cytogenetic abnormalities, especially -5/-7 and +8 whose presence rather than the presence of +21 dictates the clinical outcome.

Adolescent↗
PubMed1994

Sequential operation of disconnected cerebral hemispheres in split-brain patients.

When two concurrent sensorimotor tasks require separate responses, selection of the first response generally delays selection of the second. Dual-task performance was examined in four patients who had undergone surgical transection of the forebrain commissures including the corpus callosum. One light flash was presented to each visual field in succession, and patients made a choice response to each stimulus with the ipsilateral hand, thereby confining the tasks to separate hemispheres. All four showed dual-task interference very similar to that found with normal individuals. Therefore, still-intact subcortical structures must play a critical role in sequencing response selection processes (the 'dual-task bottleneck'), confirming the distinction between the attentional limitations involved in planning actions and those involved in perceptual analysis.

Brain↗