Biomedical subjects
H Ansari
Publications and source records attributed to H Ansari.
Dyspnoea and a subcutaneous swelling.
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A new prognostic score for survival of patients with chronic myeloid leukemia treated with interferon alfa. Writing Committee for the Collaborative CML Prognostic Factors Project Group.
BACKGROUND: Interferon alfa is a conservative and widely used alternative to bone marrow transplantation in treatment of patients with early chronic myeloid leukemia (CML). A meta-analysis was conducted to develop a reliable prognostic scoring system for estimation of survival of patients with CML treated with interferon alfa. METHODS: Patients treated in prospective studies, including major randomized trials, were separated into learning and validation samples. Cox regression analysis and the minimum P-value approach were used to identify prognostic factors for patient survival and to discover groups in the learning sample with the greatest differences in survival. These findings were then validated by applying the new scoring system to patients in the validation sample. RESULTS: We collected data on 1573 patients who were participants in 14 studies involving 12 institutions; 1303 patients (learning sample, n = 981; validation sample, n = 322) were eligible for inclusion in this analysis, and their median survival time was 69 months (range, 1-117 months). Because two previously described prognostic scoring systems failed to discriminate risk groups satisfactorily, we developed a new scoring system that utilizes the following covariates: age, spleen size, blast count, platelet count, eosinophil count, and basophil count. Among 908 patients with complete data in the learning sample, three distinct risk groups were identified (median survival times of 98 months [n = 369; 40.6%], 65 months [n = 406; 44.7%], or 42 months [n = 133;14.6%]; two-sided logrank test, P< or =.0001). The ability of the new scoring system to discriminate these risk groups was confirmed by analysis of 285 patients with complete data in the validation sample (two-sided logrank test, P = .0002). CONCLUSIONS: A new prognostic scoring system for estimating survival of patients with CML treated with interferon alfa has been developed and validated through use of a large dataset.
Clinical outcome of supratentorial astrocytoma WHO grade II.
OBJECTIVE: There are divergent opinions about the prognostic value of the extent of surgery and of different histological subtypes in supratentorial astrocytomas WHO grade II. METHODS: We reviewed 75 consecutive patients (36 females, 39 males) with supratentorial astrocytomas WHO grade II (59 primary and 16 recurrent tumours) operated on between 1991 and 1995. RESULTS: Gross total resection could be achieved in 40 astrocytomas, subtotal resection (including biopsy) was performed in 35 cases. Histological assessment confirmed 60 fibrillary, 6 gemistocytic, 9 oligo-astrocytic and no protoplasmic astrocytomas. There were no postoperative deaths. Early outcome 6 to 12 weeks after surgery according to the Glasgow Outcome Scale was good in 46 patients, 24 patients had moderate, and 5 had severe neurological deficits. Survival rates 1, 2, 3, and 4 years following surgery were 100%, 96%, 96%, 96% for patients who underwent gross total tumour resection and 86%, 77%, 77%, 64% for patients with subtotal tumour resection. The cumulative recurrence or progression rates after 4 years were 26% after gross total resection and 80% after subtotal resection, and this result is statistically significant. Recurrences after gross total resection or progressions after subtotal resection occurred more often in gemistocytic astrocytomas (40% and 100%, respectively) than in other subtypes. Dedifferentiation to a more malignant tumour seems to be more prominent in the gemistocytic subtype. CONCLUSION: Gross total resection should be the leading therapeutic option for patients with astrocytomas WHO grade II. For the gemistocytic subtype further studies will have to prove whether additional radiotherapy is of any benefit.
Should a platelet limit of 600 x 10(9)/l be used as a diagnostic criterion in essential thrombocythaemia? An analysis of the natural course including early stages.
In order to evaluate the natural history of essential thrombocythaemia (ET), clinical data and prognostic factors of 143 patients with ET were retrospectively analysed (mean observation time 6.1 +/- 4.6 years). In 42 patients the early phase of the disease with initial platelet counts between 250 and 600 x 10(9)/l was assessed. In most early cases, ET was suggested by clinical symptoms (79%) and increased megakaryopoiesis (95%) with abnormal megakaryocytes in bone marrow histology (n = 34) and cytology (n = 5). Other myeloproliferative disorders and reactive thrombocytosis were excluded according to the diagnostic criteria of the Polycythemia Vera Study Group. During follow-up of the 38 early cases not treated cytoreductively at diagnosis, the platelet counts increased to >600 x 10(9)/l in 28 patients (74%) and remained between 450 and 600 x 10(9)/l in 10 patients (26%). In primarily asymptomatic patients (n = 46) with initial platelet counts above (n = 37) and below 600 x 10(9)/l (n = 9) the rates of increase of symptomatic patients were similar at about 7% per year. No influence of the initial platelet count on survival was seen in multivariate analysis of prognostic factors which included all 143 cases. Survival was mainly influenced by the rate of ET-related complications during follow-up (P = 0.002). Analysing the influence of cytoreductive therapy on symptom-free survival, platelet reduction benefited patients under 60 years (19 cytoreductively treated v 65 untreated patients, P = 0.075). The results demonstrate the possible clinical relevance of the early stages of ET and suggest that the features of pathologic megakaryopoiesis in the bone marrow are a more reliable diagnostic criterion than a definite platelet limit. Therefore, further therapeutic studies should include all stages of the disease and all age groups.
Comparative analysis of the impact of risk profile and of drug therapy on survival in CML using Sokal's index and a new score. German chronic myeloid leukaemia (CML)-Study Group.
Survival times in chronic myeloid leukaemia (CML) may vary widely depending on the risk profiles of patients. This fact is frequently not, or not sufficiently, considered in evaluating survival in CML, and some studies do not report risk profiles. Therefore we analysed the relative impact of risk profile and therapy on survival using the median survival times of therapy groups and of risk groups of the three-arm randomized German CML Study I (interferon alpha v hydroxyurea v busulphan; median survival times 65 v 56 v 45 months, n = 490, median observation time 70.4 months). The impact of risk profile (Sokal) on survival as determined by the survival difference between high and low risk patients (40 months) was twice the maximum survival difference between treatment groups (20 months). A similar ratio was obtained after stratification for therapy and for risk profile. Since Sokal's index has been reported to prognostically discriminate IFN-treated patients less well than chemotherapy-treated patients, a new score with better discrimination of IFN-treated patients was also used. The results were similar for both scores. We conclude that the risk profile at diagnosis is still more important for survival of CML patients than therapy. Therefore patients should be stratified according to risk profile for comparisons of survival times between studies and treatment arms.
The hydrophobic pocket of cyclophilin is the binding site for the human immunodeficiency virus type 1 Gag polyprotein.
Completion of an early step in the human immunodeficiency virus type 1 (HIV-1) life cycle requires incorporation into virions of the cellular peptidyl-prolyl isomerase cyclophilin A (CyPA) by the Gag polyprotein. Elucidation of the biochemical role of CyPA would be aided by a detailed analysis of the genetic requirements for the formation of the Gag-CyPA complex; previous experiments have demonstrated the requirement for a critical proline and the immediately preceding glycine, located within the capsid domain of Gag, but nothing is known about the necessary CyPA residues. Cyclophilins possess a hydrophobic pocket where proline-containing peptide substrates and the immunosuppressive drug cyclosporine A bind. In this study, we engineered five CyPA mutations, each of which alters a residue that contributes to the hydrophobic pocket. Compared with the wild-type protein, all of the mutants drastically reduced CyPA binding to HIV-1 Gag and similarly inhibited CyPA incorporation into virions. In addition, we demonstrated that previously reported differences between the Gag-binding properties of CyPA and CyPB are due to adventitious association involving residues in the signal sequence of CyPB and that the core domain of CyPB interacts with Gag in a fashion which is indistinguishable from that of CyPA. These studies indicate that, as with other proline-containing peptides or cyclosporine A, HIV-1 Gag directly contacts residues in the hydrophobic pocket of CyPA.
Randomized study of the combination of hydroxyurea and interferon alpha versus hydroxyurea monotherapy during the chronic phase of chronic myelogenous leukemia (CML Study II). The German CML Study Group.
It is the long-term goal of the German CML Study Group and of the Süddeutsche Hämoblastosegruppe (SHG) to improve survival of patients with chronic myelogenous leukemia (CML). In a first randomized study (CML Study I) monotherapies with hydroxyurea or interferon alpha (IFN-alpha) were compared with a standard busulfan regimen with regard to duration of the chronic phase and survival. The main results of this study were published, 1-3 and a long-term follow up is planned. In a second randomized study the effect of the combination of IFN-alpha and hydroxyurea versus hydroxyurea monotherapy on survival is being investigated. This paper provides a first preliminary report on the study concept, patient recruitment, state of documentation and initial patients' characteristics 9 months after closure of the study.
Analysis and validation of prognostic factors for CML. German CML Study Group.
The analysis and validation of prognostic factors is a decisive prerequisite with regard to the development and application of risk-adjusted therapies. Among others, the Sokal index 1 and Kantarjian's new staging system 2 were scores set up to assess the survival of every patient individually. By means of 504 Ph- and/or bcr-abl-positive patients of the German CML study I, we tried to validate both scores mentioned above. Whereas Kantarjian's staging system provided rather unsatisfactory results, the discrimination of different risk groups was more promising with respect to the Sokal index. Still, concerning the differentiation between risk groups for the interferon-alpha (IFN-alpha) treated patients of the German study I, the Sokal index also failed. Hence, we applied Cox stepwise regression technique and identified three prognostic factors for the IFN-alpha treated patients, i.e. eosinophils, erythroblasts (both in peripheral blood), and extramedullary manifestations. We developed our own score and found an encouraging 5-y survival rate of 90% (95% confidence interval (CI) 76-100%) for a certain low-risk group of 41 out of 120 IFN-alpha treated patients. With the need to validate our score and, if possible, not only to confirm the above result but also to identify other particular patient groups, we launched the European Prognostic Factors Project (E.P.F.P.). Within this project, our special interest will be dedicated to patient groups who might also benefit from a bone marrow transplantation.
Graft-versus-leukemia effect of donor lymphocyte transfusions in marrow grafted patients.
The immune reactivity of allogeneic lymphocytes plays a major role in the control of leukemia after bone marrow transplantation. In patients with recurrent leukemia after marrow transplantation, chimerism and tolerance provide ideal conditions for adoptive immunotherapy with donor lymphocytes. We studied the effect of donor lymphocyte transfusions on acute and chronic leukemia in relapse after bone marrow transplantation. One hundred thirty-five patients with chronic myeloid leukemia (CML) (N = 84), acute myeloid leukemia (AML) (N = 23), acute lymphoblastic leukemia (ALL) (N = 22), myelodysplastic syndrome (MDS) (N = 5), and polycythemia vera with osteomyelofibrosis (PCV) (N = 1) were treated with transfusions of donor lymphocytes. Patients were monitored for response of leukemia, including in CML, the use of the polymerase chain reaction for bcr/abl mRNA transcripts and for the occurrence of graft-versus-host disease (GVHD) and myelosuppression. Complete remissions were induced by donor lymphocyte transfusions in 54 patients with CML (73%) and in the patient with PCV; complete remissions were also induced in five patients (29%) with AML and a patient with MDS. In contrast, ALL did not respond to adoptive immunotherapy with donor lymphocyte transfusions. Remissions were durable in patients treated for CML in chronic phase (probability of remission: 87% at 3 years). Lymphocyte transfusions were also given to 18 patients with ALL, AML, MDS, and transformed phase CML who were in remission after chemotherapy. These remissions were not durable. Fifty-two patients (41%) developed GVHD of grade 2 or more, and 41 patients (34%) showed signs of myelosuppression. Seventeen patients died without leukemia, 14 patients with GVHD and/or myelosuppression. Donor lymphocyte transfusions exert strong effects against myeloid forms of leukemia and induce durable remissions in CML.
Roferon (rIFN-alpha 2a) is more immunogenic than intron A (rIFN-alpha 2b) in patients with chronic myelogenous leukemia.
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New perspectives with interferon alpha. The German CML study group experience.
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Therapeutic progress and comparative aspects in chronic myelogenous leukemia (CML): interferon alpha vs. hydroxyurea vs. busulfan and expression of MMTV-related endogenous retroviral sequences in CML. German CML Study Group.
In summary, it can be expected that the availability of unrelated donors will increase the number of CML patients that can be treated curatively with allogeneic BMT. Hydroxyurea has replaced busulfan as first line treatment in CML since it prolongs survival. Ongoing randomized studies comparing IFN-based treatment regimens with standard chemotherapy or IFN-monotherapy probably will answer the question whether IFN can cure a small percentage of CML patients and whether this small percentage can be increased by additional chemotherapy. The present attempts to improve prognostic scores and to apply them to early treatment decisions will allow treatment adaptation more individually. The implications of endogenous retroviral sequences expressed in CML cells are not known now, but may be far reaching.
Chronic myelogenous leukemia: progress in chemotherapy and evaluation of prognostic score 1. The German CML Study Group.
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Prophylaxis of first variceal bleeding.
Surgical, endoscopic and pharmacological treatment options are available for prophylaxis of first upper intestinal haemorrhage in cirrhotic patients. Randomized controlled trials have revealed that a prophylactic portocaval shunt operation should not be performed because its beneficial effect on the bleeding rate is outweighed by a slightly increased mortality. Prophylactic portal non-decompressive surgery (mainly gastro-oesophageal vascular disconnection) has been shown to reduce the bleeding rate and mortality in Japanese cirrhotic patients. However, further trials in different populations must confirm this positive effect. beta-blockers have fewer side-effects and are probably more effective for prophylaxis of the first bleed than sclerotherapy, but survival is only marginally influenced. Nadolol is preferable to propranolol. The effect of sclerotherapy is in part related to the technical experience of the physician. Although sclerotherapy has only minor effects on the bleeding rate, it is associated with a trend towards a prolonged survival. This may be caused by non-specific effects. On the basis of the published trials, only preliminary recommendations can be given. Prophylactic treatment may be useful in cirrhotic patients who are at high risk of bleeding. Life quality may be improved with continuous beta-blocker treatment. Some studies suggest that alcoholics with large varices may also profit from regular prophylactic sclerotherapy performed by experienced physicians.
Variceal injection sclerotherapy.
With the development and widespread use of flexible endoscopes, injection sclerotherapy of oesophageal varices has advanced beyond the early stages. Although slightly different techniques and different sclerosants are used, the results are not strikingly different. The cumulative rate of adverse effects is in the range of 20 to 40%, with a procedure-related mortality of around 1 to 2%. Sclerotherapy is the best available treatment for haemostasis of acute oesophageal variceal bleeding. However, as a long-term therapy it is less effective in the prevention of recurrent gastrointestinal bleeding events, since obliteration of all varices often takes several months. Furthermore, extra-oesophageal bleeding is not amenable to sclerotherapy. Thus, if repeated injections fail to prevent recurrent bleeding, other options such as shunt surgery, transection, chronic medical portal decompression with beta-blockers or even liver transplantation should be considered according to the needs of the individual patient. Prophylaxis of first variceal haemorrhage was beneficial in selected patients with a high bleeding risk. It cannot, however, be generally recommended at present.
Prognostic value of the intravenous 14C-aminopyrine breath test compared to the Child-Pugh score and serum bile acids in 84 cirrhotic patients.
The prognostic value of the intravenous 14C-aminopyrine breath test (ABT) in liver cirrhosis was compared to that of the well-established multiparametric Child-Pugh classification and that of serum bile acids, an endogenous parameter of liver function for which a prognostic value in patients with liver cirrhosis has been demonstrated previously. 84 patients with liver cirrhosis were studied. 32 of the patients died during the observation period. Survival was analyzed for periods of 3, 6 and 12 months after examination. For all chosen observation periods, the Child-Pugh score was of prognostic value. ABT gave prognostic information for periods of 6 and 12 months of survival, but was by far inferior to the Child-Pugh score. Serum bile acids in our population did not yield prognostic information at any time interval studied. We conclude that in our group of cirrhotic patients, the prognostic value of the Child-Pugh classification was by far superior to quantitative liver function tests in predicting survival.
Prediction of variceal hemorrhage in cirrhosis: a prospective follow-up study.
Endoscopic, clinical, and laboratory parameters including presence of varices in the gastric fundus, red color sign, diameter and number of variceal columns, platelet count, and the Child status were assessed in 109 patients with cirrhosis and esophageal varices without previous variceal bleeding. During a mean follow-up period of 21 months, the predictive values of these parameters with regard to first bleeding incidence and mortality rate were studied. The incidence of bleeding was 29%, and the mortality rate 46%. Endoscopic criteria (presence of varices in the gastric fundus, presence of the red color sign, and size of the largest varix) as well as alcoholic etiology of cirrhosis showed a significant positive correlation with the bleeding incidence but not with mortality. Contrary to this, two factors of the Child classification (encephalopathy and ascites) and age positively correlated with mortality but not with the bleeding incidence.