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Biomedical subjects

R Powles

Publications and source records attributed to R Powles.

At least 55 records · Page 3Linked to original sources
PubMed2000

Autologous bone marrow transplantation for childhood acute lymphoblastic leukaemia in second remission - long-term follow-up.

From 1984 to 1996, 31 consecutive children without sibling donors, aged 5-19 years (median 8) with acute lymphoblastic leukaemia (ALL) in second complete remission (CR), received unpurged autologous bone marrow transplantation (ABMT) after melphalan and single fraction total body irradiation (TBI). ABMT was performed using fresh unmanipulated marrow harvested after standard reinduction and consolidation therapy 2-11 months (median 5) after relapse. With a median survival of 2.9 years the probability of survival for all patients in continuing second CR was 45.1% (95% CI, 24%-62%) after 5 years. Regimen-related and non-leukaemia mortality was 7% (95% CI, 2%-26%). The longest time to second relapse from ABMT was 3.1 years. Pituitary and gonadal dysfunction requiring hormonal replacement therapy occurred in the majority of long-term survivors. Twelve patients developed cataracts. ABMT with melphalan/single fraction TBI has proved an effective anti-leukaemia treatment with low regimen-related mortality but significant long-term morbidity. The current approach of allogeneic BMT from an unrelated donor when no sibling donor is available, following conditioning with cyclophosphamide/ fractionated TBI has resulted in a reduced relapse rate and improved short-term overall survival in the treatment of relapsed childhood ALL. However, long-term results are awaited.

Adolescent↗
PubMed2000

Acute lymphoblastic leukaemia-type intensive chemotherapy to eliminate minimal residual disease after high-dose melphalan and autologous transplantation in multiple myeloma - a phase I/II feasibility and tolerance study of 17 patients.

Aiming to target the minimal residual disease in patients with multiple myeloma, a phase I/II single centre study was undertaken for feasibility and tolerance of intensive acute lymphoblastic leukaemia consolidation chemotherapy (ALL-IC) as part of a strategy for post-transplant consolidation targeted at pre-B cells. Seventeen newly diagnosed patients with myeloma (median age 55 years; 30-65) were initially treated with courses of infused cyclophosphamide, vincristine, adriamycin and methylprednisolone (C-VAMP) followed by melphalan 200 mg/m2(HDM) and peripheral blood stem cell rescue (PBSC). Forty-seven percent were in CR and the rest in PR after HDM. ALL-IC consisted of vincristine, daunorubicin, etoposide, cytarabine, 6-thioguanine and prednisolone given over 5 days. All patients became neutropenic (<0.5 x 109/l) at a median of 10 days (4-18) and one of the 17 patients (5.8%) died 15 days post ALL-IC of sepsis. A further four have died of relapse with an overall survival (OS) of 67% at 4 years. Two of nine patients in PR at the time of ALL-IC achieved CR. Matched-pair analysis of 34 control patients shows no difference for OS and event-free survival between ALL-IC and controls. We conclude that ALL-IC given to myeloma patients after HDM/PBSC is as safe as when used in ALL and warrants further assessment in randomised trials for myeloma.

Adult↗
PubMed2000

A low CD34+ cell dose results in higher mortality and poorer survival after blood or marrow stem cell transplantation from HLA-identical siblings: should 2 x 10(6) CD34+ cells/kg be considered the minimum threshold?

We studied the effect of the CD34+ cell dose on transplant-related mortality (TRM) and survival in 39 patients randomized to receive lenograstim-mobilized PBSCT (n = 20) or BMT (n = 19) from HLA-identical siblings. Both marrow and blood were harvested, and one infused in a double-blind fashion. The median nucleated (7.0 vs 3.2 x 10(8)/kg; P < 0.0001), CD34+ (3.7 vs 1.5 x 10(6)/kg; P = 0.002), CFU-GM (42 vs 19 x 10(4)/kg; P = 0.002), and CD3+ (1.9 vs 0.3 x 10(8)/kg; P < 0.0001) cell doses with PBSCT were higher. Thirteen patients (6 BMT and 7 PBSCT) experienced TRM at 15-733 days (median 57); 10 of 20 receiving <2 x 10(6) CD34+ cells/kg compared with three of 19 receiving > or =2. Eight of 20 patients receiving <2 x 10(6) CD34+ cells/kg are alive compared with 14 of 19 receiving > or =2. In Cox analysis, CD34+ cell dose > or =2 x 10(6)/kg was associated with lower TRM (RR 0.2, P = 0.01), and higher overall (RR 3.7, P = 0.01) and event-free (RR 3.2, P = 0.02) survival. Other cell populations and the source of stem cells did not affect TRM or survival. We conclude that 2 x 10(6) CD34+ cells/kg may be the ideal minimum cell dose for allogeneic transplantation although lower doses do not preclude successful therapy. Since the likelihood of obtaining this threshold CD34+ cell number is significantly greater from blood than marrow, PBSCT may be preferable to marrow for allografts from HLA-identical siblings.

Adolescent↗
PubMed2000

Secondary myelodysplastic syndrome/acute myeloid leukaemia following mitoxantrone-based therapy for breast carcinoma.

Of 1774 patients with breast cancer given mitoxantrone (MTZ) with methotrexate (n = 492) or with methotrexate and mitomycin C (n = 1282), nine developed MDS/AML after a median of 2.5 years. Median duration of survival from diagnosis of MDS/AML was 10 months and six patients died. The crude incidence of developing MDS/AML after MMM or MM chemotherapy was 15 per 100,000 patient years follow-up, while the actuarial risk was 1.1% and 1.6% at 5 and 10 years respectively. MTZ-based regimens carry a 10 x higher risk of subsequent MDS/AML compared to that seen in the general population.

Acute Disease↗
PubMed1999

Long-term outcome of adult acute leukemia patients who are alive and well 2 years after autologous blood or marrow transplantation.

We studied the long-term outcome of 87 adults with acute leukemia (age 15-59 years at transplant, median 27; 44 myeloid, 42 lymphoblastic, one biphenotypic) who were alive in continuous remission 2 years after a marrow (n = 74) or blood stem cell (n = 13) autograft. Nine relapsed 25-50 months (median 38) after transplantation. Five relapses were straightforward with no karyotypic or morphologic evolution of the original disease. Four recurrences were unusual, with development of myelodysplasia (n = 3) or myeloproliferative disease (n = 1). Five patients died of relapsed disease and four are still alive. Two patients died of complications related to the transplant, and one of ischemic heart disease. Seventy-nine patients (91%) are alive in remission 24-149 months (median 67) after transplantation (75 in continuous remission and four after further therapy) with Karnofsky scores of 80-100% (median 100%). The 8-year probabilities of survival, toxic death, and relapse (from the 2-year mark) are 89%, 3% and 12%. Eleven (12%) survivors had creatinine levels of >110 micromol/l (one more than double), and 14 (16%) had bilirubin levels of >17 mmol/l (one more than double) at the last follow-up. None of the following factors was found to be predictive for survival, non-relapse death, or relapse from the 2-year mark in multivariate analysis: age, sex, type of leukemia, disease stage, diagnosis, conditioning, origin of cells, and nucleated cell dose. We conclude that adult patients with acute leukemia who are alive and well 2 years following an autograft have a high probability of being cured, and the incidence of long-term liver and kidney dysfunction measured by serum bilirubin and creatinine is low.

Acute Disease↗
PubMed1999

Complete remission rate and outcome after intensive treatment of 177 patients under 75 years of age with IgG myeloma defining a circumscribed disease entity with a new staging system.

Because the presence of IgG paraprotein in the blood is clear cut, it makes IgG myeloma a more circumscribed disease than myeloma as a whole in which to study treatment efficacy, particularly relating to complete remission (CR). Between May 1989 and December 1997, 177 consecutive patients with IgG myeloma who were <75 years old were seen, of whom 153 entered a sequential therapy (ST) programme of initial courses of C-VAMP infusional chemotherapy (IC), high-dose treatment (with or without stem cell rescue) (119 patients) and maintenance interferon (87 patients). 74/153 (48.4%) patients entered CR. Median overall survival (OS) and event-free survival (EFS) were 4.9 and 2.1 years, respectively. Multivariate analysis at presentation showed OS was significantly prolonged for beta2M <2.7 mg/l and age 8.5 g/dl predicted for longer EFS. For CR patients, age <median 51 years, absence of Bence-Jones proteinuria (BJP), male sex and white blood cells (WBC) <7 x 109/l predicted for a longer OS. Longer length of first CR was predicted by absence of BJP at presentation (P = 0.03) and fewer than five courses of IC (P = 0.02) to attain CR. We have therefore been able to refine the use of ST in IgG myeloma, redefine CR as a 'macro' endpoint, and propose a new staging system for IgG myelomas. Analysis of 41 comparable IgA patients showed IgG to be a distinct entity.

Adult↗
PubMed1999

Long-term outcome of adult acute leukemia patients who are alive and well two years after allogeneic bone marrow transplantation from an HLA-identical sibling.

We studied the long-term outcome of 136 adults with acute leukemia (age 15-48 years at transplant, median 28; 112 myeloid, 22 lymphoblastic, 2 undifferentiated) who were alive in continuous remission two years after allografting from HLA-identical sibling donors. Six relapsed 25-46 months (median 30) after BMT. Fourteen (10%) died of non-relapse causes (12 transplant-related and 2 unrelated) 24-140 months (median 73) after BMT; mainly due to complications of chronic GVHD (8 infections, 3 secondary malignancies). One hundred and seventeen (86%) patients are alive in remission 25-226 months (median 103) after BMT; 116 (85%) in continuous remission. Eight survivors have symptomatic chronic GVHD requiring therapy (Karnofsky scores 60-90%, median 80%). The majority of those without chronic GVHD have Karnofsky scores of 100%. The 10-year probabilities of survival, toxic death, and relapse (from the 2-year mark) are 81%, 13%, and 5%. Twenty-two (19%) survivors had creatinine levels of > 110 mumol/L (one more than double), and 11 (9%) had bilirubin levels of > 17 mmol/L (one more than double) at the last follow-up. The absence of chronic GVHD at the 2-year mark (RR 3.5, P = .004), and female sex (RR 2.9, P = .04) influenced overall survival favorably, and the absence of chronic GVHD at the 2-year mark (RR 8.1, P = .001) influenced toxic death favorably. We conclude that patients with acute leukemia who are alive and well without chronic GVHD two years following an allograft have a high probability of being cured, whereas patients with active chronic GVHD requiring immunosuppression continue to be at risk of non-relapse death. The incidence of long-term liver and kidney dysfunction measured by serum bilirubin and creatinine is low.

Acute Disease↗
PubMed1999

Long-term follow-up of relapsed acute leukemia treated with immunotherapy after allogeneic transplantation: the inseparability of graft-versus-host disease and graft-versus-leukemia, and the problem of extramedullary relapse.

Long-term outcome of 23 acute myeloid (AML, n=16) or lymphoblastic (ALL, n=7) leukemia patients who had received immunotherapy for treatment of persistent or recurrent disease 1.5-26 (median 4) months after allogeneic transplantation was studied to determine eventual survival. Immune manipulation comprised donor leukocyte infusion (n=18), interferon-alpha2b and/or interleukin-2 (n=15), and cyclosporine withdrawal (n=11) in various combinations. Graft-versus-host disease (GVHD) developed in 12 patients. Thirteen of 20 evaluable patients responded; 6 relapsing again. Eight patients died of toxicity, and 10 of progressive disease at 3-206 weeks (median 11). Five patients (3 AML, 2 ALL) are alive in remission with GVHD 2-46 months (median 23) after immunotherapy with Karnofsky scores of 70-100% (median 80). The overall survival of the whole group is 1-206 weeks (median 12), with an actuarial survival of 22% at 2 years. The development of GVHD was associated with superior survival in multivariate analysis (P=.007). Seven patients received immunosuppression because of the severity of GVHD (grade III/IV acute or extensive chronic): 3 died of GVHD, 3 improved but relapsed concomitantly, and 1 is alive in remission with extensive chronic GVHD. Four episodes of extramedullary relapse (granulocytic sarcomas) were seen in 3 patients with AML whose marrow remained in remission. We conclude that GVHD appears to be inseparable from graft-versus-leukemia in relapsed acute leukemia patients undergoing immunotherapy with a high proportion of patients dying due to toxicity or progressive disease, and isolated extramedullary relapse seems to be unusually common.

Acute Disease↗
PubMed1999

The impact of karyotype on remission rates in adult patients with de novo acute myeloid leukemia receiving high-dose cytarabine-based induction chemotherapy.

One hundred and twenty-eight patients aged 15 years or over (median 34) with de novo acute myeloid leukemia (AML) received 2- or 3-drug induction chemotherapy comprising 5 days of daily high-dose cytarabine (2 g/m2 q12h) and etoposide (100 mg/m2), without (n=62, 1985-90, protocol BF11) or with (n=66, 1990-97, protocol BF12) daily 5 mg/m2 anthracycline (61 idarubicin, 5 mitoxantrone). Twelve patients with t(15;17) were not included. Evaluable karyotypes were obtained in 110 (86%): 30 (27%) favorable, 60 (55%) intermediate, and 20 (18%) adverse. Three patients dying during chemotherapy were inevaluable. Eighty-four (67%) patients remitted with one cycle, and the overall complete remission (CR) rate was 72%. CR rates were comparable for patients with and without evaluable karyotypes. CR rates with BF11 (64% after one cycle; 72% overall) and BF12 (70% after one cycle; 72% overall) were comparable (P=.4 and 1.0 respectively). CR rates after one cycle (86%, 61% and 55%; P=.03) as well as overall CR rates (90%, 69% and 55%; P=.02) were significantly different for patients with favorable, intermediate and adverse karyotypes respectively. In Cox analysis, the karyotype was the only factor found to influence CR independently. We conclude that the karyotype of the leukemic clone is the most important determinant of response to high-dose cytarabine-based induction chemotherapy in AML. The addition of idarubicin to high-dose cytarabine and etoposide does not appear to improve CR rates. A different treatment strategy may be needed to improve CR rates for patients with non-favorable karyotypes.

Acute Disease↗
PubMed1999

Metastatic extramedullary plasmacytoma of the lung.

Extramedullary plasmacytomas (EMP) comprise 4% of all plasma cell neoplasms and commonly in the upper airway or digestive tract but rarely develop in the lungs. We present a case of primary pulmonary plasmacytoma in an 89 year old man, presented as a hilar mass with associated intrathoracic and extrathoracic lymph node metastases, but without evidence of myeloma. Treatment options for EMP include surgery, surgery and radiotherapy, surgery and chemotherapy or chemotherapy alone. Local recurrence rate is reported as 10-30%, with 17-48% progressing to multiple myeloma and median survival being 63-101 months. In view of the advanced age of this patient, who was initially treated unsuccessfully with intravenous cyclophosphamide and subsequently with two cycles of VAMP chemotherapy with good resolution of his disease, he is undergoing regular follow-up only.

Aged↗
PubMed1998

Identification of patients who may benefit from prophylactic immunotherapy after bone marrow transplantation for acute myeloid leukemia on the basis of lymphocyte recovery early after transplantation.

Two hundred and one patients (median age, 29 years) with acute myeloid leukemia (AML) underwent bone marrow transplantation (BMT) from HLA-identical sibling donors after conditioning with melphalan-total-body irradiation (TBI) (57%), cyclophosphamide-TBI (35%), or chemotherapy alone (8%). Graft-versus-host disease (GVHD) prophylaxis included cyclosporine alone (68%), cyclosporine-methotrexate (26%), or T-cell depletion (6%). The probability of relapse was calculated as a function of the absolute lymphocyte count (10(9)/L) on days 27 to 30 posttransplant (<0.1 v >/=0.1, <0.2 v >/=0.2, and <0.3 v >/=0.3). In each of these 12 comparisons, the probability of relapse was higher for the group with the lower lymphocyte count. Because the difference was most significant (P = .004) for an absolute lymphocyte count of <0.2 on day 29 (3-year relapse probability, 42%) versus >/= 0.2 (16%), this variable was included in a Cox model to determine factors independently affecting relapse. Multivariate analysis showed that conditioning regimens other than melphalan-TBI, a low lymphocyte count on day 29, French-American-British (FAB) subtypes M4-7, and a nucleated cell dose of > 2.42 x 10(8)/kg was associated with a higher risk of relapse. We conclude that slow lymphocyte recovery after allogeneic BMT, to < 0.2 x 10(9)/L 29 days in this analysis, appears to be associated with a higher risk of relapse in patients with AML. This group of patients may benefit from posttransplant immune manipulations such as abbreviated GVHD prophylaxis, or donor cell or cytokine administration to enhance graft-versus-leukemia reactions to reduce relapse.

Acute Disease↗
PubMed1998

Clinical effects of human macrophage inflammatory protein-1 alpha MIP-1 alpha (LD78) administration to humans: a phase I study in cancer patients and normal healthy volunteers with the genetically engineered variant, BB-10010.

BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha (hMIP-1 alpha) with improved pharmaceutical formulation properties. Although initially described as a pro-inflammatory cytokine, it is now recognised that hMIP-1 alpha has additional effects on haemopoietic stem cell cycling and on human immunodeficiency virus uptake by macrophages. In view of the potential clinical utility of the molecule, we have embarked on a clinical trials programme to evaluate the safety, tolerability and haematological effects of BB-10010. We now report the results of two phase I clinical studies in which 49 subjects (9 patients with advanced breast carcinoma and 40 normal healthy volunteers) received escalating doses of BB-10010, from 0.1 to 300 micrograms/kg using the subcutaneous (s.c.) or intravenous route (i.v.) of administration. Treatment was associated with a dose-related increase in monocyte count which peaked at 200% of steady-state levels and was preceded by an acute, short-lived, monocytopenia, 50-100% of baseline. no measurable effects were noted on other leucocyte subsets or on circulating progenitor cell numbers. In all cases, BB-10010 was extremely well tolerated with no significant toxicity observed at any dose level and a maximum tolerated dose was not defined. Pharmacokinetic analysis revealed that serum concentrations of BB-10010 were detectable using doses of > or = 10 micrograms/kg i.v. or > or = 30 micrograms/kg s.c., and that a single s.c. injection resulted in sustained plasma levels over a 24 h period. These preliminary studies have confirmed the safety and tolerability of BB-10010 using a dose range up to 300 micrograms/kg. Further clinical studies are ongoing to determine the biological effects and to investigate the potential myeloprotective properties using a variable dose range and schedule of BB-10010 in combination with cytotoxic chemotherapy.

Adult↗
PubMed1998

Red cell fragmentation (schistocytosis) after bone marrow transplantation.

Red cell fragmentation is often the earliest sign of thrombotic microangiopathy. Days +14, +28 and +42 blood films from 58 allograft and 32 autograft recipients were reviewed blind to determine the incidence and severity of schistocytosis (the number of fragmented red cells per 1000 red cells expressed as a percentage). Schistocytosis was graded as mild (<1%), moderate (1-1.9%) or severe (> or =2%). Schistocytes were seen in 99% of day 14 films (0.1-3.0%, median 0.4%), 97% of day 28 films (0.1-3.2%, median 0.4%), and 98% of day 42 films (0.1-4.3%, median 0.5%). Nine patients (10%) had severe fragmentation and 20 patients (22%) had moderate fragmentation at some time or the other. The difference in the extent of fragmentation between the days was not significant. Allogeneic BMT was associated with more extensive fragmentation than autologous transplantation on day 28 (P = 0.008) and day 42 (P = 0.02). Age, conditioning regimen and diagnosis had no influence. None of the patients followed-up for 6 months after transplant developed full-blown thrombotic microangiopathy. The occasional patient showing mild clinical and laboratory features of hemolysis responded well to adjustment of fluid balance and cyclosporine dose where applicable. Our data indicate that mild red cell fragmentation is a common morphologic finding after transplantation with no clinical significance in the absence of other clinical and laboratory findings suggestive of thrombotic microangiopathy, although patients with moderate or severe fragmentation should be monitored closely.

Adolescent↗
PubMed1998

Familial acute myeloid leukaemia: four male members of a single family over three consecutive generations exhibiting anticipation.

A kindred with familial acute myeloid leukaemia (AML) is described displaying the concept of anticipation which refers to increased disease severity and/or earlier age at onset with succeeding generations. The affected individual in the first generation was the father (aged 34 years at diagnosis) of two affected members of a single sibship (aged 24 and 25 years). The fourth patient is the son (aged 4 years) of one of these brothers in the second generation. The AML was of different subtypes and a karyotypic abnormality (del[6q]) was detected in one of three patients. The first-generation patient died during chemotherapy; the remaining three patients are in complete remission after chemotherapy and autologous bone marrow transplantation.

Acute Disease↗
PubMed1998

A randomized trial of maintenance interferon following high-dose chemotherapy in multiple myeloma: long-term follow-up results.

High-dose chemotherapy (melphalan) with autologous marrow stem cell support (AMSCS) results in high response rates in multiple myeloma (MM), with up to 50% of patients achieving complete remission. However, these remissions are generally not durable. As the cytokine interferon alpha has been shown to prolong partial response following conventional chemotherapy, this trial was conducted to evaluate its role following high-dose chemotherapy. 85 patients were randomly assigned to maintenance treatment with interferon alpha, 3 x 10(6) units/m2 subcutaneously three times weekly until relapse or no further treatment following recovery from high-dose chemotherapy (melphalan 140-200 mg/m2 or busulphan 16 mg/kg) combined with AMSCS. At 5.8 years following the accrual of the last patient in this trial, 38 patients had died, 17 in the interferon arm and 21 in the control arm. The median progression-free survival (PFS) in the 42 patients randomized to interferon alpha was 46 months versus 27 months in the controls. Both overall survival and PFS, which were highly significant at median follow-up of 52 months, have now ceased to be significant, because most patients have ultimately succumbed to their disease. Interferon was tolerated by the majority of patients with very good compliance. Toxicity consisted mainly of flu-like symptoms and malaise which were usually self-limiting. The results of such a pilot study should be carefully interpreted and the benefits of interferon should be confirmed in larger multicentre studies in the setting of minimal residual disease following autologous transplantation.

Adult↗
PubMed1997

Prospective, concurrent comparison of the Cobe Spectra and Haemonetics MCS-3P cell separators for leukapheresis after high-dose filgrastim in patients with hematologic malignancies.

A prospective study was undertaken to compare the mononuclear cell, CD34+ cell, and CFU-GM yields of the Haemonetics MCS-3P and the Cobe Spectra cell separators in ten patients (nine multiple myeloma and one non-Hodgkin lymphoma) on two consecutive days after mobilization with high-dose filgrastim (12-16 micrograms/k) for 4 days. All patients were harvested once on each machine, five starting on each machine. The target duration of the procedure on the Spectra was 160 minutes, and the target blood volume processed on the MCS-3P was 60-70 ml/kg body weight. Both machines were operating on the 1995 software versions supplied by the respective manufacturers. The time taken for the procedure was significantly longer with the Haemonetics machine. The volumes of blood processed and the product collected were significantly higher with the Spectra, as were the absolute mononuclear and CD34+ cell yields, and yields per unit time. Mononuclear and CD34+ cell yields per unit volume of blood processed were comparable for both machines. The differences in CFU-GM yields were not significant, largely because of wide interpatient variations. The extent of platelet depletion as a result of the procedure was greater with the Spectra because of the higher blood volume being processed. We conclude that the Cobe Spectra is a significantly faster machine than the Haemonetics MCS-3P; and consequently, its use is associated with higher mononuclear and CD34+ cell yields.

Antigens, CD34↗