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1.
Blood Cancer J ; 7(6): e570, 2017 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-28622303

RESUMEN

Bortezomib, in combination with dexamethasone (VD) or with the addition of cyclophosphamide (VCD), is highly effective in patients with amyloid light-chain (AL) amyloidosis. Currently, VCD is considered as a primary regimen for patients with AL, but it is not clear whether the addition of cyclophosphamide to VD further and significantly improves efficacy, given the substantial activity of bortezomib itself. We retrospectively compared the outcomes of 101 patients with AL amyloidosis who received VD (n=59) or VCD (n=42) in two consecutive periods. Early mortality after adjustment for Mayo stage was similar. On intent to treat, a hematologic response rate was 68% for patients treated with VD and 78% for VCD (P=0.26), while complete response+very good partial response (CR+VGPR) rate was 47.5% and 35%, respectively. Higher doses of dexamethasone or twice-weekly bortezomib were not associated with significantly higher CR+VGPR rates. Organ responses occurred in similar rates between the two groups. Median survival was similar (33 vs 36 months, P=0.45) even after adjustment for Mayo stage and dose and schedule of bortezomib and dexamethasone. In conclusion, bortezomib even with low doses of dexamethasone is effective for the treatment of AL amyloidosis; higher doses of dexamethasone and addition of cyclophosphamide do not seem to have a profound effect on efficacy and survival.


Asunto(s)
Amiloidosis/tratamiento farmacológico , Bortezomib/uso terapéutico , Ciclofosfamida/uso terapéutico , Dexametasona/uso terapéutico , Anciano , Amiloidosis/patología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Bortezomib/farmacología , Ciclofosfamida/farmacología , Dexametasona/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
3.
Leukemia ; 28(10): 2075-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24637336

RESUMEN

Suppression of uninvolved immunoglobulins is common in multiple myeloma (MM) but the prognostic significance of this phenomenon has not been assessed. We evaluated the prognostic significance of the preservation of uninvolved immunoglobulins in 1755 consecutive, unselected, patients with newly diagnosed, symptomatic MM with pre-therapy immunoglobulin levels measured by nephelometry. Suppression of at least one uninvolved immunoglobulin was observed in 87% of patients and was more common in patients with immunoglobulin A myeloma, those aged over 65 years, in patients with advanced-International Staging System (ISS) stage, extensive-bone marrow infiltration, anemia, low platelet counts, high levels of serum M-monoclonal protein or renal dysfunction. Patients with preserved immunoglobulins had a better survival than patients with suppressed immunoglobulins (median survival 55 vs 41.5 months, P<0.001). In multivariate analysis, preservation of uninvolved immunoglobulins was independently associated with better survival (hazard ratio: 0.781, 95% confidence interval: 0.618-0.987, P=0.039); irrespective of the treatment. In a subset of 500 patients, which were strictly followed for disease progression, preservation of uninvolved immunoglobulins was associated with a significantly longer progression-free survival (60 vs 25 months, P<0.001), independently of other common prognostic factors. In conclusion, preservation of uninvolved immunoglobulins in newly diagnosed patients with symptomatic MM was independently associated with long term disease control and improved survival.


Asunto(s)
Inmunoglobulinas/sangre , Inmunoglobulinas/inmunología , Mieloma Múltiple/inmunología , Mieloma Múltiple/terapia , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia Celular , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
6.
Am J Hematol ; 81(8): 590-7, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16823830

RESUMEN

BACKGROUND: The histopathologic features characterizing the involvement of the bone marrow (BM) in systemic lupus erythematosus (SLE) have not been systematically analyzed to date. OBJECTIVES: The aim of this study was to assess morphologic and immunohistochemical characteristics of BM involvement in SLE. PATIENTS AND METHODS: Clinical and serological data of 40 SLE patients with unexplained cytopenias were studied. Ten patients with myelodysplasia of refractory anemia (RA) were used as controls. BM aspiration, BM biopsy (BMB), and immunohistochemistry were carried out in patients and controls. BM fibrosis, BM necrosis, stromal edema, and abnormal localization of immature precursors (ALIP) were assessed according to standard criteria. RESULTS: Dyserythropoiesis and megakaryocytic atypias were uniform findings in SLE patients. The disruption of the normal BM architecture was a predominant SLE BM feature affecting cells of all three hemopoietic lineages, with both erythroid and megakaryocytic precursors tending to assume paratrabecular locations and ALIP aggregates being present in 27 cases. In addition, BM was hypocellular in 23 cases. BM necrotic alterations were evident in 90% of the cases. The density of reticulin content was generally increased. Vascular changes including dilatation of sinuses were manifest and were associated with the presence of necrotic alterations (P = 0.008). Hemoglobin levels correlated inversely with the presence of ALIP (P = 0.016). Upon comparing BMB features between SLE and RA controls there were striking similarities. CONCLUSIONS: BMB in patients with SLE and unexplained cytopenias presents a variety of histopathologic findings including BM necrosis, stromal alterations, hypocellularity, dyspoiesis, and distortion of normal BM architecture, characterized primarily by the presence of ALIP aggregates.


Asunto(s)
Médula Ósea/patología , Lupus Eritematoso Sistémico/complicaciones , Pancitopenia/complicaciones , Adolescente , Adulto , Anciano , Femenino , Humanos , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Persona de Mediana Edad , Pancitopenia/sangre , Pancitopenia/diagnóstico , Estudios Prospectivos
7.
Clin Exp Immunol ; 145(1): 71-80, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16792676

RESUMEN

Immunologically mediated thrombocytopenia is a frequent clinical manifestation in patients with systemic lupus erythematosus (SLE). Autoantibodies targeting platelet membrane glucoproteins have a central role in peripheral platelet destruction. Autoantibodies against thrombopoietin are also present in about one-third of patients, but their pathogenetic role is obscure. Thirty-eight serum samples from SLE patients were tested for anti-platelet antibodies, anti-thrombopoietin antibodies and levels of circulating thrombopoietin. Bone marrow histology was also assessed. Thirty-nine per cent of sera displayed anti-thrombopoietin antibodies and 29% had circulating anti-platelet antibodies. Anti-thrombopoietin antibodies were associated with lower thrombopoietin concentrations, and lower mean platelet values in long-term follow-up. Anti-platelet antibodies were present in about 40% of thrombocytopenic and non-thrombocytopenic individuals but were absent in patients who had recovered from thrombocytopenia, supporting their pathogenetic role. Both autoantibodies were absent in control sera from patients with rheumatoid arthritis and primary Sjögren's syndrome. Decreased bone marrow cellularity, normal or low number of hypolobulated, pyknotic megakaryocytes and stromal alterations were prominent findings in thrombocytopenic SLE patients, suggesting a defect in megakaryopoiesis. These findings were not evident in specimens from patients with idiopathic thrombocytopenic purpura who had increased megakaryocytes, normal cellularity and absence of stromal alterations. In conclusion, peripheral destruction due to platelet autoantibodies, anti-thrombopoetin antibodies, lower effective circulating thrombopoetin and impaired compensatory response due to bone marrow damage interact in SLE and thrombocytopenia ensues.


Asunto(s)
Autoanticuerpos/sangre , Lupus Eritematoso Sistémico/inmunología , Trombocitopenia/inmunología , Trombopoyetina/inmunología , Adulto , Artritis Reumatoide/inmunología , Células de la Médula Ósea/patología , Estudios de Casos y Controles , Recuento de Células , Distribución de Chi-Cuadrado , Femenino , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/patología , Masculino , Megacariocitos/patología , Persona de Mediana Edad , Recuento de Plaquetas , Glicoproteínas de Membrana Plaquetaria/inmunología , Síndrome de Sjögren/inmunología , Trombocitopenia/complicaciones , Trombocitopenia/patología , Trombopoyetina/sangre
8.
Rheumatology (Oxford) ; 45(10): 1261-5, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16567353

RESUMEN

OBJECTIVE: To assess the role of thrombocytopaenia as an independent predictor of outcome in patients with systemic lupus erythematosus (SLE). METHODS: This was a single-centre, retrospective, matched case-control study (1:2). Fifty consecutive Greek SLE patients were selected at random who had developed thrombocytopaenia during the disease course (cases) were compared with 100 SLE patients with no history of thrombocytopaenia, and matched for age, sex and disease duration (controls). Overall damage was assessed at the end of follow-up, using Systemic Lupus International Collaborating Clinics index. Total number of irreversible organ-damage events for both groups were recorded. Rates for specific outcomes and incidence-rate ratios (IRRs) for damage were estimated. Multivariate analysis estimating influential clinical and immunological factors for outcome, including thrombocytopaenia, was performed. RESULTS: After 583 person-years of follow-up for cases and 1155 for controls, we found that thrombocytopaenic individuals have a higher risk for damage (IRR 1.96, 1.52-2.53) compared with their matched controls and this effect persists throughout the course of their disease. They also have a predilection to certain types of damage involving heart and kidneys. Among other significant factors associated with damage in multivariate analysis (disease activity, serositis, anti-cardiolipin antibodies, central nervous system involvement), thrombocytopaenia appears as the most influential. CONCLUSION: Thrombocytopaenia is a quantitive and qualitative marker of impending damage in SLE patients.


Asunto(s)
Lupus Eritematoso Sistémico/sangre , Trombocitopenia/inmunología , Adolescente , Adulto , Anticuerpos Anticardiolipina/inmunología , Autoanticuerpos/inmunología , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Lupus Eritematoso Sistémico/inmunología , Masculino , Análisis Multivariante , Pronóstico , Estudios Retrospectivos
9.
Ann Rheum Dis ; 65(8): 1033-7, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16322082

RESUMEN

BACKGROUND: Primary Sjögren's syndrome (SS) is associated with an increased frequency of non-Hodgkin's lymphomas (NHLs), mainly of low histological grade. However, aggressive diffuse large B cell lymphomas (DLBCL) characterised by poor treatment outcome can also be encountered in SS. It has recently been shown that rituxan has significant therapeutic activity in this type of lymphoma. OBJECTIVE: To evaluate the efficacy of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, prednisone) in combination with rituxan in SS patients with DLBCL, and to determine the outcome in such patients. METHODS: In an open, single case trial, six SS patients with DLBCL were assigned to receive eight cycles of CHOP every three weeks plus rituxan given on day 1 of each cycle. In a retrospective study, conducted by the European Concerted Action for SS, nine cases were diagnosed as DLBCL, all of whom had been treated with CHOP alone. These patients were used as historical controls. RESULTS: The difference in the overall survival between the two treatment groups was significant. The group treated with rituxan plus CHOP had a 100% two year overall survival rate, while the historical controls had only a 37% survival rate. Extraglandular manifestations serving as predictors for lymphoma development such as palpable purpura and peripheral neuropathy disappeared. The remission of these signs was accompanied by a decrease in both circulating monoclonal cryoglobulins and rheumatoid factor activity and an increase in C4 levels. Clinically relevant toxicity was not detected. CONCLUSIONS: The addition of rituxan to standard CHOP chemotherapy results in improved treatment outcome in SS patients with aggressive DLBCL, without increasing toxicity.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfocitos B/inmunología , Depleción Linfocítica , Linfoma de Células B/terapia , Síndrome de Sjögren/terapia , Adulto , Anciano , Anticuerpos Monoclonales de Origen Murino , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Factores Inmunológicos/uso terapéutico , Linfoma de Células B/complicaciones , Linfoma de Células B/inmunología , Persona de Mediana Edad , Prednisona/administración & dosificación , Inducción de Remisión , Rituximab , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/inmunología , Tasa de Supervivencia , Factores de Tiempo , Vincristina/administración & dosificación
10.
Ann Rheum Dis ; 65(2): 144-8, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16079164

RESUMEN

Haematological abnormalities are common in systemic lupus erythematosus. Anaemia is found in about 50% of patients, with anaemia of chronic disease being the most common form. Impaired erythropoietin response and presence of antibodies against erythropoietin may contribute to the pathogenesis of this type of anaemia. Patients with autoimmune haemolytic anaemia usually belong to a distinct category, which is associated with anticardiolipin antibodies, thrombosis, thrombocytopenia, and renal disease, often in the context of secondary antiphospholipid syndrome. Autoantibodies, T lymphocytes, and deregulation of the cytokine network can affect bone marrow erythropoiesis, leading to anaemia.


Asunto(s)
Anemia Hemolítica Autoinmune/etiología , Lupus Eritematoso Sistémico/inmunología , Anemia Hemolítica Autoinmune/tratamiento farmacológico , Anemia Hemolítica Autoinmune/inmunología , Autoanticuerpos/inmunología , Eritropoyetina/inmunología , Eritropoyetina/uso terapéutico , Hematopoyesis , Humanos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Proteínas Recombinantes , Linfocitos T/inmunología
11.
Ann Rheum Dis ; 64(9): 1366-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16100344

RESUMEN

OBJECTIVES: To clarify clinical manifestations, association with disease activity, and prognostic impact of thrombocytopenia using simple and reliable indices. METHODS: 632 patients were reviewed retrospectively. Fifty patients with thrombocytopenia were included as cases and matched with 100 control patients. Clinical manifestations at first thrombocytopenic episode were recorded. Classification criteria at diagnosis, basic immunological profiles, disease activity (ECLAM), and end organ damage (SLICC) were recorded. RESULTS: 29/50 (58%) had thrombocytopenia at diagnosis of lupus. Haemorrhagic manifestations were associated with the degree of thrombocytopenia (p<0.001). Anticardiolipin antibodies were not related to the degree of thrombocytopenia or the severity of haemorrhagic manifestations. Megakaryocytes were normal or increased in 26/28 (93%) bone marrow specimens, indicating peripheral platelet destruction. Patients with high disease activity were more thrombocytopenic than controls (OR = 2.61, 95% CI 1.13 to 5.96, p = 0.009). Patients with low C3 or CH50 were more likely to be thrombocytopenic (OR = 2.36, 95% CI 1.05 to 5.26, p = 0.029). Median SLICC for lupus patients with thrombocytopenia was 2 (range 0-11) compared with 1 (range 0-12) for controls (p<0.001). No deaths occurred during thrombocytopenic episodes. CONCLUSIONS: Thrombocytopenia is not directly associated with end organ damage and mortality, but defines a subgroup of patients with higher morbidity and is thus a major complication of systemic lupus erythematosus, affecting overall prognosis.


Asunto(s)
Lupus Eritematoso Sistémico/complicaciones , Trombocitopenia/etiología , Adulto , Estudios de Casos y Controles , Femenino , Hemorragia/etiología , Humanos , Lupus Eritematoso Sistémico/sangre , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Pronóstico , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Trombocitopenia/terapia
12.
Med Phys ; 32(12): 3832-42, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16475783

RESUMEN

For the purpose of evaluating the use of 169Yb for prostate High Dose Rate brachytherapy (HDR), a hypothetical 169Yb source is assumed with the exact same design of the new microSelectron source replacing the 192Ir active core by pure 169Yb metal. Monte Carlo simulation is employed for the full dosimetric characterization of both sources and results are compared following the AAPM TG-43 dosimetric formalism. Monte Carlo calculated dosimetry results are incorporated in a commercially available treatment planning system (SWIFT), which features an inverse treatment planning option based on a multiobjective dose optimization engine. The quality of prostate HDR brachytherapy using the real 192Ir and hypothetical 169Yb source is compared in a comprehensive analysis of different prostate implants in terms of the multiobjective dose optimization solutions as well as treatment quality indices such as Dose Volume Histograms (DVH) and the Conformal Index (COIN). Given that scattering overcompensates for absorption in intermediate photon energies and distances in the range of interest to prostate HDR brachytherapy, 169Yb proves at least equivalent to 192Ir irrespective of prostate volume. This has to be evaluated in view of the shielding requirements for the 169Yb energies that are minimal relative to that for 192Ir.


Asunto(s)
Braquiterapia/métodos , Radioisótopos de Iridio/uso terapéutico , Neoplasias de la Próstata/radioterapia , Radioisótopos/uso terapéutico , Iterbio/uso terapéutico , Fenómenos Biofísicos , Biofisica , Braquiterapia/estadística & datos numéricos , Simulación por Computador , Humanos , Masculino , Método de Montecarlo , Neoplasias de la Próstata/patología , Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos
13.
Eur J Clin Invest ; 34(10): 690-700, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15473894

RESUMEN

Myelodysplastic syndrome (MDS), an acquired clonal disorder of haemopoietic progenitor cells, is characterized by haemopoietic insufficiency associated with cytopenias, leading to serious morbidity plus the additional risk of leukaemic transformation. In MDS an acquired insult to the haemopoietic stem cell leads to impaired differentiation and myelodysplasia. However, there is increasing evidence that the marrow failure of MDS is immune-mediated. A model of MDS pathophysiology suggests that transformation of normal stem cells induces an autoimmune T-cell response with the bone marrow as the target organ. This autoimmune attack results in chronic overproduction of pro-apoptotic cytokines, especially tumour necrosis factor alpha (TNFalpha). In addition, several reports have revealed that approximately 10% of MDS patients have clinical autoimmune disorders. This review illustrates the cellular/molecular mechanisms and the implication of the tumour suppressor gene interferon regulatory factor-1 (IRF-1) in the pathophysiology of MDS-associated autoimmune deregulation.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Autoinmunidad/inmunología , Síndromes Mielodisplásicos/inmunología , Apoptosis/inmunología , Proteínas de Unión al ADN/inmunología , Exones , Hematopoyesis/inmunología , Humanos , Factor 1 Regulador del Interferón , Fosfoproteínas/inmunología , Pronóstico , ARN Mensajero/inmunología
14.
Rheumatology (Oxford) ; 43(8): 1050-3, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15187246

RESUMEN

OBJECTIVE: To determine the safety and therapeutic response of a regimen consisting of cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP) plus rituximab in patients with Sjögren's syndrome (SS) and aggressive non-Hodgkin's lymphoma (NHL). METHODS: Four SS patients with aggressive marginal zone NHL were enrolled in this trial. All patients were classified according to the newly proposed revised European-American classification of lymphoid neoplasms. Three out of four patients also had mixed cryoglobulinaemia (MC) of type II. They were treated every 3 weeks for eight cycles of CHOP. Patients also received rituximab, at a dose of 375 mg per square metre, on day 1 of each of the eight cycles of CHOP. Four weeks after completion of the eighth course of CHOP plus rituximab and every 6 months thereafter, patients were re-evaluated for response. RESULTS: Complete remission of lymphoma was achieved in all four patients. The lymphoma patients remained in remission for a period of 23, 15, 12 and 10 months respectively, while certain signs and symptoms of MC type II (purpura, peripheral neuropathy and arthralgias) significantly improved with treatment. In addition, the titres of circulating cryoglobulins and RF decreased, while C4 levels returned to normal. CONCLUSION: CHOP plus rituximab was well tolerated and proved effective in SS patients with aggressive NHL. Our observations may warrant a larger controlled trial to assess the effectiveness of this regimen in such patients.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Linfoma de Células B/tratamiento farmacológico , Prednisona/uso terapéutico , Síndrome de Sjögren/complicaciones , Vincristina/uso terapéutico , Adulto , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales de Origen Murino , Antígenos CD/análisis , Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Linfocitos B/inmunología , Crioglobulinemia/etiología , Ciclofosfamida/efectos adversos , Doxorrubicina/efectos adversos , Quimioterapia Combinada , Humanos , Linfoma de Células B/etiología , Persona de Mediana Edad , Prednisona/efectos adversos , Rituximab , Resultado del Tratamiento , Vincristina/efectos adversos
15.
Ann Rheum Dis ; 63(5): 578-82, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15082491

RESUMEN

BACKGROUND: Patients with myelodysplasia may have autoimmune manifestations (AIM). Interferon regulatory factor-1 (IRF-1) is a transcription factor involved in interferon signalling, leukaemogenesis, and the development of the immune system. OBJECTIVES: To determine whether IRF-1 is implicated in the pathophysiology of AIM in myelodysplasia. METHODS: 14 patients with myelodysplasia were studied, seven with AIM and seven without. Five patients with vasculitis and seven normal subjects served as controls. The expression of IRF-1 was studied in bone marrow mononuclear cells taken from patients and controls, using a relative quantitative reverse transcriptase polymerase chain reaction. RESULTS: A 10-fold reduction in full length IRF-1 mRNA was detected in the myelodysplasia patients without AIM compared with the normal controls. In contrast, the group with AIM had increased IRF-1 transcripts, to a level almost equal to that observed in patients with vasculitis and normal controls. CONCLUSIONS: Myelodysplasia patients without IRF-1 expression had a decreased incidence of AIM. Thus the absence of IRF-1 transcription factor appears to protect against the development of autoimmunity in myelodysplasia.


Asunto(s)
Enfermedades Autoinmunes/etiología , Proteínas de Unión al ADN/inmunología , Síndromes Mielodisplásicos/inmunología , Fosfoproteínas/inmunología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Factor 1 Regulador del Interferón , Masculino , Persona de Mediana Edad , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factores de Riesgo
16.
Rheumatology (Oxford) ; 43(5): 626-32, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-14983106

RESUMEN

OBJECTIVE: To determine the clinical aspects and evolution of autoimmune inflammatory manifestations (AIMs) in patients with myelodysplastic syndrome (MDS) and ascertain the prognostic implications of these manifestations in MDS. METHODS: Seventy patients diagnosed for MDS were enrolled in a prospective cohort study of 4-yr duration. Thirteen patients with AIMs were identified (group A). The remaining 57 MDS patients without AIMs constituted the control group (group B). Demographic, clinical features, laboratory data, treatment and outcome of all these cases were recorded. RESULTS: On comparing features between the two groups we were unable to identify any particular difference (P > or = 0.05) concerning bone marrow blast count [odds ratio (OR) = 0.68], international prognostic scoring system (IPSS) (OR = 1.36), favourable cytogenetic abnormalities (OR = 0.52), leukaemic transformation (OR = 1.30) and survival (P = 0.76). Furthermore there was a significant difference in survival between low vs non-low IPSS patients for both groups (P<0.01). CONCLUSION: In a 4-yr prospective study the prognosis of MDS patients with AIMs appeared to be closely related to the IPSS subcategory of the underlying haematological malignancy and not to the autoimmune process.


Asunto(s)
Enfermedades Autoinmunes/diagnóstico , Síndromes Mielodisplásicos/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades Autoinmunes/tratamiento farmacológico , Métodos Epidemiológicos , Femenino , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/inmunología , Pronóstico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Vasculitis
17.
Phys Med Biol ; 48(5): 599-617, 2003 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-12696798

RESUMEN

We consider the problem of the global convergence of gradient-based optimization algorithms for interstitial high-dose-rate (HDR) brachytherapy dose optimization using variance-based objectives. Possible local minima could lead to only sub-optimal solutions. We perform a configuration space analysis using a representative set of the entire non-dominated solution space. A set of three prostate implants is used in this study. We compare the results obtained by conjugate gradient algorithms, two variable metric algorithms and fast-simulated annealing. For the variable metric algorithm BFGS from numerical recipes, large fluctuations are observed. The limited memory L-BFGS algorithm and the conjugate gradient algorithm FRPR are globally convergent. Local minima or degenerate states are not observed. We study the possibility of obtaining a representative set of non-dominated solutions using optimal solution rearrangement and a warm start mechanism. For the surface and volume dose variance and their derivatives, a method is proposed which significantly reduces the number of required operations. The optimization time, ignoring a preprocessing step, is independent of the number of sampling points in the planning target volume. Multiobjective dose optimization in HDR brachytherapy using L-BFGS and a new modified computation method for the objectives and derivatives has been accelerated, depending on the number of sampling points, by a factor in the range 10-100.


Asunto(s)
Algoritmos , Braquiterapia/métodos , Neoplasias de la Próstata/radioterapia , Radiometría/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Humanos , Masculino , Control de Calidad , Dosificación Radioterapéutica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Med Phys ; 29(3): 424-32, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11929024

RESUMEN

A stratified sampling method for the efficient repeated computation of dose-volume histograms (DVHs) in brachytherapy is presented as used for anatomy based brachytherapy optimization methods. The aim of the method is to reduce the number of sampling points required for the calculation of DVHs for the body and the PTV. From the DVHs are derived the quantities such as Conformity Index COIN and COIN integrals. This is achieved by using partial uniform distributed sampling points with a density in each region obtained from a survey of the gradients or the variance of the dose distribution in these regions. The shape of the sampling regions is adapted to the patient anatomy and the shape and size of the implant. For the application of this method a single preprocessing step is necessary which requires only a few seconds. Ten clinical implants were used to study the appropriate number of sampling points, given a required accuracy for quantities such as cumulative DVHs, COIN indices and COIN integrals. We found that DVHs of very large tissue volumes surrounding the PTV, and also COIN distributions, can be obtained using a factor of 5-10 times smaller the number of sampling points in comparison with uniform distributed points.


Asunto(s)
Braquiterapia/métodos , Radiometría/métodos , Humanos , Modelos Estadísticos , Programas Informáticos
19.
IEEE Trans Biomed Eng ; 48(3): 372-83, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11327506

RESUMEN

This paper describes innovative software for automatic reconstruction, which we term autoreconstruction, of plastic and metallic brachytherapy catheters using computed tomography (CT) data. No such automatic facility has previously existed in any treatment planning software. The patient data consists of a set of post-implantation CT images with the catheters in situ in their final positions. This new software solves those difficulties which arise when the catheters are intersecting or when loop techniques are used. With the software algorithms, catheter reconstruction time is significantly reduced and accuracy is also improved when compared with that achieved using the classical manual method of CT-slice-by-CT-slice reconstruction.


Asunto(s)
Algoritmos , Braquiterapia/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Planificación de la Radioterapia Asistida por Computador , Programas Informáticos , Tomografía Computarizada por Rayos X/métodos , Cateterismo , Humanos , Diseño de Software , Validación de Programas de Computación , Interfaz Usuario-Computador
20.
Med Phys ; 27(11): 2517-20, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11128303

RESUMEN

The most accurate classical dose optimization algorithms in HDR brachytherapy strongly depend on an appropriate selection of source dwell positions which fulfill user-defined geometrical boundary conditions which are relative to patient anatomy. Most anatomical situations, such as for prostate and head and neck tumors, are complex and can require geometries with 5-15 catheters with 48 possible dwell positions per catheter depending on the tumor volume. The manual selection of dwell positions using visual checks by trial and error is very time consuming. This can only be improved by the use of a technique which automatically recognizes and selects the optimum dwell positions for each catheter. We have developed an algorithm, termed an autoactivation algorithm, which improves implant planning by providing a facility for the necessary automatic recognition of HDR source dwell positions.


Asunto(s)
Braquiterapia/instrumentación , Braquiterapia/métodos , Planificación de la Radioterapia Asistida por Computador , Algoritmos , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Tomografía Computarizada por Rayos X
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