RESUMEN
Peripheral T-cell lymphoma (PTCL) encompasses a heterogeneous group of neoplasms with generally poor clinical outcome. Currently 50% of PTCL cases are not classifiable: PTCL-not otherwise specified (NOS). Gene-expression profiles on 372 PTCL cases were analyzed and robust molecular classifiers and oncogenic pathways that reflect the pathobiology of tumor cells and their microenvironment were identified for major PTCL-entities, including 114 angioimmunoblastic T-cell lymphoma (AITL), 31 anaplastic lymphoma kinase (ALK)-positive and 48 ALK-negative anaplastic large cell lymphoma, 14 adult T-cell leukemia/lymphoma and 44 extranodal NK/T-cell lymphoma that were further separated into NK-cell and gdT-cell lymphomas. Thirty-seven percent of morphologically diagnosed PTCL-NOS cases were reclassified into other specific subtypes by molecular signatures. Reexamination, immunohistochemistry, and IDH2 mutation analysis in reclassified cases supported the validity of the reclassification. Two major molecular subgroups can be identified in the remaining PTCL-NOS cases characterized by high expression of either GATA3 (33%; 40/121) or TBX21 (49%; 59/121). The GATA3 subgroup was significantly associated with poor overall survival (P = .01). High expression of cytotoxic gene-signature within the TBX21 subgroup also showed poor clinical outcome (P = .05). In AITL, high expression of several signatures associated with the tumor microenvironment was significantly associated with outcome. A combined prognostic score was predictive of survival in an independent cohort (P = .004).
Asunto(s)
Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Linfoma de Células T Periférico/clasificación , Linfoma de Células T Periférico/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Femenino , Humanos , Inmunohistoquímica , Linfoma de Células T Periférico/diagnóstico , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , Análisis de Supervivencia , Adulto JovenRESUMEN
Few large, international series of enteropathy-associated T-cell lymphoma (EATL) have been reported. We studied a cohort of 62 patients with EATL among 1153 patients with peripheral T-cell or natural killer (NK)-cell lymphoma from 22 centers worldwide. The diagnosis was made by a consensus panel of 4 expert hematopathologists using World Health Organization (WHO) criteria. Clinical correlations and survival analyses were performed. EATL comprised 5.4% of all lymphomas in the study and was most common in Europe (9.1%), followed by North America (5.8%) and Asia (1.9%). EATL type 1 was more common (66%) than type 2 (34%), and was especially frequent in Europe (79%). A clinical diagnosis of celiac sprue was made in 32.2% of the patients and was associated with both EATL type 1 and type 2. The median overall survival was only 10 months, and the median failure-free survival was only 6 months. The International Prognostic Index (IPI) was not as good a predictor of survival as the Prognostic Index for Peripheral T-Cell Lymphoma (PIT). Clinical sprue predicted for adverse survival independently of the PIT. Neither EATL subtype nor other biologic parameters accurately predicted survival. Our study confirms the poor prognosis of patients with EATL and the need for improved treatment options.
Asunto(s)
Enfermedad Celíaca/mortalidad , Enfermedad Celíaca/patología , Linfoma de Células T Asociado a Enteropatía/mortalidad , Linfoma de Células T Asociado a Enteropatía/patología , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad Celíaca/clasificación , Estudios de Cohortes , Consenso , Linfoma de Células T Asociado a Enteropatía/clasificación , Femenino , Humanos , Internacionalidad , Células Asesinas Naturales/patología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Análisis de Supervivencia , Linfocitos T/patología , Organización Mundial de la SaludRESUMEN
The International Peripheral T-cell Lymphoma Project is a collaborative effort to better understand peripheral T-cell lymphoma (PTCL). A total of 22 institutions submitted clinical and pathologic material on 1314 cases. One objective was to analyze the clinical and pathologic features of 340 cases of PTCL, not otherwise specified. The median age of the patients was 60 years, and the majority (69%) presented with advanced stage disease. Most patients (87%) presented with nodal disease, but extranodal disease was present in 62%. The 5-year overall survival was 32%, and the 5-year failure-free survival was only 20%. The majority of patients (80%) were treated with combination chemotherapy that included an anthracycline, but there was no survival advantage. The International Prognostic Index (IPI) was predictive of both overall survival and failure-free survival (P < .001). Multivariate analysis of clinical and pathologic prognostic factors, respectively, when controlling for the IPI, identified bulky disease (≥ 10 cm), thrombocytopenia (< 150 × 10(9)/L), and a high number of transformed tumor cells (> 70%) as adverse predictors of survival, but only the latter was significant in final analysis. Thus, the IPI and a single pathologic feature could be used to stratify patients with PTCL-not otherwise specified for novel and risk-adapted therapies.
Asunto(s)
Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/epidemiología , Linfoma de Células T Periférico/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Cohortes , Femenino , Humanos , Cooperación Internacional , Linfoma de Células T Periférico/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
Peripheral T-cell lymphoma (PTCL) is often challenging to diagnose and classify. Gene expression profiling was performed on 144 cases of PTCL and natural killer cell lymphoma and robust molecular classifiers were constructed for angioimmunoblastic T-cell lymphoma (AITL), anaplastic lymphoma kinase-positive (ALK(+)) anaplastic large-cell lymphoma (ALCL), and adult T-cell leukemia/lymphoma. PTCL-unclassifiable was molecularly heterogeneous, but we were able to identify a molecular subgroup with features of cytotoxic T lymphocytes and a poor survival compared with the remaining PTCL-not otherwise specified cases. Many of the pathologic features and substantial components of the molecular signature of AITL are contributed by the follicular dendritic cells, B-cell, and other stromal components. The expression of Th17-associated molecules in ALK(+) ALCL was noted and may represent aberrant activation of Th17-cell differentiation by abnormal cytokine secretion. Adult T-cell leukemia/lymphoma has a homogeneous molecular signature demonstrating high expression of human T-lymphotropic virus type 1-induced genes. These classifiers reflect the biology of the tumor cells as well as their microenvironment. We also constructed a molecular prognosticator for AITL that appears to be largely related to the microenvironmental signature, and the high expression of 2 immunosuppressive signatures are associated with poor outcome. Oncogenic pathways and tumor-host interactions also were identified, and these findings may lead to better therapies and outcome in the future.
Asunto(s)
Perfilación de la Expresión Génica , Linfadenopatía Inmunoblástica/genética , Linfoma de Células T Periférico/genética , Linfoma de Células T/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quinasa de Linfoma Anaplásico , Línea Celular , Células Cultivadas , Niño , Análisis por Conglomerados , Diagnóstico Diferencial , Femenino , Reordenamiento Génico de la Cadena gamma de los Receptores de Antígenos de los Linfocitos T/genética , Humanos , Linfadenopatía Inmunoblástica/diagnóstico , Linfadenopatía Inmunoblástica/enzimología , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Linfoma de Células T/diagnóstico , Linfoma de Células T/enzimología , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/enzimología , Masculino , Persona de Mediana Edad , Pronóstico , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Proteínas Tirosina Quinasas Receptoras , Adulto JovenRESUMEN
Transfusion therapy has greatly improved the survival of transfusion dependent thalassemia major (TM) patients; however, the resultant iron load damages tissues including the heart, liver and endocrine organs. Among these, heart complication still remains the leading cause of mortality. Myocardial iron deposition can occur independently of other solid organ involvement; conversely, the heart may be spared despite heavy siderosis in other tissues. Iron chelation treatment diminishes the risk of hemosiderosis; however, the chelation treatment has its own toxicities and might not be available to all patients due to costs. Close monitoring of individual organ iron concentration and function is thus important for optimization of individual patient care. This review outlines the importance and clinical significance of recently available MRI techniques for monitoring cardiac iron load.
Asunto(s)
Cardiopatías/etiología , Cardiopatías/patología , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/patología , Imagen por Resonancia Magnética/métodos , Talasemia beta/complicaciones , Talasemia beta/patología , Diagnóstico Diferencial , HumanosRESUMEN
Lymphopenia is a marker of inferior survival in patients with various malignancies. However, the prognostic significance of lymphopenia in peripheral T-cell lymphoma (PTCL) is unclear. We analyzed the prognostic significance of lymphopenia in 826 patients with different types of PTCL and natural killer/T-cell lymphoma (NKTCL) from the International Peripheral T-cell Lymphoma Project. Lymphopenia was defined as an absolute lymphocyte count of less than 1,000 cells per microliter. The overall frequency of lymphopenia was 35.3%, ranging from 21.1% in ALK(+) anaplastic large cell lymphoma (ALCL) to 47.5% in angioimmunoblastic T-cell lymphoma (AITL). Lymphopenia was independently associated with an inferior overall survival (OS) in patients with the lymphoma type of adult T-cell leukemia/lymphoma (ATLL), with a 2-year OS of 15% versus 40% for those without lymphopenia (P < 0.001). Lymphopenia was also an adverse predictor of survival in PTCL, not otherwise specified, but was associated with other unfavorable prognostic factors. A trend toward inferior survival for lymphopenic patients was also observed in AITL, ALK(-) ALCL and extranasal NKTCL lymphoma, whereas no difference in survival was found in nasal NKTCL, ALK(+) ALCL, or enteropathy-associated T-cell lymphoma. In this study, lymphopenia was identified as a new adverse prognostic factor in the lymphoma type of ATLL.
Asunto(s)
Linfoma Extranodal de Células NK-T/mortalidad , Linfoma de Células T Periférico/mortalidad , Linfopenia/mortalidad , Adulto , Supervivencia sin Enfermedad , Estudios de Seguimiento , Humanos , Recuento de Linfocitos , Linfoma Extranodal de Células NK-T/sangre , Linfoma Extranodal de Células NK-T/terapia , Linfoma de Células T Periférico/sangre , Linfoma de Células T Periférico/terapia , Linfopenia/sangre , Linfopenia/terapia , Masculino , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
Four patients (age 3-11 years at diagnosis) with relapsed acute promyelocytic leukemia (APL), 12-38 months from diagnosis, were treated with oral arsenic trioxide (As(2) O(3) ). One patient was treated with oral As(2) O(3) monotherapy and chemotherapy. Three patients failed initial oral or intravenous As(2) O(3) monotherapy were treated with oral As(2) O(3) plus ATRA followed by long-term oral maintenance (cumulative As(2) O(3) dose 280-2,100 mg). All patients achieved molecular remission, at a median follow up of 122 (10-132) months with no adverse effects. Oral As(2) O(3) , particularly in prolonged maintenance with oral ATRA may obviate the need of stem cell transplantation in relapsed pediatric APL.
Asunto(s)
Antineoplásicos/administración & dosificación , Arsenicales/administración & dosificación , Leucemia Promielocítica Aguda/prevención & control , Óxidos/administración & dosificación , Administración Oral , Adolescente , Trióxido de Arsénico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Leucemia Promielocítica Aguda/diagnóstico , Masculino , Recurrencia , Factores de TiempoRESUMEN
PURPOSE: To examine the reproducibility of the single breathhold T2* technique from different scanners, after installation of standard methodology in five international centers. MATERIALS AND METHODS: Up to 10 patients from each center were scanned twice locally for local interstudy reproducibility of heart and liver T2*, and then flown to a central MR facility to be rescanned on a reference scanner for intercenter reproducibility. Interobserver reproducibility for all scans was also assessed. RESULTS: Of the 49 patients scanned, the intercenter reproducibility for T2* was 5.9% for the heart and 5.8% for the liver. Local interstudy reproducibility for T2* was 7.4% for the heart and 4.6% for the liver. Interobserver reproducibility for T2* was 5.4% for the heart and 4.4% for the liver. CONCLUSION: These data indicate that T2* MR may be developed into a widespread test for tissue siderosis providing that well-defined and approved imaging and analysis techniques are used.
Asunto(s)
Sobrecarga de Hierro/patología , Hierro/metabolismo , Hígado/patología , Imagen por Resonancia Magnética/métodos , Miocardio/patología , Talasemia/sangre , Adulto , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Valores de Referencia , Reproducibilidad de los ResultadosRESUMEN
Nasal natural killer (NK)/T-cell lymphoma--classified as extranodal NK/T-cell lymphoma (ENKTL), nasal type, by the World Health Organization--is a non-Hodgkin lymphoma that is almost always associated with Epstein-Barr virus. Up to 75% of ENKTL cases occur in the upper aerodigestive tract, primarily the nasal cavity. It is the most common type of peripheral T-cell lymphoma in many Asian countries. Histologic diagnosis is essential, and staging consists of bilateral bone marrow biopsy and imaging of the neck, thorax, abdomen, and pelvis. There is a marked dichotomy in treatment and survival between localized and disseminated disease. Since disease incidence is rare even in prevalent areas, experience is limited and most treatment protocols are consensus-guided. ENKTL is both chemosensitive and radiosensitive. Early-stage, localized nasal disease is highly curable with combination therapy, but the optimal dose, combination, and sequence of radiotherapy and chemotherapy are still undefined. For patients with disseminated and extranasal disease, either at initial presentation or at relapse, the prognosis is poor. For disseminated and refractory cases, the 5-year survival rate is below 10%, and better methods of treatment are needed.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma Extranodal de Células NK-T/terapia , Neoplasias Nasales/terapia , Adulto , Terapia Combinada , Humanos , Linfoma Extranodal de Células NK-T/patología , Persona de Mediana Edad , Neoplasias Nasales/patología , Dosificación Radioterapéutica , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
A patient with a history of precursor B-cell leukemia presented with an isolated ulcerating gum lesion 8 years after allogeneic stem cell transplantation with severe graft versus host disease. A biopsy revealed an undifferentiated malignant hemic lesion. Examinations of the peripheral blood and marrow were normal. Molecular studies confirmed clonal relationship between the gum lesion with the original marrow disease, despite the anatomical, histological and chronological separations.
Asunto(s)
Neoplasias Gingivales/patología , Efecto Injerto vs Leucemia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Adulto , Neoplasias de la Médula Ósea/cirugía , Resultado Fatal , Femenino , Enfermedad Injerto contra Huésped/etiología , Hematopoyesis Extramedular , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirugía , Recurrencia , Trasplante de Células Madre/efectos adversosAsunto(s)
Regulación Neoplásica de la Expresión Génica/inmunología , Cadenas Ligeras de Inmunoglobulina/biosíntesis , Cadenas Ligeras de Inmunoglobulina/genética , Linfoma de Células B/complicaciones , Linfoma de Células B/diagnóstico , Plasmacitoma/complicaciones , Plasmacitoma/diagnóstico , Secuencia de Bases , Células Clonales/inmunología , Células Clonales/patología , Humanos , Linfoma de Células B/genética , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Plasmacitoma/genéticaAsunto(s)
Ceguera/tratamiento farmacológico , Ceguera/radioterapia , Enucleación del Ojo , Neoplasias del Ojo/tratamiento farmacológico , Neoplasias del Ojo/radioterapia , Linfoma de Células B/tratamiento farmacológico , Linfoma de Células B/radioterapia , Dolor/etiología , Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Ceguera/etiología , Neoplasias del Ojo/complicaciones , Humanos , Linfoma de Células B/complicaciones , Masculino , Persona de Mediana Edad , Dolor/diagnóstico , Manejo del Dolor/métodosRESUMEN
We describe eight cases of acute proptosis due to mantle cell lymphoma (MCL), among 26 consecutive MCL cases. The median time of onset was 29 months (range 0-102) from diagnosis. Two cases presented initially with orbital masses while five as sudden disease progression after multiple courses of chemotherapy. In each case, there was dramatic loss of vision and severe proptosis, which uniformly responded to radiotherapy and/or further chemotherapy. Unilateral blindness only occurred in two cases, with recurrent orbital relapse and repeated retinal irradiation and retro-orbital optic nerve involvement, respectively. The high incidence, as well as bilateral and recurrent nature, of orbital involvement suggested a homing mechanism of MCL to this site. Despite the absence of central nervous system involvement, most cases died of refractory disease. Apart from lymphomatous polyposis of the gut, MCL cells also show predilection to ocular presentation, and must be considered as a differential diagnosis to maltoma in the two anatomical sites.
Asunto(s)
Exoftalmia/etiología , Linfoma de Células del Manto/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Progresión de la Enfermedad , Resultado Fatal , Femenino , Humanos , Linfoma de Células del Manto/terapia , Masculino , Persona de Mediana Edad , Neoplasias Orbitales/diagnóstico , Neoplasias Orbitales/terapia , Recurrencia , Tasa de Supervivencia , Resultado del TratamientoAsunto(s)
Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Antígenos CD20/metabolismo , Linfoma de Burkitt/tratamiento farmacológico , Transformación Celular Neoplásica/patología , Trasplante de Hígado , Trastornos Linfoproliferativos/tratamiento farmacológico , Antígenos CD20/genética , Secuencia de Bases , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Transformación Celular Neoplásica/genética , Resultado Fatal , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Cadenas Ligeras de Inmunoglobulina/biosíntesis , Cadenas Ligeras de Inmunoglobulina/genética , Trasplante de Hígado/patología , Trastornos Linfoproliferativos/genética , Trastornos Linfoproliferativos/patología , Persona de Mediana Edad , Datos de Secuencia Molecular , RituximabRESUMEN
Hepatitis C virus (HCV) eradication in hemophilia patients depends on viral and patient factors. We report the treatment results with interferon 3 (5 megaunits, 3 times per week) and ribavirin (1 g daily) for 1 year in 17 Chinese patients who were negative for the human immunodeficiency virus. The HCV genotype consisted of a mixture of Western (genotypes 1, 2, and 3) and Chinese (genotypes 1 and 6) patterns. Quasi species were common (29%). Seven patients (41%) stopped treatment because of complications. Sustained HCV eradication was achieved until the end of treatment or for 24 months in 7 of 17 patients, respectively. A sustained response occurred in 50% of the patients completing treatment and occurred only in patients with genotypes 1, 3, and 6 but not with quasi species.
Asunto(s)
Antivirales/administración & dosificación , Seropositividad para VIH , VIH , Hemofilia A , Hepatitis C/tratamiento farmacológico , Interferón-alfa/administración & dosificación , Ribavirina/administración & dosificación , Adulto , Anciano , China , Femenino , Hemofilia A/complicaciones , Hemofilia A/virología , Hepatitis C/etiología , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Vogt-Kaganayi-Harada (VKH) syndrome is a rare autoimmune disease characterized by panuveitis, neuropathy and aseptic meningitis. Most patients require long-term treatment with steroids and immunosuppressants. Patients may develop concurrent autoimmune diseases, especially endocrinopathies. Secondary malignancies are rare associations. We report a Chinese man with VKH syndrome presenting with multiple cranial nerve palsy and bilateral pan-uveitis, who developed disseminated high-grade B cell lymphoma after 3-year treatment with azathioprine. This is the first report of systemic non-Hodgkin lymphoma in patients with VKH syndrome. The carcinogenic properties of azathioprine on an abnormally expanded but non-clonal lymphoid system may play a role in the pathogenesis.
Asunto(s)
Azatioprina/efectos adversos , Linfoma no Hodgkin/inducido químicamente , Síndrome Uveomeningoencefálico/complicaciones , Adulto , Carcinógenos/efectos adversos , Enfermedades de los Nervios Craneales/diagnóstico , Enfermedades de los Nervios Craneales/etiología , Humanos , Inmunofenotipificación , Ganglios Linfáticos/patología , Linfoma de Células B/inducido químicamente , Linfoma de Células B/etiología , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/etiología , Masculino , Uveítis/diagnóstico , Uveítis/etiología , Síndrome Uveomeningoencefálico/tratamiento farmacológicoRESUMEN
BACKGROUND: Graft-versus-host disease (GVHD) of the liver after allogeneic hematopoietic stem cell transplantation classically presents with increased bilirubin and alkaline phosphatase (ALP) levels. A hepatitic variant was recently recognized, with more than a 10-fold increase in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. This study defines the clinicopathologic features and prognostic implications of hepatitic GVHD compared with classic liver GVHD. METHOD: A total of 38 cases of hepatitic GVHD, 68 cases of classic liver GVHD, and 13 cases of hepatitis B virus (HBV)-related hepatitis after hematopoietic stem cell transplantation were analyzed. RESULTS: Hepatitic GVHD cases showed significantly higher ALT, AST, and ALP levels compared with classic liver GVHD cases (at onset, mean ALT: 154 vs. 58 U/L, P <0.001; AST: 167 vs. 77 U/L, P <0.001; at peak, ALT: 435 vs. 112 U/L, P <0.001; AST: 587 vs. 150 U/L, P <0.001; ALP: 416 vs. 238 U/L, P =0.001), persisted longer (74 vs. 32 days, P =0.006), and showed more lobular pathologic changes in biopsy (lobular changes: 16/26 vs. 4/19, P =0.007; hepatocyte necrosis: 16/26 vs. 6/19, P =0.008; acidophil bodies: 15/26 vs. 4/19, P =0.014) but less cholestasis (4/26 vs. 8/19, P =0.045). However, cumulative doses of immunosuppressants prescribed, response, and outcome were similar. Compared with hepatitic GVHD, HBV-related hepatitis occurred later (95 vs. 184 days, P =0.049), but clinical and biochemical profiles were similar, requiring liver biopsies for their distinction. CONCLUSIONS: Hepatitic and classic liver GVHD differed biochemically and pathologically, but these differences showed no obvious impact on outcome. The distinction of hepatitic GVHD from other hepatitis is mandatory.
Asunto(s)
Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Hepatitis/etiología , Adolescente , Adulto , Alanina Transaminasa/sangre , Fosfatasa Alcalina/sangre , Aspartato Aminotransferasas/sangre , Bilirrubina/sangre , Femenino , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Enfermedad Injerto contra Huésped/patología , Hepatitis/tratamiento farmacológico , Hepatitis/patología , Hepatitis B/tratamiento farmacológico , Hepatitis B/etiología , Hepatitis B/patología , Humanos , Hepatopatías/tratamiento farmacológico , Hepatopatías/etiología , Hepatopatías/patología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Trasplante Homólogo , Resultado del TratamientoRESUMEN
Caveolin-1 is a structural protein that may function as a scaffold for plasma membrane proteins, one of which is P-glycoprotein (P-gp), product of the multidrug resistance-1 (MDR-1) gene. We tested the hypothesis that if P-gp and caveolin-1 interacted physically, caveolin-1 and MDR-1 genes might be coordinately regulated; by quantifiying their gene expression with quantitative-polymerase chain reaction. MDR-1 and caveolin-1 gene expressions were normalized to an internal control and related to a fixed calibrator by a comparative cycle-threshold (CT) method. In four different groups of marrow samples (20 normal, 56 acute myeloid leukemias (AML) at diagnosis, 48 AMLs at relapse, and 51 regenerating marrows), caveolin-1 and MDR-1 gene expressions were positively correlated. In 65 samples with MDR-1 over-expression, caveolin-1 and MDR-1 expressions were also correlated. The coordinate expression of caveolin-1 and MDR-1 suggests that they may either interact physically, or are involved in the same aberrant pathway(s) activated during MDR-1 up-regulation.