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1.
Am J Clin Oncol ; 22(2): 107-13, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10199441

RESUMEN

The patterns of treatment for newly diagnosed breast carcinomas in older women aged 65 years or more have not been well studied, particularly in relation to screening mammography performed for the early detection of breast cancer. Therefore, the present study was performed to determine the patterns of treatment for newly diagnosed breast carcinomas in older women aged 65 years or more and to determine the impact of screening mammography on these patterns of treatment. The study population consisted of 130 women aged 65 years or more with newly diagnosed breast carcinoma from 1993 through 1994 enrolled in a large health maintenance organization. The medical records of these 130 patients were reviewed. The breast cancers detected in women who had undergone mammographic screening were more often eligible for breast-conservation treatment than the breast cancers detected in women who had not undergone mammographic screening (79% vs. 48%, respectively; p = 0.0044). For the breast cancers that were eligible for breast-conservation treatment, breast-conservation treatment was used more often for the women who had undergone mammographic screening than for the women who had not undergone mammographic screening (70% vs. 27%, respectively; p = 0.0077). Definitive radiation therapy was delivered after breast-conservation surgery in 89% (55/62) of the patients. Medical oncology consultation was obtained more commonly for more advanced staged breast cancers. Clinical management was altered in 9% (12/130) of the patients because of older patient age, comorbid medical conditions, or both. These findings have documented the patterns of treatment for older women aged 65 years or more with newly diagnosed breast cancer. Screening mammography had a significant impact on the patterns of breast cancer management, as demonstrated by the association of screening mammography with an increased eligibility for breast-conservation treatment and an increased use of breast-conservation treatment for eligible patients.


Asunto(s)
Neoplasias de la Mama/terapia , Mamografía/estadística & datos numéricos , Mastectomía/estadística & datos numéricos , Anciano , Neoplasias de la Mama/diagnóstico por imagen , Terapia Combinada , Femenino , Sistemas Prepagos de Salud , Humanos , Estados Unidos
2.
Radiology ; 205(2): 441-5, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9356626

RESUMEN

PURPOSE: To evaluate (a) the relationship between mammogram interpretation and diagnosis of new breast cancer and (b) interprovider variation in mammogram interpretation. MATERIALS AND METHODS: Interpretations of screening mammograms (133,668 mammograms in 114,899 women) acquired during 21 months in a large health maintenance organization were categorized (categories 1-5) with use of a standard format. During 1 year after mammography, new breast cancer was identified with use of claims data. Interprovider variation in the categories read was evaluated, and percentages of these categories were correlated with breast cancer detection. RESULTS: Over the 21 months, 1,018 mammograms were followed by a diagnosis of new breast cancer. The category of mammogram interpretation was strongly associated with the diagnosis of new breast cancer; in 47.5% cases of category 5 mammograms, breast cancer was diagnosed. There was substantial interprovider variation in the percentages of category 3, 4, or 5 mammograms read. The percentage of category 4 and 5 mammograms read correlated inversely with the likelihood of cancer detection (Pearson correlation coefficient [r] = -.4778 after log-log transformation, P < .001). CONCLUSION: A strong correlation existed between a mammographic abnormality suggestive of cancer and its detection; however, substantial interprovider variation in the reading of category 3, 4, and 5 mammograms and their positive predictive values existed. Reduction of interprovider variation should improve quality of care because the number of false-negative and false-positive mammograms should decrease.


Asunto(s)
Sistemas Prepagos de Salud , Mamografía , Adulto , Neoplasias de la Mama/diagnóstico por imagen , Reacciones Falso Negativas , Femenino , Humanos , Mamografía/estadística & datos numéricos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas
5.
Radiology ; 202(3): 735-8, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9051027

RESUMEN

PURPOSE: To present results with a radiology performance report to help evaluate utilization of radiologic examinations by primary-care practices (family practice, internal medicine, or pediatrics) in an independent practice association health maintenance organization (HMO). MATERIALS AND METHODS: Utilization reports for primary-care-physician practices (n = 5,000) over a 12-month period (July 1, 1993 through June 30, 1994) were derived from administrative data collected from claim and encounter forms submitted by radiologic practices. Data were divided into 22 measures to help define practice utilization. five overall measures helped evaluate procedures performed by HMO member or nonmember practices per 1,000 members. Twelve specific measures helped evaluate patterns of use of frequently ordered imaging procedures (eg, computed tomography, magnetic resonance imaging, bone scanning, cardiovascular nuclear imaging, nonobstetric ultrasound, and plain radiography). Five quality measures helped evaluate utilization of screening mammography in women aged 50-64 years (as a percentage of all women in the HMO aged 50-64 years) and of low-yield examinations (ie, sinus, rib, and skull radiography per 1,000 adult members). RESULTS: Individual practice utilisation mean results were compared with overall HMO mean results adjusted for practice type and age and sex of members. CONCLUSION: Utilization data are an integral part of evaluation of HMOs and their providers, and these results helped establish a baseline level of performance.


Asunto(s)
Diagnóstico por Imagen/estadística & datos numéricos , Sistemas Prepagos de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina , Derivación y Consulta/estadística & datos numéricos , Adulto , Capitación , Medicina Familiar y Comunitaria/estadística & datos numéricos , Femenino , Sistemas Prepagos de Salud/economía , Humanos , Medicina Interna/estadística & datos numéricos , Imagen por Resonancia Magnética/estadística & datos numéricos , Mamografía/estadística & datos numéricos , Persona de Mediana Edad , Pediatría/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud , Radiografía/estadística & datos numéricos , Escalas de Valor Relativo , Tomografía Computarizada por Rayos X/estadística & datos numéricos
7.
AJR Am J Roentgenol ; 163(1): 1-3, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8010192

RESUMEN

Our health care system, burdened by excessive costs and unprecedented growth, is in need of reform. How to carry out such reform and achieve an acceptable balance between quality and cost of care remains the dilemma. Attempts to control costs and limit growth have, in recent years, produced a disturbing trend in the quality and availability of health care benefits, focusing on benefit reduction without addressing resource utilization or quality of care. The result of these efforts? Persons who have health care insurance are paying more for basic plans and reduced benefits; others are either uninsured or underinsured. Health care benefits continue to be the fastest growing component of business expenses, strengthening the perception of diminishing competitiveness in the world market. The formation of smaller businesses offering no health care benefits continues to be problematic.


Asunto(s)
Reforma de la Atención de Salud/economía , Programas Controlados de Atención en Salud , Radiología/economía , Radiología/normas , Control de Costos , Humanos , Administración de la Práctica Médica/tendencias , Calidad de la Atención de Salud , Estados Unidos
9.
Proc Natl Acad Sci U S A ; 88(15): 6810-4, 1991 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-1650484

RESUMEN

We have studied a series of normal subjects and patients with brain tumors, by using 31P three-dimensional chemical shift imaging to obtain localized 31P spectra of the brain. A significant proportion of brain cytosolic ATP in normal brain is not complexed to Mg2+, as indicated by the chemical shift delta of the beta-P resonance of ATP. The ATP beta-P resonance position in brain thus is sensitive to changes in intracellular free Mg2+ concentration and in the proportion of ATP complexed with Mg because this shift lies on the rising portion of the delta vs. Mg2+ titration curve for ATP. We have measured the ATP beta-P shift and compared intracellular free Mg2+ concentration and fractions of free ATP for normal individuals (n = 6) and a limited series of patients with brain tumors (n = 5). In four of the five spectra obtained from brain tissue containing a substantial proportion of tumor, intracellular free Mg2+ was increased, and the fraction of free ATP was decreased, compared with normal brain.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Magnesio/metabolismo , Adenosina Trifosfato/metabolismo , Adulto , Anciano , Astrocitoma/metabolismo , Neoplasias Encefálicas/secundario , Carcinoma de Células Escamosas/metabolismo , Femenino , Glioblastoma/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Fósforo , Valores de Referencia
10.
Radiology ; 179(1): 107-10, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2006259

RESUMEN

Mobile screening mammography was offered to 3,627 employees of a large corporation in Pennsylvania and Delaware. The examination was available to women employees or employee spouses aged 35 years and older. Women were charged $30 for a standard two-view examination. They also received health education materials on mammography and breast self-examination. The remaining costs of the program were underwritten by the corporation. During this program, 3,627 mammographic studies were performed; 63 biopsies were recommended. Fifty-seven biopsies were performed, and nine cancers were diagnosed. Costs of this program are presented in detail. The authors conclude that mobile screening programs at the work site provide an inexpensive, convenient alternative to more traditional screening programs. The inherent advantages of this program are the low cost, the relative ease with which the examination can be performed, and the positive role that corporate medical personnel assume in encouraging individual and group participation.


Asunto(s)
Mamografía , Servicios de Salud del Trabajador , Adulto , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/prevención & control , Femenino , Humanos , Mamografía/economía , Persona de Mediana Edad , Unidades Móviles de Salud , Servicios de Salud del Trabajador/economía
11.
J Vasc Interv Radiol ; 2(1): 151-5, 1991 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1799745

RESUMEN

Ultrasound (US)-guided and fluoroscopically guided pericardial catheter placement was performed in 12 patients with known underlying malignancy who had clinical and radiographic evidence of a significant pericardial effusion. US guidance facilitated placement of a 22-gauge needle by means of a subxyphoid or transthoracic approach. The tract was subsequently dilated over a wire under fluoroscopic guidance with placement of either an 8.5- or 10-F catheter. This technique successfully established pericardial drainage in all patients with excellent symptomatic relief. Cytologic findings were positive for malignancy in 10 of the 12 patients. Radiologically guided pericardiocentesis allowed safe, rapid stabilization of the condition of patients with symptoms from pericardial effusion. This resulted in excellent palliation in patients with terminal disease and improvement in the clinical status of other patients so that additional therapies, such as sclerosis with tetracycline or surgical placement of a pericardial window, could be performed on an elective basis.


Asunto(s)
Drenaje/métodos , Derrame Pericárdico/terapia , Adulto , Anciano , Cateterismo/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Derrame Pericárdico/etiología , Técnicas de Ventana Pericárdica , Punciones
12.
Radiology ; 177(3): 643-9, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2243963

RESUMEN

Multivoxel magnetic resonance (MR) spectroscopy and novel data analysis techniques were developed to obtain high-quality phosphorus-31 metabolite images from the human brain and to overlay each metabolite distribution directly onto corresponding hydrogen-1 MR images. The P-31 MR spectroscopic data were acquired by means of three-dimensional chemical shift imaging (phase encoding in three spatial dimensions) on a 1.5-T clinical instrument equipped with a specially designed quadrature P-31 birdcage coil constructed in the authors' laboratory. Axial, sagittal, and coronal metabolite images based on the area for any one of five peak regions (phosphodiester; phosphocreatine; gamma, alpha, and beta adenosine triphosphate) were generated from 8 X 8 X 8 or 12 X 12 X 8 CSI arrays with voxel sizes of 27 cm3 and 12 cm3, respectively. The positions of these images were aligned with anatomic features by means of the voxel-shifting capability of the Fourier transform. Direct overlays of these metabolite images on corresponding proton images demonstrated excellent correlation with anatomy, factors indicating the utility of this technique for viewing P-31 metabolite levels in all areas of the brain simultaneously.


Asunto(s)
Encéfalo/patología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Adulto , Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Humanos , Masculino
13.
AJR Am J Roentgenol ; 153(6): 1309-11, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2479242

RESUMEN

The technique, results, and complications of 109 consecutive sonographically guided therapeutic paracenteses performed on 43 patients with malignant ascites are summarized. A 5.5-French Sacks One-Step Catheter was used in all cases but five in which tissue resistance prohibited passage of the catheter through the abdominal wall. The procedure was performed on an inpatient basis 70 times and in an outpatient setting 39 times. Colonic, ovarian, and breast carcinomas accounted for over 50% of the tumors resulting in malignant fluid collections. Three complications (hypotension, 2.6%) were directly related to the procedure; two of them were fatal (1.6%). The amount of ascitic fluid drained within the first 24 hr averaged 3.5 l at rates of 100-150 ml/sec. Ninety-five procedures (87%, in 39 patients) resulted in improvement of symptoms after drainage as manifested by decreased pain from abdominal distention, alleviation of nausea, improved appetite, or decreased dyspnea. The duration of symptomatic relief ranged from 4 days to 45 days (mean, 10.4 days). Sonographically guided paracentesis is an effective procedure that can be performed for short-term relief of symptoms caused by malignant ascites.


Asunto(s)
Ascitis/terapia , Neoplasias/complicaciones , Cuidados Paliativos , Ultrasonografía , Adulto , Anciano , Anciano de 80 o más Años , Ascitis/diagnóstico , Ascitis/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Succión/instrumentación , Succión/métodos
14.
Radiology ; 172(1): 243-6, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2740510

RESUMEN

Mammography utilization remains below the level needed to achieve the National Cancer Institute's year-2000 goals for reducing breast cancer mortality by 50%. Previous research has identified both patient and physician barriers. The authors interviewed 600 randomly selected women who were offered a free mammographic examination. Interviews were conducted by professional interviewers using a brief, structured questionnaire. Data were analyzed with chi 2 Wilcoxon and Kruskal-Wallis rank-sum statistics and discriminant analysis. Noncompliant subjects reported more barriers than compliant subjects. The former were more likely to believe that mammography is unnecessary in the absence of symptoms and that it is inconvenient. In both the bivariate and multivariate analyses, the woman's belief that her doctor believes in regular mammography was an important predictor of compliance.


Asunto(s)
Mamografía , Tamizaje Masivo , Cooperación del Paciente , Adulto , Anciano , Actitud , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/prevención & control , Neoplasias de la Mama/psicología , Femenino , Conductas Relacionadas con la Salud , Humanos , Mamografía/psicología , Mamografía/estadística & datos numéricos , Persona de Mediana Edad , Factores Socioeconómicos
15.
Int J Radiat Oncol Biol Phys ; 14(5): 831-8, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3360652

RESUMEN

Oxygen distribution was measured in 31 fixed lymph node metastases (mean diameter 4.4 cm +/- 0.8 cm) from squamous cell carcinoma of the head and neck by passing a needle electrode through each tumor under CT guidance. Thirteen tumors had uniform oxygen distribution with all measurements under 10 mm Hg. Six tumors had uniform oxygen distribution with all measurements above 10 mm Hg, and twelve tumors had variable oxygen distribution with measurements higher in the periphery than in the center. Response to radiation therapy was judged by changes in tumor volume 90 days following completion of therapy compared to pre-therapy volume. Eighteen tumors were considered complete responders (CR); eleven, non-responders (NR); two, partial responders (PR). No statistically significant difference in radiation dose or tumor size was seen in the PR and CR groups. Mean pO2 was 20.6 (+/- 4.4) mm Hg in the CR group and 4.7 (+/- 3.0) mm Hg in the NR group (p less than 0.001). Normalized pO2 content defined as the total tumor oxygen content normalized by dividing by the volume was 37.4 (+/- 8.2) mm Hg in the CR group and 8.2 (+/- 5.1) mm Hg in the NR group (p less than 0.001). The volume and oxygen levels of each tumor were tabulated and analyzed. Twelve tumors had greater than 26% of their volume containing a pO2 less than 8 mm Hg. Eleven of these were NR and one PR. Nineteen tumors had less than 26% of their volume containing a pO2 less than 8 mm Hg. Eighteen were CR and one PR (p less than 0.001). These data suggest that oxygen plays a significant role in human tumor response to radiation therapy. Oxygen measurements appear to allow separation of subgroups of patients with a poor prognosis who would most benefit from maneuvers to circumvent the hypoxic effect.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Metástasis Linfática/metabolismo , Oxígeno/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/radioterapia , Presión Parcial
17.
Radiology ; 163(1): 172-5, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3823433

RESUMEN

Photodynamic therapy was performed on ten tumors in patients who did not respond to initial therapy and for whom no additional conventional therapy was available. A sensitizing agent (hematoporphyrin derivative [HpD]) was injected directly into each tumor under computed tomographic (CT) guidance to deliver high concentrations to the tumor and to minimize systemic toxicity. Three to 6 days after the injection, a clear Teflon sheath catheter was placed into the tumor under CT guidance. The tumor was exposed to red light (630-nm wavelength) through laser fiberoptics inserted in the sheath. The initial investigation confirmed the technical feasibility of CT-guided photodynamic therapy by means of intratumoral HpD injections and laser exposure through fiberoptics inserted in sheath catheters. The toxicity from a single treatment was minor, and the tumor response was encouraging.


Asunto(s)
Fotorradiación con Hematoporfirina , Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Tomografía Computarizada por Rayos X , Cateterismo/métodos , Evaluación de Medicamentos , Tecnología de Fibra Óptica/instrumentación , Humanos
18.
Skeletal Radiol ; 10(2): 95-101, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6310795

RESUMEN

A wide spectrum of osseous abnormalities has been reported in association with vascular lesions. Enchondromas, bone hypertrophy, bone lysis, and sclerotic bone lesions have all been reported in association with hemangiomas, lymphangiomas, varicosities, and arteriovenous fistulae. These associations can be grouped into four major syndromes: Maffucci syndrome, mixed sclerosing bone dystrophy with angiodysplasia, congenital angiectatic hypertrophy (Klippel-Trenaunay-Weber syndrome), and massive osteolysis (Gorham syndrome).


Asunto(s)
Angiomatosis/diagnóstico por imagen , Malformaciones Arteriovenosas/diagnóstico por imagen , Resorción Ósea/diagnóstico por imagen , Melorreostosis/diagnóstico por imagen , Osteocondrodisplasias/diagnóstico por imagen , Osteólisis Esencial/diagnóstico por imagen , Adulto , Neoplasias Óseas/diagnóstico por imagen , Humanos , Síndrome de Klippel-Trenaunay-Weber/diagnóstico por imagen , Masculino , Radiografía , Síndrome
20.
Proc Natl Acad Sci U S A ; 77(1): 584-7, 1980 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6244567

RESUMEN

Human monocytes stimulated with phorbol myristate acetate were able to rapidly destroy autologous erythrocyte targets. Monocyte-mediated cytotoxicity was related to phorbol myristate acetate concentration and monocyte number. Purified preparations of lymphocytes were incapable of mediating erythrocyte lysis in this system. The ability of phorbol myristate acetate-stimulated monocytes to lyse erythrocyte targets was markedly impaired by catalase or superoxide dismutase but not by heat-inactivated enzymes or albumin. Despite a simultaneous requirement for superoxide anion and hydrogen peroxide in the cytotoxic event, a variety of hydroxyl radical and singlet oxygen scavengers did not effect cytolysis. However, tryptophan significantly inhibited cytotoxicity. The myeloperoxidase inhibitor cyanide enhanced erythrocyte destruction, whereas azide reduced it modestly. The inability of cyanide to reduce cytotoxicity coupled with the protective effect of superoxide dismutase suggests that cytotoxicity is independent of the classic myeloperoxidase system. We conclude that monocytes, stimulated with phorbol myristate acetate, generate superoxide anion and hydrogen peroxide, which together play an integral role in this cytotoxic mechanism.


Asunto(s)
Citotoxicidad Inmunológica , Monocitos/inmunología , Catalasa/metabolismo , Citotoxicidad Inmunológica/efectos de los fármacos , Eritrocitos/inmunología , Radicales Libres , Humanos , Neutrófilos/inmunología , Peróxidos/metabolismo , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacología
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