RESUMEN
BACKGROUND: Whole-body (18)F-deoxyglucose positron emission tomography (FDG-PET) has the potential to improve the management of non-small-cell lung cancer (NSCLC). We prospectively evaluated the impact of combining FDG-PET with conventional staging methods, including computed tomography (CT), on the staging and management of patients with potentially resectable NSCLC. METHODS: Ninety-four consecutive patients with newly diagnosed/suspected NSCLC were enrolled. Each patient was first staged by using conventional methods, and then by FDG-PET. FDG-PET results were forwarded in a sealed envelope and divulged at the weekly staff meeting on staging and treatment, only after "Decision 1", based on conventional staging, had been reached by consensus; reevaluation taking FDG-PET into account yielded "Decision 2". The validity of these latter decisions was analyzed retrospectively. RESULTS: Eighty-nine patients were eligible. Relative to standard imaging, FDG-PET led to clinical staging changes in 26 (29.2%) patients. The stage was lowered in eight cases (9%) and raised in 18 cases (20.2%). "Decision 2" differed from "Decision 1" in 19 patients, modifying the surgical procedure in four cases, indicating other investigations to confirm FDG-PET evidence of metastases in 12 cases, or modifying the medical treatment in three cases. These modifications were retrospectively justified in 9/19 cases, and consisted of 2/4 modifications of the surgical procedure (one hilar and one adrenal metastasis not confirmed histologically), 4/12 further investigations (axillary and liver biopsies, mediastinoscopy, occult colon cancer) and three indications for palliative treatment, in patients who all died within 3 months after FDG-PET. CONCLUSIONS: Based on FDG-PET, management was modified in 19/89 (21.3%) patients, but these changes were justified in only 9/89 patients (10.1%). FDG-PET can detect asymptomatic local and distant metastases and improves the preoperative assessment of NSCLC, thereby avoiding unnecessary surgery. However, histological verification is required because of the risk of false-positive results.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/cirugía , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/secundario , Neoplasias del Colon/diagnóstico por imagen , Toma de Decisiones , Reacciones Falso Positivas , Femenino , Humanos , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/diagnóstico por imagen , Escisión del Ganglio Linfático , Metástasis Linfática/diagnóstico por imagen , Masculino , Mediastinoscopía , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Primarias Desconocidas/diagnóstico por imagen , Cuidados Paliativos , Planificación de Atención al Paciente , Neumonectomía , Estudios Prospectivos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Imagen de Cuerpo EnteroRESUMEN
Acute osteomyelitis, although a rare complication in neonates, is a diagnostic and therapeutic challenge. Successful treatment to avoid functional sequelae depends on early recognition of infection and rapid initiation of therapy. Although Staphylococcus aureus is the most common causative agent, coagulase-negative Staphylococcus (CONS), well known for bloodstream infection, can be involved in neonatal osteomyelitis. Risk factors of osteomyelitis include prematurity and invasive procedures, such as long-term central venous catheterization. We report on 3 cases of acute CONS osteomyelitis in preterm infants presenting with prolonged CONS bacteremia. Bacteremia persisted despite antibiotic treatment in accordance with antibiograms and despite removal of the intravascular device. All catheter cultures were negative and osteomyelitis was not located on the limb where the central catheter had been inserted in all cases. Osteomyelitis diagnosis may be difficult in neonates because of the paucity of clinical signs. In our observations, (99m)Tc scintigraphy was the key investigation for diagnosis and detection of multiple sites of bone infection. The place of this investigation is discussed in relation to other imaging techniques. These observations suggest that in the context of persisting CONS bacteremia, a secondary bone infection should be considered. Scintigraphy is a discriminating diagnostic tool.
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Coagulasa , Osteomielitis/microbiología , Infecciones Estafilocócicas/diagnóstico , Antibacterianos/uso terapéutico , Bacteriemia/diagnóstico , Peso al Nacer , Proteína C-Reactiva/análisis , Cesárea , Preescolar , Femenino , Gentamicinas/uso terapéutico , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Masculino , Osteomielitis/tratamiento farmacológico , Preeclampsia , Embarazo , Infecciones Estafilocócicas/tratamiento farmacológico , Vancomicina/uso terapéuticoRESUMEN
We assessed the potential benefits of including systematic 18fluorodeoxyglucose positron emission tomography (FDG-PET) for detecting tumour recurrence in a prospective randomised trial. Patients (N=130) who had undergone curative therapy were randomised to undergo either conventional (Con) or FDG-PET procedures during follow-up. The two groups were matched at baseline. Recurrence was confirmed histologically. 'Intention-to-treat' analysis revealed a recurrence in 46 patients (25 in the FDG-PET group, and 21 in the Con group; P=0.50), whereas per protocol analysis revealed a recurrence in 44 out of 125 patients (23 and 21, respectively; P=0.60). In another three cases, PET revealed unexpected tumours (one gastric GIST, two primary pulmonary cancers). Three false-positive cases of FDG-PET led to no beneficial procedures (two laparoscopies and one liver MRI that were normal). We failed to identify peritoneal carcinomatosis in two of the patients undergoing FDG-PET. The overall time in detecting a recurrence from the baseline was not significantly different in the two groups. However, recurrences were detected after a shorter time (12.1 vs 15.4 months; P=0.01) in the PET group, in which recurrences were also more frequently (10 vs two patients) cured by surgery (R0). Regular FDG-PET monitoring in the follow up of colorectal cancer patients may permit the earlier detection of recurrence, and influence therapy strategies.
Asunto(s)
Neoplasias Colorrectales/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Recurrencia Local de Neoplasia/diagnóstico por imagen , Tomografía de Emisión de Positrones , Adulto , Anciano , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Iodobenzamides labelled with radioactive iodine are undergoing clinical evaluation as imaging and potential therapeutic agents in malignant melanomas. However, the uptake mechanism in melanic tissues remains controversial. Using secondary ion mass spectrometry (SIMS), we studied the microscopic distribution of N-(2 diethylaminoethyl)-4 iodobenzamide (I-BZA) in B16 murine melanoma inoculated to C57BL/6J1 Co mice as well as in normal pigmented skin. SIMS provides specific detection of iodine-127 atoms entering 127I-BZA composition. In B16 melanoma, 127I-BZA distribution was found to be heterogeneous, with focal areas of high concentration corresponding to cells rich in melanin pigments. In skin, SIMS analysis showed 127I-BZA distribution appearing as multiple small selective concentration areas within the epidermis. The number of these foci decreased from the stratum basale towards the stratum corneum. In both tissues, the intracellular location appeared specifically intracytoplasmic, with no apparent nuclear uptake. Distribution of this molecule mirrored that of melanin pigments. There was no enhancement of uptake at the membrane site. These results suggest that, in melanic tumors as well as in normal pigmented tissue, specific uptake of 127I-BZA occurs in pigment cells, with a possible link to melanin pigments.
Asunto(s)
Benzamidas/metabolismo , Melanoma/metabolismo , Trasplante de Neoplasias , Piel/metabolismo , Espectrometría de Masa de Ion Secundario , Animales , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Masculino , Melaninas/metabolismo , Melanoma/patología , Ratones , Especificidad de Órganos , Piel/citología , Piel/patología , Células Tumorales CultivadasRESUMEN
The pretargeting technique referred to as the Affinity Enhancement System (AES) uses bispecific antibodies and radiolabeled bivalent haptens that bind cooperatively to target cells in vivo. Experimental and clinical data demonstrate that DTPA bivalent haptens can deliver large radiation doses to tumor cells with high tumor to normal tissue contrast ratios and long activity residence time in tumors. Preliminary clinical results of radioimmunotherapy of medullary thyroid carcinomas and lung cancers look promising. Very encouraging results in biodistribution and radioimmunotherapy experiments in animals have been obtained with new haptens bearing two histamine-hemisuccinate suitable for 131I, 99mTc and 188Re labeling. Targeting isotopes to double antigen positive tumor cells provides a binding enhancement that increases specificity for tumor cells as compared to single antigen targeting on normal cells. This approach may be beneficial for targeting isotopes to B type acute lymphoblastic leukemia and Burkitt lymphoma, as well as others tumors co-expressing two markers of low specificity, and might increase tumor irradiation with minimal irradiation of normal cells.
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Neoplasias/diagnóstico por imagen , Radioinmunodetección , Radioinmunoterapia , Haptenos/uso terapéutico , Humanos , Neoplasias/radioterapiaRESUMEN
HYPOTHESIS: Parathyroid scanning, based on simultaneous recording of technetium Tc 99m sestamibi and iodine 123 images, is able to identify patients with multiple parathyroid gland disease and is a safe imaging technique for unilateral parathyroid surgery. DESIGN: Scintigraphic criteria of eligibility for unilateral surgery were prospectively tested against findings of conventional bilateral surgery. SETTING: Patients referred to an endocrine surgeon in a university hospital. PATIENTS: Seventy consecutive patients with primary hyperparathyroidism had dual-isotope scanning before conventional surgery. Forty-one patients had scan findings compatible with unilateral surgery, with a single focus of high intensity seen on the anterior and lateral views. The remaining 29 patients had 1 or more criteria of ineligibility: (1) scan findings pointing to multiple gland disease, (2) no well-identified focus, (3) contralateral thyroid nodule requiring surgical management, or (4) family history of hyperparathyroidism or multiple endocrine disease. MAIN OUTCOME MEASURES: Number of enlarged parathyroid glands at surgical inspection and calcemia follow-up. RESULTS: None of the 41 patients, with a single well-defined focus on the scan image, showed evidence of multiple parathyroid involvement. Each parathyroid adenoma was resected from the precise site predicted by the subtraction scan. Nine patients (13%) had surgical findings of multiple parathyroid gland disease. All 9 were ineligible based on preoperative image findings. CONCLUSIONS: Unilateral surgery can be safely offered to 60% of patients with primary hyperparathyroidism, on the basis of simultaneous (99m)Tc-sestamibi and (123)I scanning. This may reduce the length of the operation, anesthesia requirements, and hospital stay, and the risks of hypoparathyroidism and injury to the recurrent laryngeal nerve.
Asunto(s)
Hiperparatiroidismo/diagnóstico por imagen , Hiperparatiroidismo/cirugía , Radioisótopos de Yodo , Radiofármacos , Tecnecio Tc 99m Sestamibi , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , CintigrafíaRESUMEN
Patients with recurrent or metastatic medullary thyroid carcinoma (MTC) were referred for pretargeted immunoscintigraphy (Affinity Enhancement System; AES) and radioimmunoguided surgery (RIGS). Data collected from 13 patients establish that whole-body AES immunoscintigraphy revealed metastases < 360 mg and RIGS detected micrometastases (5-15 mg). All tissue samples removed by the surgeon were diagnosed by histology and immunohistochemistry of calcitonin to check the accuracy of IS and RIGS results. AES immunoscintigraphy is very sensitive. Of 34 metastases or recurrences detected, 22 had escaped physical examination or conventional imaging. The accuracy of RIGS was 86%, its sensitivity 75%, and its specificity was 90% (n = 208). IS and RIGS detected occult tumors that would have escaped surgery, clearly demonstrating clinical benefit. Serum calcitonin (normal, 10 pg/ml) and carcinoembryonic antigen (normal, 5 ng/ml) of two patients were restored to normal. In patients whose tumors were discovered, progression of their disease was slowed, as evidenced by the large decrease in serum calcitonin and carcinoembryonic antigen, an important prognostic factor. Surgery was canceled in one case where IS detected distant metastases out of surgical reach. Thus, AES immunoscintigraphy and RIGS might be of valuable help for the surgical management of medullary thyroid carcinoma.
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Carcinoma Medular/secundario , Radioinmunodetección , Neoplasias de la Tiroides/diagnóstico por imagen , Adulto , Anciano , Calcitonina/análisis , Antígeno Carcinoembrionario/sangre , Carcinoma Medular/diagnóstico por imagen , Carcinoma Medular/patología , Carcinoma Medular/cirugía , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugíaAsunto(s)
Neoplasias Gastrointestinales/química , Tumores Neuroendocrinos/química , Neoplasias Pancreáticas/química , Receptores de Somatostatina/análisis , 3-Yodobencilguanidina , Secuencia de Aminoácidos , Neoplasias Gastrointestinales/diagnóstico por imagen , Neoplasias Gastrointestinales/radioterapia , Humanos , Cuidados Intraoperatorios , Datos de Secuencia Molecular , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/radioterapia , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/radioterapia , Cintigrafía , RadiofármacosRESUMEN
Technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) labelling of white blood cells, routinely used for the detection of infection, results in the incorporation of radioactivity by polymorphonuclear leucocytes and also lymphocytes and can induce cell lesions in the latter case. The aim of this study was therefore to acquire data on the morphological and functional status of labelled lymphocytes present in the 99mTc-HMPAO leucocyte mixture and to determine the cellular consequences of labelling. The mean radioactivity associated with lymphocytes was 325 +/- 10.8 kBq/10(6) lymphocytes under standard labelling conditions. Microautoradiographic studies showed that labelling was heterogeneous (4% intensely labelled cells), which prevented calculation of the mean absorbed dose. The frequency of chromosomal aberrations (dicentrics and rings) in the labelled lymphocytes for 380 kBq/10(6) cells was 1.08 +/- 0.09 but no abnormality was observed in the unlabelled control lymphocytes. The plating efficiency of labelled lymphocytes was reduced, as compared with that for control cells, but some lymphocytes were still able to form clones and were still "alive" by radiobiological definition. It is therefore suggested that lymphocytes should be removed from 99mTc-HMPAO cell preparations before administration to patients.
Asunto(s)
Leucocitos/diagnóstico por imagen , Linfocitos/diagnóstico por imagen , Radiofármacos/efectos adversos , Exametazima de Tecnecio Tc 99m/efectos adversos , Autorradiografía , Aberraciones Cromosómicas/fisiología , Humanos , Técnicas In Vitro , Marcaje Isotópico , Linfocitos/fisiología , Linfocitos/ultraestructura , Microscopía Electrónica , Fitohemaglutininas/farmacología , Cintigrafía , Timidina/metabolismoRESUMEN
The 123I-N-(2-diethylaminoethyl)4-iodobenzamide (123I-BZA) is a new radiopharmaceutical used for the scintigraphic imaging of malignant melanomas. The mechanism for BZA uptake in melanic tissues is still unknown. Two methods of microanalysis, secondary ion mass spectrometry and electron probe X-ray microanalysis, were used to determine tissue distribution and subcellular location of unlabelled BZA in the C57BL6/J1 co mouse eye. Microanalysis showed elective BZA uptake by the pigmented structures of the eye: choroidal melanocytes and retinal pigment cells, where it was specifically located within melanosomes. The tropism of BZA for melanic tumours, as well as for normal pigmented tissues, could be explained by a high affinity for the melanin pigment.
Asunto(s)
Benzamidas/aislamiento & purificación , Compartimento Celular , Medios de Contraste/aislamiento & purificación , Ojo/ultraestructura , Animales , Benzamidas/metabolismo , Transporte Biológico , Coroides/metabolismo , Coroides/ultraestructura , Medios de Contraste/metabolismo , Microanálisis por Sonda Electrónica , Ojo/metabolismo , Masculino , Melanocitos/metabolismo , Melanocitos/ultraestructura , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica , Pigmentación , Retina/metabolismo , Retina/ultraestructura , Espectrometría de Masa de Ion Secundario , Distribución TisularRESUMEN
UNLABELLED: The radiation dose rate delivered by electron emissions of 99mTc, 123I, 111In, 67Ga and 201Tl was evaluated at the subcellular level. METHODS: Spherical models of sources were used to simulate various cellular localizations of radionuclides. These models were applied to large lymphocytes, assuming uniform distributions of radioactivity throughout the nucleus, the cytoplasm or the cell membrane surface. RESULTS: The graphs of the absorbed dose rate plotted according to the distance from the center of the cell show that the dose rate strongly depends on the subcellular distribution of the radioisotope. The absorbed dose rate D(0) at the center of the cell delivered by a constant cellular radioactivity of 99mTc, 123I, 111In, 67Ga and 201Tl is respectively 94, 21, 18, 74 and 76 times higher if the radioactivity is localized within the cell nucleus than if it is situated only on the cell membrane. D(0) for subcellular localizations was compared to D(0) obtained by assuming uniform distribution of radioactivity throughout the cell. This latter assumption may underestimate the dose rate from 2.8- to 3.2-fold if the tracer is exclusively localized within the nucleus or overestimate from 4.3- to 30-fold if the tracer is localized within the cytoplasm or on the cell membrane, depending on the radionuclide. CONCLUSION: Such findings show that the localization of radiopharmaceuticals at the subcellular level plays a crucial role in determining the actual dose delivered to the cell nucleus in diagnostic nuclear medicine procedures.
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Núcleo Celular/efectos de la radiación , Electrones , Radioisótopos , Membrana Celular/efectos de la radiación , Citoplasma/efectos de la radiación , Radioisótopos de Galio , Humanos , Radioisótopos de Yodo , Linfocitos/efectos de la radiación , Linfocitos/ultraestructura , Modelos Estructurales , Dosis de Radiación , Tecnecio , Radioisótopos de TalioRESUMEN
Owing to the lack of a reference technique and of an international cobalamin (vitamin B12) standard, and the large discrepancy between laboratory norms, the authors performed a multicentric study to compare five RIA kits usually used. First, classical tests were used to evaluate the analytical performances of each kit. Results did not demonstrate any superiority of one kit over another. Secondly, B12 values were classified among three categories (low, normal and high) characterized by laboratory and then manufacturer norms. The concordance between these two "judgments" was evaluated with the Kappa coefficient. In addition, the Kappa index proved that the norms supplied by the manufacturer were better than those of laboratories. But mean Kappa coefficient established for each norm gave us an unsatisfactory result. Third, clinical informations allowed to improve the classification of the patients. New limits were defined for each technique and should be tested further, routinely in each laboratory.
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Radioinmunoensayo/métodos , Vitamina B 12/sangre , Anemia/sangre , Humanos , Técnicas In Vitro , Hepatopatías/sangre , Reproducibilidad de los Resultados , Esplenomegalia/sangreRESUMEN
We report a case of accessory spleen, 1 cm in diameter, responsible for recurrence of an idiopathic thrombocytopenic purpura after splenectomy. This case is original in that the accessory spleen could only be detected by transoperative scintigraphy. Transoperative scintigraphy is a simple method to be used when one or several unrecognized accessory spleens are responsible for recurrence of a blood disease after excision of the principal spleen.
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Púrpura Trombocitopénica/diagnóstico por imagen , Bazo/anomalías , Enfermedades del Bazo/diagnóstico por imagen , Anciano , Femenino , Humanos , Cuidados Intraoperatorios , Púrpura Trombocitopénica/complicaciones , Púrpura Trombocitopénica/cirugía , Cintigrafía , Recurrencia , Esplenectomía , Enfermedades del Bazo/complicaciones , Enfermedades del Bazo/cirugíaAsunto(s)
Leucocitos Mononucleares , Compuestos de Organotecnecio , Oximas , Adhesión Celular , Supervivencia Celular , Quimiotaxis de Leucocito , Humanos , Marcaje Isotópico , Leucocitos Mononucleares/fisiología , Leucocitos Mononucleares/ultraestructura , Neutrófilos/fisiología , Neutrófilos/ultraestructura , Oxígeno/metabolismo , Superóxidos/metabolismo , Exametazima de Tecnecio Tc 99mRESUMEN
The technique, advantages and pitfalls of the isotopic localization and control during operation in orthopaedic surgery were evaluated throughout 28 interventions on lesions, which exhibited an increased uptake of a radioactive bone-seeker: the dimethyl-aminodiphosphonate, provisionally designated SF44 (Laboratoires Solabco, Coutras, France). For bone scanning, following the injection of this radiopharmaceutical that increased by 25% the lesion to normal bone ratio compared to the data for the diphosphonates in current use, the localization of lesions at surgical sites was carried out with the use of a sterilisable small radiation probe of a circular cross section 2 mm in diameter (Quartz et Silice, Paris, France). The probe was connected to a portable electronic device that converted the rates of radioactive disintegration into an acoustic signal, which increased with increasing radioactivity (Novelec, Meylan, France). The method was atraumatic and has proved to be useful at various times of the operation. More often, it was used to locate the lesion on the exposed bone. It enabled monitoring the progress of excisions and allowed to shorten their dimensions. The method was of great value at the end of the intervention for ensuring a complete excision as indicated by the lack of any residual focus of increased uptake detectable on the periphery of the operative site. Isotopic control during an operation is fully efficient to locate osteoid osteomas and other circumscribed lesions of the skeleton that give rise to an increased uptake of radioactivity.
Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Difosfonatos , Compuestos Organometálicos , Compuestos de Organotecnecio , Osteoma Osteoide/diagnóstico por imagen , Tecnecio , Adolescente , Adulto , Niño , Granuloma Eosinófilo/diagnóstico por imagen , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Radiometría/instrumentación , CintigrafíaRESUMEN
Little is known about mechanisms of systemic hypotension frequently reported during plasma exchange (PE). Type of substitution fluids may interfere with hemodynamic tolerance. In a prospective study, right heart catheterization was performed during 18 PE by filtration with isovolumic substitution. Blood volume was measured with 51Cr tagged erythrocytes and plasma volume (PV) calculated from hematocrit. Substitution fluids were either albumin (A; n = 9) or A + gelatin (A + G; n = 9). In both groups, PE induces significant (p less than 0.01) decreases of mean arterial pressure: group A: - 21 +/- 14%; group A + G: - 23 +/- 15%; of pulmonary wedge pressure: group A: - 41 +/- 33%; group A + G: - 36 +/- 22%; of cardiac index: group A: - 38 +/- 18%; group A + G: - 25 +/- 15%. Plasma volume also decreases after PE: group A: - 13.5 +/- 4%; group A + G: - 18.5 +/- 4%. None of the variations are significantly different between the two groups. So we think that substitution with albumin alone has no advantage for hemodynamic tolerance.
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Albúminas/administración & dosificación , Gelatina/administración & dosificación , Hemodinámica , Intercambio Plasmático , Sustitutos del Plasma/administración & dosificación , Volumen Plasmático , Humanos , Estudios ProspectivosRESUMEN
The experimental data obtained from in vivo single pass perfusion of duodenal, jejunal, and ileal intestinal segments of 33- and 50-day-old rats have been used to test a series of models for calcium absorption. Each model was checked for the statistical validity and goodness-of-fit with the experimental data. The model adopted for the duodenum and jejunum had two major components, one saturable and the other nonsaturable, and a minor secretory component. This model was not applicable to ileal calcium absorption. Here the secretory component appeared to be much more important, and the absorption parameters varied in such a manner as to suggest that this intestinal segment was capable of short term autoregulation of dietary calcium absorption.