RESUMEN
RATIONALE: Lupus panniculitis (LP) is a unique variant of cutaneous lupus erythematosus. Clinical manifestations are typically mild and include erythema, nodules, and small ulcers. In certain cases, diagnosing LP may be challenging. Skin overlying the typical subcutaneous inflammation may appear normal, and bacterial superinfections of the skin sometimes mask the underlying LP. It has been suggested that a computed tomography (CT) scan may help to identify obscure LP lesions. Here, we report a case of a 54-year-old woman with an unusually severe form of LP, in which the full disease extent was only revealed by a fluorodeoxyglucose positron emission tomography (FDG-PET)/CT scan. PATIENT CONCERNS/DIAGNOSES/INTERVENTIONS/OUTCOMES: Our patient initially presented with a bacterial infection of the skin. After initial improvement with antibiotic treatment, new erythematous lesions and sterile subcutaneous pus collections developed. An FDG-PET/CT scan revealed extensive subcutaneous inflammation at sites that had appeared normal during physical examination and on CT scan. As the subcutaneous lesions showed a remarkably linear pattern on FDG-PET/CT scan, the patient was suspected of having LP. After confirmation of this diagnosis by a deep-skin biopsy, our patient was treated with systemic glucocorticoids. Eventually, our patient succumbed to complications of LP and its treatment. LESSONS: Our case demonstrates that clinical manifestations of LP are not always mild and that timely diagnosis is needed. Furthermore, we show that obscure LP lesions are more readily identified on an FDG-PET/CT scan than CT scan.
Asunto(s)
Paniculitis de Lupus Eritematoso/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Diabetes Mellitus Tipo 2/complicaciones , Diagnóstico Diferencial , Resultado Fatal , Femenino , Humanos , Persona de Mediana EdadRESUMEN
BACKGROUND: Patients with von Hippel-Lindau (VHL) disease are prone to develop pancreatic neuroendocrine tumors (pNETs). However, the best imaging technique for early detection of pNETs in VHL is currently unknown. In a head-to-head comparison, we evaluated endoscopic ultrasound (EUS) and (11)C-5-hydroxytryptophan positron emission tomography ((11)C-5-HTP PET) compared with conventional screening techniques for early detection of pancreatic solid lesions in VHL patients. METHODS: We conducted a cross-sectional, prospective study in 22 patients at a tertiary care university medical center. Patients with VHL mutation or with one VHL manifestation and a mutation carrier as first-degree family member, with recent screening by abdominal computed tomography (CT) or magnetic resonance imaging (MRI) and somatostatin receptor scintigraphy (SRS), were eligible. Patients underwent EUS by linear Pentax echoendoscope and Hitachi EUB-525, and (11)C-5-HTP PET. Patient-based and lesion-based positivity for pancreatic solid lesions were calculated for all imaging techniques with a composite reference standard. RESULTS: In 10 of the 22 patients, 20 pancreatic solid lesions were detected: 17 with EUS (P < 0.05 vs CT/MRI+ SRS), 3 with (11)C-5-HTP PET, 3 with SRS, 9 with CT/MRI, and 9 with CT/MRI + SRS. EUS evaluations showed solid lesions with a median size of 9.7 mm (range 2.9-55 mm) and most of them were homogeneous, hypoechoic, isoelastic, and hypervascular. Moreover, EUS detected multiple pancreatic cysts in 18 patients with a median of 4 cysts (range 1-30). CONCLUSIONS: EUS is superior to CT/MRI + SRS for detecting pancreatic solid lesions in VHL disease.(11)C-5-HTP PET has no value as a screening method in this setting. EUS performs well in early detection of pNETs, but its role in VHL surveillance is unclear.
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Endosonografía/métodos , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/etiología , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/etiología , Enfermedad de von Hippel-Lindau/complicaciones , Adulto , Estudios Transversales , Endosonografía/normas , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Cintigrafía , Tomografía por Rayos X , Adulto JovenRESUMEN
BACKGROUND: In multiple endocrine neoplasia type 1 (MEN1), pancreatic neuroendocrine tumors (pNETs) are the leading MEN1-related cause of death. OBJECTIVE: To evaluate EUS and (11)C-5-hydroxytryptophan positron emission tomography ((11)C-5-HTP PET), compared with the recommended screening techniques in MEN1 patients for early detection of pNETs. DESIGN: Cross-sectional study. SETTING: Tertiary-care university medical center. PATIENTS: This study involved 41 patients with a proven MEN1 mutation or with one MEN1 manifestation and a mutation carrier as a first-degree family member, with recent screening by abdominal CT or magnetic resonance imaging (MRI) and somatostatin receptor scintigraphy (SRS). INTERVENTIONS: EUS by using a linear Pentax echoendoscope and Hitachi EUB-525 and (11)C-5-HTP PET. MAIN OUTCOME MEASUREMENTS: Patient-based and lesion-based positivity for pNET was calculated for all imaging techniques. The McNemar test was used to compare the yield of the 4 imaging techniques. RESULTS: In 35 of 41 patients, 107 pancreatic lesions were detected in total. EUS detected 101 pancreatic lesions in 34 patients, (11)C-5-HTP PET detected 35 lesions in 19 patients, and CT/MRI + SRS detected 32 lesions in 18 patients (P < .001). (11)C-5-HTP PET performed similarly to CT/MRI + SRS and better compared with SRS only (13 lesions in 12 patients), both at a patient-based and lesion-based level (P < .05). LIMITATIONS: Single-center study. CONCLUSION: EUS is superior to CT/MRI + SRS for pancreatic lesion detection in patients with MEN1. In this setting, (11)C-5-HTP PET is not useful. We recommend EUS as the first-choice pancreas imaging technique in patients with MEN1. ( CLINICAL TRIAL REGISTRATION NUMBER: NTR1668.).
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Neoplasia Endocrina Múltiple Tipo 1/diagnóstico , Tumores Neuroendocrinos/diagnóstico , Páncreas/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico , 5-Hidroxitriptófano , Adolescente , Adulto , Anciano , Radioisótopos de Carbono , Estudios Transversales , Detección Precoz del Cáncer , Endosonografía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple Tipo 1/complicaciones , Tumores Neuroendocrinos/etiología , Neoplasias Pancreáticas/etiología , Tomografía de Emisión de Positrones , Estudios Prospectivos , Radiofármacos , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X , Adulto JovenRESUMEN
Neuroendocrine tumors can originate almost everywhere in the body and consist of a great variety of subtypes. This paper focuses on molecular imaging methods using nuclear medicine techniques in neuroendocrine tumors, coupling molecular uptake mechanisms of radiotracers with clinical results. A non-systematic review is presented on receptor based and metabolic imaging methods. Receptor-based imaging covers the molecular backgrounds of somatostatin, vaso-intestinal peptide (VIP), bombesin and cholecystokinin (CCK) receptors and their link with nuclear imaging. Imaging methods based on specific metabolic properties include meta-iodo-benzylguanide (MIBG) and dimercapto-sulphuric acid (DMSA-V) scintigraphy as well as more modern positron emission tomography (PET)-based methods using radio-labeled analogues of amino acids, glucose, dihydroxyphenylalanine (DOPA), dopamine and tryptophan. Diagnostic sensitivities are presented for each imaging method and for each neuroendocrine tumor subtype. Finally, a Forest plot analysis of diagnostic performance is presented for each tumor type in order to provide a comprehensive overview for clinical use.
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Diagnóstico por Imagen/métodos , Sondas Moleculares/farmacocinética , Tumores Neuroendocrinos/diagnóstico , Sistemas de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos/fisiología , Anticuerpos Monoclonales , Glucosa/metabolismo , Humanos , Redes y Vías Metabólicas/fisiología , Modelos Biológicos , Tumores Neuroendocrinos/metabolismo , Fosfatos/metabolismo , Trazadores Radiactivos , Receptores de Superficie Celular/metabolismo , Receptores de Superficie Celular/fisiologíaRESUMEN
[(11)C]-5-Hydroxytryptophan ([(11)C]HTP) and 6-[(18)F]fluoro-3,4-dihydroxy-l-phenylalanine ([(18)F]FDOPA) are used to image neuroendocrine tumors with positron emission tomography. The precise mechanism by which these tracers accumulate in tumor cells is unknown. We aimed to study tracer uptake via large amino acid transporters, peripheral decarboxylation (inhibited by carbidopa), and intracellular breakdown by monoamine oxidase (MAO). [(11)C]HTP and [(18)F]FDOPA tracer accumulation was assessed in a human neuroendocrine tumor cell line, BON. The carbidopa experiments were done in a tumor-bearing mouse model. Intracellular [(11)C]HTP accumulation was 2-fold higher than that of [(18)F]FDOPA. Cellular transport of both tracers was inhibited by amino-2-norbornanecarboxylic acid. The MAO inhibitors clorgyline and pargyline increased tracer accumulation in vitro. Carbidopa did not influence tracer accumulation in vitro but improved tumor imaging in vivo. Despite lower accumulation in vitro, visualization of [(18)F]FDOPA is superior to [(11)C]HTP in the neuroendocrine pancreatic tumor xenograft model. This could be a consequence of the serotonin saturation of BON cells in the in vivo model.
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5-Hidroxitriptófano/metabolismo , Dihidroxifenilalanina/metabolismo , Tumores Neuroendocrinos/metabolismo , Animales , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Tumores Neuroendocrinos/diagnóstico por imagen , Tumores Neuroendocrinos/patología , Tomografía de Emisión de PositronesRESUMEN
BACKGROUND: Recently, positron emission tomography/computed tomography (PET/CT) has been introduced in the staging of oesophageal cancer. The impact of PET/CT fusion in comparison with side-by-side PET/CT in these tumours, was analyzed. PATIENTS AND METHODS: In 61 patients, 18-F-fluorodeoxyglucose (FDG)-PET and multidetector (md)-CT were performed within a two week interval. Software-fusion of md-CT and FDG-PET was correlated with side-by-side FDG-PET/CT reading by two independent investigators. The gold standard was the pathological outcome or clinical evidence of progression during the first year of follow-up. RESULTS: In 18 patients (18/61; 30%), nodal staging improved with software-fusion. The number of nodal metastases increased in five patients and decreased in four patients, leading to up-staging in one patient (2%) and down-staging in three patients (5%). In nine cases (15%), certainty and localization of metastases improved. However, the number of distant metastases did not change and software-fusion did not have an influence on resectability. CONCLUSION: PET/CT fusion substantially improves detection and localization of nodal metastases and may have an impact on locoregional treatment options.
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Neoplasias Esofágicas/diagnóstico por imagen , Ganglios Linfáticos/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Neoplasias Esofágicas/patología , Femenino , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodosRESUMEN
UNLABELLED: Curative treatment for recurrent medullary thyroid cancer (MTC), diagnosed by rising serum calcitonin, is surgery, but tumor localization is difficult. Therefore, the value of 18F-dihydroxyphenylalanine PET (18F-DOPA PET), 18F-FDG PET, (99m)Tc-V-di-mercaptosulfuricacid (DMSA-V) scintigraphy, and MRI or CT was studied. METHODS: Twenty-one patients with biochemical recurrent or residual MTC underwent 18F-DOPA PET, 18F-FDG PET, DMSA-V scintigraphy, and MRI or CT. Patient- and lesion-based sensitivities were calculated using a composite reference consisting of all imaging modalities. RESULTS: In 76% of all patients with MTC, one or more imaging modalities was positive for MTC lesions. In 6 of 8 patients with a calcitonin level of <500 ng/L, imaging results were negative. In 15 patients with positive imaging results, 18F-DOPA PET detected 13 (sensitivity, 62%; with 4.6 lesions per patient [lpp]). Morphologic imaging (n = 19) was positive in 7 (sensitivity, 37%; 4.7 lpp), DMSA-V (n = 18) in 5 (sensitivity, 28%; 1.1 lpp), and 18F-FDG PET (n = 17) in 4 (sensitivity, 24%; 1.6 lpp). In a lesion-based analysis, 18F-DOPA PET detected 95 of 134 lesions (sensitivity, 71%), morphologic imaging detected 80 of 126 (sensitivity, 64%), DMSA-V detected 20 of 108 (sensitivity, 19%), and 18F-FDG PET detected 48 of 102 (sensitivity, 30%). In 2 of 3 patients with a calcitonin/carcinoembryonic antigen (CEA) doubling time of < or =12 mo, 18F-FDG PET performed better than 18FDOPA PET; in the third patient, 18F-FDG PET was not performed. CONCLUSION: MTC lesions are best detectable when serum calcitonin was >500 ng/L. 18F-DOPA PET is superior to 18F-FDG PET, DMSA-V, and morphologic imaging. With short calcitonin doubling times (< or =12 mo), 18F-FDG PET may be superior.
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Carcinoma Medular/diagnóstico por imagen , Dihidroxifenilalanina , Radioisótopos de Flúor , Tomografía de Emisión de Positrones/métodos , Neoplasias del Timo/diagnóstico por imagen , Adulto , Anciano , Calcitonina/sangre , Antígeno Carcinoembrionario/sangre , Carcinoma Medular/sangre , Carcinoma Medular/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias del Timo/sangre , Neoplasias del Timo/patologíaRESUMEN
PURPOSE: To evaluate and compare diagnostic sensitivity of positron emission tomography (PET) scanning in carcinoid and islet cell tumor patients with a serotonin and a catecholamine precursor as tracers. PATIENTS AND METHODS: Carcinoid (n = 24) or pancreatic islet cell tumor (n = 23) patients with at least one lesion on conventional imaging including somatostatin receptor scintigraphy (SRS) and computed tomography (CT) scan underwent (11)C-5-hydroxytryptophan ((11)C-5-HTP) PET and 6-[F-18]fluoro-L-dihydroxy-phenylalanine ((18)F-DOPA) PET. PET findings were compared with a composite reference standard derived from all available imaging along with clinical and cytologic/histologic information. RESULTS: In carcinoid tumor patients, per-patient analysis showed sensitivities for (11)C-5-HTP PET, (18)F-DOPA PET, SRS, and CT of 100%, 96%, 86%, 96%, respectively, and in islet cell tumors of 100%, 89%, 78%, 87%, respectively. In carcinoid patients, per-lesion analysis revealed sensitivities for (11)C-5-HTP PET, (11)C-5-HTP PET/CT, (18)F-DOPA PET, (18)F-DOPA PET/CT, SRS, SRS/CT, and CT alone of, respectively, 78%, 89%, 87%, 98%, 49%, 73%, and 63% and in islet cell tumors of 67%, 96%, 41%, 80%, 46%, 77%, and 68%, respectively. In all carcinoid patients (18)F-DOPA PET and (11)C-5-HTP PET detected more lesions than SRS (P < .001). (11)C-5-HTP PET was superior to (18)F-DOPA PET in islet cell tumors (P < .0001). In all cases, CT improved the sensitivity of the nuclear scans. CONCLUSION: (18)F-DOPA PET/CT is the optimal imaging modality for staging in carcinoid patients and (11)C-5-HTP PET/CT in islet cell tumor patients.
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5-Hidroxitriptófano , Adenoma de Células de los Islotes Pancreáticos/diagnóstico por imagen , Tumor Carcinoide/diagnóstico por imagen , Dihidroxifenilalanina , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Radioisótopos de Carbono , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Receptores de Somatostatina/metabolismo , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/métodosRESUMEN
BACKGROUND: To assess individual treatment options for patients with carcinoid tumours, accurate knowledge of tumour localisation is essential. We aimed to test the diagnostic sensitivity of 6-[fluoride-18]fluoro-levodopa ((18)F-DOPA PET), compared with conventional imaging methods, in patients with carcinoid tumours. METHODS: In a prospective, single-centre, diagnostic accuracy study, (18)F-DOPA PET with carbidopa pretreatment was compared with somatostatin-receptor scintigraphy (SRS), CT, and combined SRS and CT in 53 patients with a metastatic carcinoid tumour. The performance of all imaging methods was analysed for individual patients, for eight body regions, and for the detection of individual lesions. PET and CT images were fused to improve localisation. To produce a composite reference standard, we used cytological and histological findings; all imaging tests, including secondary assessments for newly found lesions; follow-up; and biochemical data. Sensitivities were calculated and compared. FINDINGS: In patient-based analysis, we recorded sensitivities of 100% (95% CI 93-100) for (18)F-DOPA-PET, 92% (82-98) for SRS, 87% (75-95) for CT, and 96% (87-100) for combined SRS and CT (p=0.45 for (18)F-DOPA PET vs combined SRS and CT). However, (18)F-DOPA PET detected more lesions, more positive regions, and more lesions per region than combined SRS and CT. In region-based analysis, sensitivity of (18)F-DOPA PET was 95% (90-98) versus 66% (57-74) for SRS, 57% (48-66) for CT, and 79% (70-86) for combined SRS and CT (p=0.0001, PET vs combined SRS and CT). In individual-lesion analysis, corresponding sensitivities were 96% (95-98), 46% (43-50), 54% (51-58), and 65% (62-69; p<0.0001 for PET vs combined SRS and CT). INTERPRETATION: If the improved tumour localisation seen with (18)F-DOPA-PET compared with conventional imaging is confirmed in future studies, this imaging method could replace use of SRS, help improve prediction of prognosis, and be used to assess patients' response to treatment for carcinoid tumours.
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Tumor Carcinoide/diagnóstico por imagen , Dihidroxifenilalanina/análogos & derivados , Radiofármacos , Adulto , Anciano , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones , Estudios Prospectivos , Receptores de Somatostatina/metabolismo , Reproducibilidad de los Resultados , Somatostatina/análogos & derivados , Tomografía Computarizada por Rayos XRESUMEN
A carcinoid crisis is a severe complication of the carcinoid syndrome that can arise in patients with advanced metastatic neuroendocrine tumors. It can be initiated by stress, catecholamines, and tumor manipulation. In this article, we report a case in which an injection with the catecholamine tracer 6-18F-fluorodihydroxyphenylalanine, used for PET, induced a carcinoid crisis. Octreotide can be used for treatment and should be available. Tracer injection should be slow.