RESUMEN
Cutaneous melanoma of the eyelid constitutes less than 2% of all eyelid malignancies. Such cases in the pediatric population are even rarer, and exceedingly so in darkly pigmented individuals. A 9-year-old African American boy presented with a left upper eyelid lesion. Biopsy was consistent with deep penetrating melanoma, and the patient underwent a wide local excision and sentinel node biopsy. One upper parotid sentinel node was positive, leading to further parotidectomy and selective neck dissection. The eyelid defect was reconstructed by primary closure after margin clearance. This is the first reported case of cutaneous eyelid melanoma in an African American child with nodal metastasis. Clinical features of melanoma in the pediatric population can be more atypical and higher index of suspicion is indicated. While rare, the diagnosis of melanoma in darkly pigmented patients is still possible and cannot be excluded without a definitive biopsy.
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Neoplasias de los Párpados , Melanoma , Neoplasias Cutáneas , Negro o Afroamericano , Niño , Neoplasias de los Párpados/cirugía , Párpados , Humanos , Metástasis Linfática , Masculino , Melanoma/cirugía , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/cirugíaRESUMEN
AIMS: Gastric heterotopia (GH) has been described throughout the gastrointestinal tract. However, the colorectal region is an extremely rare location for it. We describe the clinicopathological features of GH of the colon, rectum and anus. METHODS AND RESULTS: We identified 33 cases in 20 males and 13 females (median age = 54 years; range = 4 months-73 years). Sites included the rectum (n = 26), anus (n = 4), ileocaecal junction (n = 1), ascending colon (n = 1) and descending colon (n = 1). Presenting symptoms (n = 27) included haematochezia (41%) and altered bowel habits (4%); 15 patients (55%) were asymptomatic. On colonoscopy (n = 31), all appeared as solitary lesions (median size = 6.5 mm, range = 2-55 mm), either as polyps (61%), raised erythematous patches (23%), an ulcer (10%), within a rectal diverticulum (3%) or a haemorrhoid (3%). Patients were managed by polypectomy. One with an associated carcinoma in the area of GH underwent resection. No morbidity related to GH itself was reported following excision. Histologically, heterotopic gastric mucosa was oxyntic (85%), mixed oxyntic and non-oxyntic (12%) and not specified (3%) types. In five patients a pyloric gland adenoma (PGA) arose from heterotopic gastric mucosa, two of which contained a focus of invasive adenocarcinoma. One case had associated surface foveolar-type low-grade dysplasia. Another had associated adenocarcinoma arising from the heterotopic mucosa. One example harboured Helicobacter pylori organisms. CONCLUSIONS: We highlight the features of GH in the distal GIT - the 'outlet patch'. Association with PGA, surface dysplasia and adenocarcinoma suggests that lower tract GH can undergo neoplastic transformation.
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Canal Anal/patología , Coristoma/patología , Enfermedades del Colon/patología , Enfermedades del Recto/patología , Estómago , Adolescente , Adulto , Anciano , Femenino , Humanos , Lactante , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVES: The nested variant of urothelial carcinoma (NVUC) is a rare bladder tumor that may possess a luminal molecular phenotype. We sought to determine whether a small immunohistochemical (IHC) panel using common surrogates for molecular phenotypes would reliably classify a cohort of pure NVUC cases. METHODS: IHC staining with a panel composed of markers for basal subtypes (CK5/6, CK14) and luminal subtypes (FOXA1, GATA3) was performed on pure small NVUC cases (n = 23) and 5 large NVUC cases (n = 5). Scoring of IHC stains was performed semiquantitatively. Individual cases were analyzed using previously reported IHC-based surrogates for molecular subtype. RESULTS: The phenotype of NVUC was classified as luminal from 60.1% (FOXA1+/CK5/6-) to 100% (GATA3+/CK14-) of cases using composite phenotypes. No cases possessed a basal or squamous cell carcinoma-like phenotype. The majority of small NVUC cases (69.5%) showed subset CK5/6 expression distinctly localized to the basal layers of tumor cell nests. Intratumoral heterogeneity was also noted in CK5/6 (21.7% of small NVUC cases) but no other markers. CONCLUSIONS: NVUC appears to express markers of both basal and luminal bladder tumors. Definitive gene expression profiling may be valuable to further characterize this unique histologic variant.
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Biomarcadores de Tumor/metabolismo , Carcinoma de Células Transicionales/patología , Queratina-5/biosíntesis , Queratina-6/biosíntesis , Neoplasias de la Vejiga Urinaria/patología , Anciano , Carcinoma de Células Transicionales/clasificación , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias de la Vejiga Urinaria/clasificaciónRESUMEN
A novel DEK-AFF2 fusion was recently reported in 4 nonkeratinizing squamous cell carcinomas of the sinonasal region and skull base, including 1 with exceptional response to immunotherapy, but it is not yet clear if this rearrangement defines a unique clinicopathologic category or represents a rare event. This study aims to characterize a larger cohort of carcinomas with DEK-AFF2 fusions to assess whether they truly constitute a distinctive entity. Among 27 sinonasal and skull base nonkeratinizing squamous cell carcinoma that were negative for human papillomavirus and Epstein-Barr virus, RNA sequencing identified DEK-AFF2 fusions in 13 cases (48%). Nine were centered in the nasal cavity, 2 in the middle ear/temporal bone, 1 in the nasopharynx, and 1 in the orbit. These tumors displayed recurrent histologic features including (1) complex endophytic and exophytic, frequently papilloma-like growth, (2) transitional epithelium with eosinophilic to amphophilic cytoplasm, (3) absent or minimal keratinization with occasional compact keratin pearls, (4) monotonous nuclei, and (5) prominent tumor-infiltrating neutrophils or stromal lymphocytes. This appearance not only overlaps with high-grade basaloid sinonasal carcinomas but also with benign papillomas and tumors reported as low-grade papillary Schneiderian carcinoma. However, DEK-AFF2 carcinomas showed frequent local recurrence, cervical lymph node metastases, and distant metastasis with 2 deaths from disease, confirming they are aggressive malignancies despite relatively bland histology. Overall, the distinctive molecular, histologic, and clinical features of DEK-AFF2 carcinomas suggest they represent a unique entity in the sinonasal region. This tumor merits increased pathologic recognition to better understand its prognostic and therapeutic implications.
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Biomarcadores de Tumor/genética , Proteínas Cromosómicas no Histona/genética , Fusión Génica , Proteínas Nucleares/genética , Proteínas Oncogénicas/genética , Neoplasias de los Senos Paranasales/genética , Proteínas de Unión a Poli-ADP-Ribosa/genética , Neoplasias de la Base del Cráneo/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/análisis , Femenino , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Hibridación in Situ , Masculino , Persona de Mediana Edad , Neoplasias de los Senos Paranasales/química , Neoplasias de los Senos Paranasales/patología , Fenotipo , RNA-Seq , Neoplasias de la Base del Cráneo/química , Neoplasias de la Base del Cráneo/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/química , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Adulto JovenRESUMEN
Ischemic colitis (IC) associates with older age, hypertension, and heart disease, among others. Young-onset IC is rare. We aimed to delineate clinical characteristics of young patients (<40 years) with IC. Cases from 1984 to 2017 were re-reviewed. Of the 60 cases available, 52% (n = 31) had histologic features of IC. Fifty-five percent were female with a mean age of 32 (range = 14-40) years. Fifty-eight percent (n = 18) were resections. The most common presentations were diarrhea and abdominal pain. Three teenagers had IC associated with prior surgery, volvulus, and constipation. In the 21- to 40-year group, 43% (n = 12) lacked clinical associations. A second subset (n = 6, 21%) had histories of immune dysregulation (lupus, dermatomyositis, vasculitis) and poorly controlled HIV/AIDS (n = 5, 18%). Smoking and cocaine were endorsed by 1 and 2 patients, respectively. One patient had premature atherosclerosis while another had HMG Co-A lyase deficiency. Vasculitis was identified in 22% of the resections and in none of the biopsies. Nineteen percent of patients died (n = 6) from complications of IC, all treated surgically, including 1 patient previously misdiagnosed as ulcerative colitis; 2 patients died of unrelated causes. While rare before 20 years of age, IC in teenagers relates to mechanical issues and is rare in children. Associations in young adults include immune dysregulation, cocaine and cigarette use, and premature atherosclerosis. Our retrospective cohort had a surgical mortality rate within the range reported by others, highlighting the importance of accurate diagnosis in young individuals.
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Edad de Inicio , Colitis Isquémica/diagnóstico , Colon/patología , Mucosa Intestinal/patología , Dolor Abdominal/etiología , Dolor Abdominal/cirugía , Adolescente , Adulto , Factores de Edad , Biopsia , Colectomía , Colitis Isquémica/complicaciones , Colitis Isquémica/mortalidad , Colitis Isquémica/cirugía , Colon/inmunología , Colon/cirugía , Estreñimiento/etiología , Diarrea/etiología , Diarrea/cirugía , Diagnóstico Precoz , Femenino , Estudios de Seguimiento , Humanos , Mucosa Intestinal/inmunología , Masculino , Estudios Retrospectivos , Adulto JovenRESUMEN
INTRODUCTION: Colon biopsies are among the most frequently examined specimens by pathologists. Many pathology practices, ours included, review upfront levels on all gastrointestinal biopsies. In our experience, when a lesion is present on specimens labeled "colon polyp," it is readily identified on the first level. To test our hypothesis, we re-reviewed 500 cases in which a lesion was identified histologically and determined if the diagnosis could be made on the first level. Furthermore, we examined 50 additional cases of high-grade dysplasia/carcinoma to determine if the higher-grade component was also present on the first level. MATERIALS AND METHODS: Cases were retrieved for lesions that could account for a colon polyp clinically, and the first level was examined to determine if lesional tissue was present on the first level. Fifty additional cases of higher-grade lesions were included to ensure higher-grade lesions were present on the first level. RESULTS: Overall, 497/500 (99.4%) of the non-high-grade lesions were present on the first level, whereas 3/500 (0.6%) required the additional level for diagnosis. All 50 high-grade lesions were present on the first level examined. DISCUSSION: Many pathology practices routinely order upfront levels on all gastrointestinal biopsies, often generating 2 or 3 slides. Additional slides increase costs, increase the likelihood of laboratory-generated errors, and can waste limited tissue on small biopsies for which ancillary studies may be necessary. Our study showed that a single level is sufficient in the overwhelming majority of cases in which a lesion is identified histologically.
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Pólipos del Colon/diagnóstico , Pólipos del Colon/patología , Patología Clínica/métodos , HumanosRESUMEN
CONTEXT.: Intraoperative pathology consultation is an important tool for many surgical procedures and is deemed appropriate when the pathology result immediately alters surgical management. OBJECTIVE.: To evaluate the utility of intraoperative gross examinations of colorectal resections and to better understand the associated costs. DESIGN.: The pathology database of our institution was searched for colorectal resections for primary disease, and those cases were separated into 3 categories: frozen section performed, intraoperative gross examination performed, and no intraoperative consultation. We reviewed 270 cases during a 15-month period. RESULTS.: Of the 270 cases, 200 (74.1%) had an intraoperative gross examination. In 34 of the 200 cases (17%), additional specimens were taken and, therefore, required operative note review to ascertain whether the additional specimens taken were based on the findings from the intraoperative gross examination. After reviewing the operative notes for those 34 cases, none (0%) were a result of the gross findings reported. The average associated time for intraoperative gross examinations was 27.67 minutes (including transport). The billable costs exceeded $7000 during the study period, and the cost of the pathology assistant's time per case was $22.10. CONCLUSIONS.: Our study demonstrates that no change in surgical management was a result of gross examination of colorectal resection specimens and that the associated costs were significant. Decreasing unnecessary consultations will directly save the health care system money by eliminating billable services and will also increase the efficiency of the pathology department by reducing the opportunity costs for the time of the pathologist and the pathology staff.
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Neoplasias Colorrectales/patología , Neoplasias Colorrectales/cirugía , Patología Quirúrgica/economía , Patología Quirúrgica/métodos , Análisis Costo-Beneficio , Humanos , Periodo Intraoperatorio , Derivación y Consulta/economía , Estudios RetrospectivosRESUMEN
Histologic changes following radiation therapy to the prostate include multilayering of glands, atrophy, squamous metaplasia, and often marked random nuclear atypia. We have seen multiple consultation cases where the differential diagnosis of these radiated prostate glands included urothelial carcinoma, with multilayered to solid-appearing proliferations that were positive by immunohistochemistry for GATA3. To formally investigate this issue, 30 cases of benign prostate tissue with radiation atypia, from 1990 to 2015, were obtained from our institution. Cases were evaluated by immunohistochemistry for the prostate-specific markers prostate-specific antigen (PSA), P501S (Prostein), and NKX3.1 and urothelial markers GATA3 and uroplakin 2. GATA3 was positive in 100% of cases, with 70% showing moderately strong to strong staining in a mostly patchy manner within a gland. PSA was positive in 93.3% of cases, with 89.2% showing moderately strong to strong staining in a mostly diffuse manner. P501S was positive in 96.7% of cases, with 93.1% showing moderately strong to strong staining in a mostly patchy manner. NKX3.1 was positive in 82.8% of cases, with 33.3% showing moderately strong to strong staining in a mostly patchy manner. Uroplakin 2 was negative in 100% of cases. Our findings highlight that GATA3 is often positive in benign prostate glands with radiation atypia, which along with the morphologic features present a pitfall for the misdiagnosis of urothelial carcinoma. A combination of PSA and P501S is the best prostate-specific panel for use in radiated prostate, with the caveat that they are often patchy and do not stain all radiated glands.
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Biomarcadores de Tumor/análisis , Carcinoma/química , Factor de Transcripción GATA3/análisis , Próstata/química , Próstata/efectos de la radiación , Neoplasias de la Próstata/química , Urotelio/química , Biopsia , Carcinoma/patología , Diagnóstico Diferencial , Errores Diagnósticos , Proteínas de Homeodominio/análisis , Humanos , Inmunohistoquímica , Calicreínas/análisis , Masculino , Valor Predictivo de las Pruebas , Próstata/patología , Antígeno Prostático Específico/análisis , Neoplasias de la Próstata/patología , Factores de Transcripción/análisis , Uroplaquina II/análisis , Urotelio/patologíaRESUMEN
The oral cavity and oropharynx have historically been viewed as a single anatomic compartment of the head and neck. The practice of combining the oral cavity and oropharynx has recently been revised, largely owing to the observation that human papillomavirus (HPV)-related carcinogenesis has a strong predilection for the oropharynx but not the oral cavity. The purpose of this study was to determine whether HPV is evenly distributed across squamous cell carcinomas of the oropharynx including those sites that do not harbor tonsillar tissues such as the soft palate. A search of the medical records of the Johns Hopkins Hospital identified 32 primary squamous cell carcinomas of the soft palate (n=31) and posterior pharyngeal wall (n=1). All were evaluated with p16 immunohistochemistry and high-risk HPV in situ hybridization (ISH) (29 by RNA ISH and 3 by DNA ISH). For comparison, we also reviewed the medical records to obtain the HPV status of patients who had undergone HPV testing of primary tonsillar carcinomas over the same time interval as part of their clinical care. High-risk HPV as detected by ISH was present in just 1 (3.1%) of the 32 oropharyngeal squamous cell carcinomas, including 1 of 2 p16-positive carcinomas. The difference in HPV detection rates between tonsillar and nontonsillar sites was significant (1/32, 3.1% vs. 917/997, 92%; P<0.0001). HPV is not frequently detected in squamous cell carcinomas arising from nontonsillar regions of the oropharynx. Indeed, squamous cell carcinomas of the soft palate more closely resemble those arising in the oral cavity than those arising in areas of the oropharynx harboring tonsillar tissue. This finding not only further sharpens our understanding of site-specific targeting by HPV, but may have practical implications regarding HPV testing and even the way the oral vault is oncologically compartmentalized to partition HPV-positive from HPV-negative cancers.
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Carcinoma de Células Escamosas/virología , Neoplasias de Cabeza y Cuello/virología , Neoplasias Orofaríngeas/virología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Anciano , Baltimore , Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/patología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/análisis , ADN Viral/genética , Femenino , Neoplasias de Cabeza y Cuello/química , Neoplasias de Cabeza y Cuello/patología , Interacciones Huésped-Patógeno , Pruebas de ADN del Papillomavirus Humano , Humanos , Inmunohistoquímica , Hibridación in Situ , Masculino , Registros Médicos , Persona de Mediana Edad , Neoplasias Orofaríngeas/química , Neoplasias Orofaríngeas/patología , Paladar Blando/patología , Paladar Blando/virología , Tonsila Palatina/patología , Tonsila Palatina/virología , Papillomaviridae/genética , Infecciones por Papillomavirus/patología , ARN Viral/genética , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
BACKGROUND: We report a case in which the extraintestinal manifestations of inflammatory bowel disease preceded development of gastrointestinal symptoms by nearly 9 months in the context of an unusual autoantibody panel, mimicking granulomatosis with polyangiitis. This case highlights the intricacies and overlap of autoimmune diseases, and illustrates an interesting clinical phenotype: cytoplasmic anti-neutrophil cytoplasmic antibody positive inflammatory bowel disease with predominantly extraintestinal manifestations. Perinuclear anti-neutrophil cytoplasmic antibody positivity has been frequently reported in association with inflammatory bowel disease, but cytoplasmic anti-neutrophil cytoplasmic antibody positivity is uncommon. CASE PRESENTATION: A 54-year-old African-American man presented to our internal medicine resident clinic at the Johns Hopkins Hospital with several months of systemic inflammatory features: anterior uveitis, auricular chondritis, monoarthritis, fever, and weight loss. He did not have a primary care physician due to lack of health insurance and had been seen in our emergency department several times over the past year. These features fit nicely with a diagnosis of granulomatosis with polyangiitis, especially given positive cytoplasmic anti-neutrophil cytoplasmic antibodies. However, 9 months into his clinical course he developed hematochezia with perirectal abscess and fistula. A colonoscopy with biopsy confirmed a diagnosis of inflammatory bowel disease. CONCLUSIONS: This case highlights the fact that extraintestinal manifestations may precede gastrointestinal symptoms of inflammatory bowel disease for months, which may delay diagnosis if not understood and recognized. It further highlights an interesting disease phenotype that has not been widely reported, but may deserve further study. Lastly, the case stresses the importance of the internist in identifying a unifying diagnosis in a slowly evolving clinical process with the assistance of subspecialists. In this respect, the case is of interest to general internists, as well as rheumatologists and gastroenterologists.
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Granulomatosis con Poliangitis , Enfermedades Inflamatorias del Intestino/diagnóstico , Colonoscopía , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A 77-year-old man with chronic obstructive lung disease who was on steroids, presented to the hospital after a fall with subacute headaches and ataxia. During the patient's hospital course, his clinical condition deteriorated with myoclonic jerks, fevers and severe encephalopathy. An extensive workup, including EEG, brain MRI and lumbar puncture, revealed possible Creutzfeldt-Jakob disease. Unfortunately, the patient failed to improve and died 12â days after admission. A brain-only autopsy revealed he had acute histoplasma meningitis with patchy superficial cerebritis.
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Síndrome de Creutzfeldt-Jakob , Histoplasmosis/diagnóstico , Meningitis/diagnóstico , Meningitis/microbiología , Anciano , Autopsia , Encéfalo/patología , Diagnóstico Diferencial , Resultado Fatal , Histoplasma , Humanos , MasculinoRESUMEN
Despite the recommendation of expert gastrointestinal pathologists, private and academic centers (including our own) have continued to use ancillary stains for identification of Helicobacter pylori. For a 1-month period, gastric biopsies were prospectively evaluated for H pylori using routine hematoxylin and eosin (H&E) and a reflex Diff-Quik stain. During this time, 379 gastric biopsies were collected on 326 patients. H pylori organisms were prospectively identified in 23 (7%) patients, all of whom had superficial dense lymphoplasmacytic inflammation expanding the lamina propria. An additional 2 patients with neutrophilic inflammation were found to have H pylori by immunohistochemical staining. One patient diagnosed as having normal gastric mucosa was retrospectively found to have inflammation with rare H pylori organisms originally overlooked on both H&E and Diff-Quik but later identified on immunostain (0.5%). No patients with chemical gastritis (16%) or chronic inflammation (27%) were found to have H pylori. During the study month, 9 immunostains for H pylori were performed in addition to the 379 Diff-Quik. After discontinuation of reflex Diff-Quik, approximately 20 immunostains are performed for H pylori each month, which decreases technical time spent for processing gastric biopsies and reduces cost to the health care system. In our population with a low prevalence of H pylori, reflex staining for organisms is not cost-effective. The organisms can be seen on routine H&E; when suspicious superficial or active inflammation is present without visible organisms, immunohistochemical stains will confirm presence or absence within a day. Discontinuation of up-front ancillary studies is cost-effective without compromising patient care.
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Centros Médicos Académicos/economía , Técnicas Bacteriológicas/economía , Pruebas Diagnósticas de Rutina/economía , Costos de la Atención en Salud , Infecciones por Helicobacter/economía , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Coloración y Etiquetado/economía , Estómago/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Baltimore , Biopsia/economía , Niño , Preescolar , Ahorro de Costo , Análisis Costo-Beneficio , Reacciones Falso Negativas , Femenino , Infecciones por Helicobacter/patología , Humanos , Inmunohistoquímica/economía , Lactante , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Reproducibilidad de los Resultados , Coloración y Etiquetado/métodos , Estómago/patología , Adulto JovenRESUMEN
OBJECTIVES: The spinal cord is known to be innervated with dopaminergic cells with catecholaminergic projections arising from the medulla and pons and dopaminergic transmission in the spinal cord is vital for sensory and motor function. Our goal was to evaluate and compare the imaging capability of dopamine D2/D3 receptors in the rat spinal cord using PET ligands (18)F-fallypride and (11)C-fallypride. METHODS: Male Sprague-Dawley rats were used in all in vitro and in vivo studies. Spinal cord and brain sections were used for in vitro autoradiography and ex vivo autoradiography. For in vivo studies animals received a (18)F-fallypride scan or a (11)C-fallypride PET scan. The spinal cord and the brain were then harvested, flash-frozen and imaged ex vivo. For in vivo analysis Logan plots with cerebellum as a reference was used to evaluate binding potentials (BP). Tissue ratios were used for ex vivo analysis. Drug effects were evaluated using clozapine, haloperidol and dopamine were evaluated on spinal cord sections in vitro. RESULTS: In vitro studies showed (18)F-fallypride binding to superficial dorsal horn (SDH), dorsal horn (DH), ventral horn (VH) and the pars centralis (PC). In the cervical section, the greatest amount of binding appeared to be in the SDH. Ex vivo studies showed approximately 6% of (18)F-fallypride in SDH compared to that observed in the striatum. In vivo analysis of both (18)F-fallypride and (11)C-fallypride in the spinal cord were comparable to that in the extrastriatal regions. Haloperidol and clozapine displaced more than 75% of the (18)F-fallypride in spinal cord sections. CONCLUSIONS: Our studies showed (18)F-fallypride and (11)C-fallypride binding in the spinal cord in vitro and in vivo. The binding pattern correlates well with the known distribution of dopamine D2/D3 receptors in the spinal cord.
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Benzamidas/farmacocinética , Radioisótopos de Flúor/farmacocinética , Radiofármacos/farmacocinética , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Médula Espinal/diagnóstico por imagen , Animales , Benzamidas/química , Técnicas In Vitro , Masculino , Tomografía de Emisión de Positrones/métodos , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D2/química , Receptores de Dopamina D3/antagonistas & inhibidores , Médula Espinal/metabolismoAsunto(s)
Carcinoma de Células Escamosas/epidemiología , Neoplasias Orofaríngeas/epidemiología , Infecciones por Papillomavirus/epidemiología , Infecciones por Papillomavirus/virología , Factores de Edad , Anciano , Baltimore/epidemiología , Carcinoma de Células Escamosas/virología , Femenino , Humanos , Inmunohistoquímica , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/virología , Factores de RiesgoRESUMEN
RATIONALE AND OBJECTIVES: The aim of this study was to compare precontrast and postcontrast renal diffusion-weighted images for signal intensity (SI), apparent diffusion coefficient (ADC), and lesion conspicuity. MATERIALS AND METHODS: In 62 patients (mean age, 54 ± 29; 29 men, 33 women) precontrast and postcontrast (0.1 mmol/kg of extracellular gadolinium-based contrast medium; mean, 3.3 ± 0.9 minutes], diffusion-weighted images at b values of 50 and 400 s/mm² were compared (3 T). The SI, signal-to-noise ratio, and ADC of the renal cortex, medulla, and lesions were measured. Lesion contrast-to-noise ratios (against the medulla and cortex) were calculated. RESULTS: Postcontrast medullary SI decreased by 50% and cortical SI decreased by 33% and 39% on images at b = 50 s/mm² and b = 400 s/mm², respectively (P < .0001). The SI and signal-to-noise ratio of lesions did not change significantly after contrast, but lesion-medullary contrast-to-noise ratio was increased by 50% at both b = 50 s/mm² and b = 400 s/mm² (P < .005 and P = .0005, respectively) following contrast. Qualitative postcontrast lesion conspicuity was improved, with average scores of 2.8 ± 0.9 for all lesions (κ = 0.7 ± 0.08) and 3.2 ± 0.9 for solid lesions (κ = 0.82 ± 0.1). The ADC of renal cortex decreased (P = .03), but the ADC of renal medulla or renal lesions did not significantly change. CONCLUSION: Postcontrast diffusion-weighted imaging causes a significant decrease in renal parenchymal signal without a significant change in lesion signal, resulting in increased lesion conspicuity.