RESUMEN
BACKGROUND: Lesions that are histologically classified as precursors of cervical cancer, which are often referred to as squamous intraepithelial lesions (SILs), represent a heterogeneous clinical entity that can be associated with many different types of human papillomaviruses (HPVs) and have a variable biologic behavior. Approximately one half of low-grade SILs behave as non-neoplastic, productive viral lesions that frequently regress spontaneously, whereas the other half behave as neoplasms and either persist or progress to a histologically higher grade lesion. Identification of biomarkers that reliably differentiate those low-grade SILs with the properties of a non-neoplastic viral infection from those with the properties of neoplasia would provide a more rational basis for decisions about disease management. Since monoclonality is a hallmark of neoplasia irrespective or organ site, clonal status might represent one such biomarker. PURPOSE: To better understand the pathobiology of SILs, we analyzed the clonality of low-grade and high-grade SILs and compared their clonal status with their associated HPV types. METHODS: One hundred forty formalin-fixed, paraffin-embedded cervical biospy and loop electrosurgical specimens, originally diagnosed as SILs, were obtained from the pathology archives of both the Columbia-Presbyterian Medical Center and Kyto Diagnostics in New York. Clonality was determined with the use of a polymerase chain reaction (PCR) based method that detects nonrandom X-chromosome inactivation. This PCR-method amplifies a polymorphic region of the androgen receptor gene that is flanked by several differentially methylated enzyme sites. The same tissue was also analyzed for HPV DNA with the use of PCR and both L1 and E6 "consensus" primers. RESULTS: All 25 evaluable cases of high-grade SILs were determined to be monoclonal. Although 54 (68%) of 79 evaluable low-grade SILs were monoclonal, 25 (32%) of 79 low-grade SILs were polyclonal. A strong association was observed between HPV type and clonal status, with a total of 71 (47 low-grade and 24 high-grade) SILs determined to be monoclonal and containing HPV types 16, 18, 31, 33, 35, 39, 45, 56, 58, or 65. In contrast, 22 (92%) of the 24 low-grade SILs that contained another type of HPV were polyclonal (Fisher's exact test, two-sided, P-.001). CONCLUSIONS: Our findings suggest that the histopathologic entity termed low-grade SIL consists of two different types of lesions that are biologically distinct. One lesion is monoclonal and is associated with HPV types 16, 18, 31, 33, 35, 39, 45, 56, 58, or 65. The second types of low-grade SIL is polyclonal and is associated with other types of HPV.
Asunto(s)
Carcinoma de Células Escamosas/virología , Papillomaviridae/clasificación , Infecciones por Papillomavirus , Infecciones Tumorales por Virus , Displasia del Cuello del Útero/virología , Neoplasias del Cuello Uterino/virología , Alelos , Secuencia de Bases , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , ADN Viral/análisis , ADN Viral/genética , Compensación de Dosificación (Genética) , Femenino , Formaldehído , Humanos , Datos de Secuencia Molecular , Papillomaviridae/genética , Adhesión en Parafina , Reacción en Cadena de la Polimerasa , Fijación del Tejido , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/genética , Displasia del Cuello del Útero/patologíaRESUMEN
Ovarian carcinoma can arise synchronously from multiple independent sites and metastasize widely. Therefore, it is frequently unclear whether bilateral tumors represent two independent primaries or one primary and a metastasis. We have used X chromosome inactivation of the androgen receptor gene and microsatellite instability at four chromosomal loci to evaluate the clonal origin of 39 bilateral ovarian carcinomas. An identical monoclonal pattern was found bilaterally in all cases including 10 stage I bilateral ovarian carcinomas. Microsatellite alterations were identified in three cases, and in all three, identical alterations were present in tumor tissue from both ovaries. These results suggest that bilateral ovarian carcinomas evolve as unifocal neoplasias and that metastatic dissemination can occur early in the course of the disease.
Asunto(s)
ADN de Neoplasias/genética , ADN Satélite/genética , Compensación de Dosificación (Genética) , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Cromosoma X , Secuencia de Bases , Femenino , Humanos , Datos de Secuencia Molecular , Mutación , Estadificación de Neoplasias , Polimorfismo Genético , Receptores Androgénicos/genéticaRESUMEN
To evaluate the importance of high-risk human papillomavirus (HPV) types in in situ and invasive adeno- and adenosquamous carcinomas (ACISs/ACs, and ASCISs/ASCs) of the cervix uteri, we analyzed HPV infection and HPV 16- and HPV 18 E6/E7 oncogene expression in different histologic subtypes. Using the polymerase chain reaction (PCR) technique, 29 of 33 (88%) ACISs, 2 of 2 (100%) ASCISs, 46 of 54 (85%) ACs, and 8 of 10 (80%) ASCs were found to be HPV 16- and/or HPV 18-positive. In 25 of 35 (71%), 10 of 35 (29%), and 4 of 35 (11%) ACISs/ASCISs, HPV 16, HPV 18, and HPV 16 and HPV 18 were detected, respectively. Invasive ACs/ASCs were more frequently infected with HPV 18 (36 of 64, 56%) than with HPV 16 (28 of 64, 44%). Ten (16%) of these cases were positive for HPV 16 and HPV 18. In ACISs/ASCISs, HPV 16 oncogene expression predominated (62%) relative to HPV 18 (25%) expression, whereas in invasive ACs/ASCs, only 21% of the cases expressed HPV 16, but 48% of the cases expressed HPV 18 oncogenes. Thus, detection of HPV 18 in ACISs/ASCISs might be associated with an increased risk of progression. HPV oncogene expression was not dependent on histologic subtype of in situ or invasive AC. Normal glandular epithelia and glandular dysplasias (GDs, n = 4) were always negative concerning HPV oncogene expression. In HPV 16- and HPV 18-double-infected cases, HPV 18 oncogene expression was most frequently detected, and we did not find a coexpression of HPV 16- and HPV 18-specific oncogenes in purely glandular lesions or in cases with an additional CIN (cervical intraepithelial neoplasia) II or CIN III. HPV E6/E7 expression of the same HPV type in both in situ or invasive ACs and associated CIN II/III suggest that these lesions might be histogenetically related.
Asunto(s)
Adenocarcinoma/virología , Expresión Génica , Genes Virales/genética , Oncogenes/genética , Papillomaviridae/genética , Neoplasias del Cuello Uterino/virología , Adenocarcinoma/patología , Femenino , Humanos , Invasividad Neoplásica , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/virologíaRESUMEN
OBJECT: In recent reports, 6 to 19% of meningiomas have been classified as atypical or anaplastic/malignant. Some atypical and anaplastic meningiomas appear to arise from benign tumors by progression. Telomerase activation has recently been associated with malignant progression of human tumors. The authors have investigated a series of benign, atypical, and anaplastic/malignant meningiomas for telomerase activity and expression of the telomerase catalytic subunit human telomerase reverse transcriptase (hTERT). METHODS: A quantitative telomeric repeat amplification protocol was used to detect telomerase enzyme activity in seven (21%) of 34 benign, but in nine (75%) of 12 atypical and in seven (100%) of seven anaplastic/malignant meningiomas. Very high levels of telomerase activity were observed only in highly aggressive tumors. Messenger (m)RNA expression of the catalytic subunit hTERT was found in 11 (33%) of 33 benign, 12 (92%) of 13 atypical, and all seven anaplastic/malignant tumors. All telomerase-positive lesions were also positive for hTERT mRNA, whereas no telomerase activity was detected in six (21%) of 29 hTERT-positive tumors. This indicates that upregulation of hTERT is the rate-limiting step for telomerase activation in the majority of meningiomas. Expression of telomerase and hTERT was seen in all four tumors with gross brain invasion. All recurrent tumors or meningiomas recurring during follow up expressed hTERT. CONCLUSIONS: The results are consistent with a role for telomerase activation during the development of malignancy in meningiomas. Hence, expression of telomerase activity and hTERT might prove to be potentially useful markers for the evaluation of these tumors.
Asunto(s)
Dominio Catalítico/genética , Neoplasias Meníngeas/enzimología , Meningioma/enzimología , ARN , Telomerasa/genética , Telomerasa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Anaplasia , Proteínas de Unión al ADN , Progresión de la Enfermedad , Activación Enzimática , Femenino , Estudios de Seguimiento , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Meningioma/genética , Meningioma/patología , Persona de Mediana Edad , Invasividad Neoplásica , Recurrencia Local de Neoplasia/enzimología , Recurrencia Local de Neoplasia/genética , ARN Mensajero/genética , Regulación hacia ArribaRESUMEN
OBJECTIVE: This study was performed to assess the diagnostic and quantifying ability of digital subtraction images for simulated apical root resorption, as well as to compare the diagnostic accuracy of conventional intraoral radiographs with digital subtraction images for this condition. STUDY DESIGN: Digital and intraoral radiographs of 10 sound maxillary central incisors and those with simulated apical root resorption were taken with varying horizontal and vertical angulations of the x-ray beam. Paired t tests were used to compare the lengths of the sound teeth on the images with their actual lengths, and the estimated amount of simulated apical root resorption was compared with the actual amount of tooth loss by means of Emago software. The diagnostic accuracy for detecting lesions was also evaluated on conventional intraoral radiographs and digital subtraction images through receiver operating characteristic (ROC) analysis. RESULTS: There were no statistically significant differences between the actual lengths and those measured on the reconstructed images of the sound teeth. The calculated amounts of apical root resorption showed no statistically significant differences in comparison with the actual amounts (P >.05). The diagnostic accuracy of the conventional intraoral radiographs in detecting the lesions was low (ROC area = 0.6446). CONCLUSION: A quantitative analysis of small amounts of apical root resorption can be performed by means of digital subtraction radiography.
Asunto(s)
Radiografía Dental Digital/métodos , Resorción Radicular/diagnóstico por imagen , Técnica de Sustracción , Humanos , Incisivo/diagnóstico por imagen , Curva ROC , Interpretación de Imagen Radiográfica Asistida por Computador , Radiografía Dental/métodos , Reproducibilidad de los Resultados , Validación de Programas de Computación , Ápice del Diente/diagnóstico por imagenRESUMEN
OBJECTIVES: We sought to calculate the size and the computed tomography (CT) number of normal parotid and submandibular glands and to evaluate their relationship with respect to sex, age, and obesity in the Korean population. STUDY DESIGN: The authors investigated the axial CT images of 42 healthy volunteers. The maximum cross-sectional area (MCSA) was used as an indicator of the size of the gland. Three regions of interest on axial scans were selected to calculate the mean CT number. RESULTS: There was a significant decrease in the mean MCSA of the submandibular gland and the CT number of both glands with age. The MCSA of the submandibular gland in males was larger than that in females. There was a close correlation between the parotid and the submandibular glands with respect to the CT number, as well as between the left and right glands with respect to the MCSA and the CT number. The body mass index was positively correlated with the MCSA of the parotid gland, whereas the body mass indexes and the CT numbers of both glands were negatively correlated. CONCLUSIONS: Both age and obesity are closely correlated with the size and the CT number of the major salivary glands. Moreover, the correlation between the CT numbers of the parotid and the submandibular glands may be used for diagnostic purposes.
Asunto(s)
Glándula Parótida/diagnóstico por imagen , Glándula Submandibular/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Factores de Edad , Anciano , Anatomía Transversal , Índice de Masa Corporal , Femenino , Humanos , Corea (Geográfico) , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico por imagen , Análisis de Regresión , Factores Sexuales , Estadísticas no ParamétricasAsunto(s)
Soluciones para Diálisis , Inhibidores Enzimáticos/química , Ácido Penicilánico/análogos & derivados , Penicilinas/química , Diálisis Peritoneal Ambulatoria Continua , Piperacilina/química , Inhibidores de beta-Lactamasas , Estabilidad de Medicamentos , Humanos , Ácido Penicilánico/química , TazobactamRESUMEN
The majority of patients with epithelial ovarian cancer (EOC) are diagnosed with advanced disease involving sites such as the upper abdomen, pleural space, and paraaortic lymph nodes. The standard therapy for advanced disease requires maximal cytoreductive surgery followed by postoperative platinum- and taxane-based chemotherapy. Despite maximal primary surgical effort and postoperative standard chemotherapy long-term survival of patients with advanced stage III or IV disease ranges from 30% to less than 10% due to early and late relapse or primary progressive disease. Facing the highly lethal nature of epithelial ovarian carcinoma, the clinical course of advanced disease is difficult to predict in an individual patient. This heterogeneity of clinical outcome in patients with ovarian carcinoma suggests that reliable prognostic and/or predictive factors would be of potential clinical value and new treatment options are warranted in the future. In the light of recently published studies we summarize the clinical features and the diagnostic, operative and postoperative management of epithelial ovarian carcinoma. We furthermore address the importance of the pathologist during the clinical course of patients with ovarian carcinoma. The issue of timing between surgery and chemotherapy in the setting of neoadjuvant chemotherapy treatment of advanced ovarian carcinoma is being highlighted as well as the significance of new diagnostic and therapeutic options with regard to accurate predictive markers, that might identify patients who are appropriate candidates for novel therapeutic approaches.
Asunto(s)
Carcinoma/patología , Neoplasias Ováricas/patología , Antineoplásicos , Carcinoma/tratamiento farmacológico , Carcinoma/mortalidad , Carcinoma/cirugía , Quimioterapia Adyuvante , Terapia Combinada , Femenino , Humanos , Estadificación de Neoplasias , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/cirugía , Tasa de SupervivenciaRESUMEN
The research reported here is a first step toward the building of a general theory of development in Asia. The specific goals involved are: (1) to delineate major patterns of development in Asia; (2) to examine the fluctuation of each nation's pattern scores; and (3) to evaluate trends in Asia as a system.
RESUMEN
Cervical cancer develops from well-defined precursor lesions referred to as either cervical intraepithelial neoplasia or squamous intraepithelial lesions. It is now known that specific types of human papillomaviruses (HPV) are the principal etiologic agents for both cervical cancer and its precursors. The high-oncogenic-risk HPV types associated with invasive cervical cancer produce two oncoproteins, designated E6 and E7, which interact with endogenous cell cycle regulatory proteins, including p53 and Rb. The interaction of virally derived and endogenous cellular proteins converges in deregulation of cell cycle progression and appears to be critical for the development of cervical cancers. However, the development of cervical cancer is a multistep process that cannot be explained simply by infection with specific types of HPV. One additional event that appears to play a role in tumor progression is integration of HPV DNA into the host genome. Integration of HPV DNA frequently disrupts the E2 open reading frames, resulting in overexpression of the E6 and E7 oncoproteins and possibly causing genomic instability. Additional cofactors and mutational events may be important in the pathogenesis of invasive cervical cancers and may include chromosomal rearrangements, loss of constitutional heterozygosity, and proto-oncogene activation.
Asunto(s)
Papillomaviridae/genética , Lesiones Precancerosas/genética , Infecciones Tumorales por Virus/genética , Neoplasias del Cuello Uterino/genética , Transformación Celular Viral , Aberraciones Cromosómicas , Femenino , Humanos , Proteínas Oncogénicas Virales/genética , Papillomaviridae/clasificación , Proto-Oncogenes Mas , Proto-Oncogenes , Neoplasias del Cuello Uterino/etiologíaRESUMEN
Cervical carcinomas and their precursors (cervical dysplasia, CIN1-3) are associated with human papillomavirus (HPV) infections. Epidemiological and in vitro-studies have shown that some of the genital HPV types, the high risk-types 16, 18, 31 etc., code for proteins (E6/E7) which strongly influence the cell cycle and genome stability. Progression from weak to severe dysplasia and to invasive cancer is associated with increasing expression of these viral oncogenes. Which additional cofactors contribute to progression of some dysplasias to carcinomas is still a matter of investigation. Recent results point to genetic predisposition (p53 polymorphism), cellular immune reaction, and cytokine expression. For HPV detection in cervical swabs and biopsies two highly sensitive and reliable systems (PCR, Hybrid Capture system) are available. Although classical histological methods are sufficient for the diagnosis of high-grade lesions and invasive cancer, HPV testing might give valuable diagnostic and prognostic clues especially in cases of unclear cytology (ASCUS) or weak dysplasia.
Asunto(s)
Papillomaviridae , Infecciones por Papillomavirus/patología , Infecciones Tumorales por Virus/patología , Neoplasias del Cuello Uterino/patología , Biopsia , Transformación Celular Neoplásica/patología , Cuello del Útero/patología , Femenino , Humanos , Papillomaviridae/genética , Papillomaviridae/patogenicidad , Lesiones Precancerosas/patología , Factores de Riesgo , Displasia del Cuello del Útero/patología , Virulencia/genéticaRESUMEN
The clinical management of cervical carcinomas is solely based upon the FIGO-staging system. Therefore clinical staging is crucial for primary therapy of cervical carcinomas. Accurate morphologic evaluation of the surgical specimens completes the clinical staging and determines postoperative procedures and the individual prognosis. The most important morphologic prognostic factors include stromal invasion, vascular space involvement, tumor volume and surgical margins (pelvic recurrence, metastasic dissemination, survival). The prognostic and therapeutic importance of tumor biological markers is presently controversial. Radical surgical therapy (Wertheim-Meigs surgery) and primary or adjuvant pelvic radiation are currently the basic therapeutic modalities for invasive cervical carcinomas. The role of chemotherapy still needs to be defined. A less radical therapeutic approach is performed for microinvasive cervical carcinomas depending on the extent of stromal invasion, the presence of vascular space involvement and the surgical margins.
Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias del Cuello Uterino/patología , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Cuello del Útero/patología , Terapia Combinada , Femenino , Humanos , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , Radioterapia Adyuvante , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/cirugíaRESUMEN
OBJECTIVES: To compare the effect of using two region of interest (ROI) types on calculating the fractal dimensions of trabecular bone during simulated osteoporosis. METHODS: Ten 5 mm thick cross-sections from the long bone of a cow were progressively decalcified in 0.1 N Hcl for 5, 10, 20, 30, 60 and 90 min intervals, and radiographed using 0 degrees projection angle in a specially designed device. Two types of ROI (the ruggedness of the boundary and bone profiles) were placed on each digital image. Fractal dimensions and variance in mean pixel intensity were computed from each ROI using the caliper method in ImageFractal (National Institutes of Health, Washington, DC, USA). Correlation analysis quantified the relationship between changes in variance and fractal dimensions of the two types of ROI. RESULTS: A Strong correlation (r=0.90 approximately 0.98, P=0.0026) was found between variance in mean pixel intensity and decreasing fractal dimensions calculated from bone profiles. There was no consistency in the ruggedness of the boundary and increasing decalcification. CONCLUSIONS: The fractal dimensions used to characterize the ruggedness of a boundary of trabecular bone in a two-dimensional ROI are inadequate for the detection of osteoporosis, but those calculated from bone profiles may be a sensitive descriptor of trabecular bone structure.
Asunto(s)
Huesos/diagnóstico por imagen , Osteoporosis/diagnóstico por imagen , Intensificación de Imagen Radiográfica/métodos , Magnificación Radiográfica/métodos , Animales , Bovinos , Simulación por Computador , Femenino , Filtración , Fractales , Interpretación de Imagen Radiográfica Asistida por Computador/métodosRESUMEN
Telomerase activity has been found in a variety of malignant tumors but only rarely in benign tumors or normal tissues. In this study, we investigated telomerase activation in 37 ovarian tumors, including benign, borderline and malignant neoplasms. Telomerase activity was detected using the telomeric repeat amplification protocol (TRAP) in 13/16 ovarian carcinomas, 9/10 borderline tumors and 3/11 cystadenomas/fibromas. mRNA expression of the putative human telomerase catalytic sub-unit gene (hTERT) was detected by RT-PCR in 14/15 ovarian carcinomas, 8/10 borderline tumors and 4/11 cystadenomas/fibromas. In situ hybridization was performed to evaluate telomerase-RNA (hTR) expression in the corresponding paraffin-embedded tumors. Variable expression levels of hTR were found over neoplastic tumor cells. The highest levels of hTR expression were found predominantly in ovarian carcinomas. Although the amount of telomerase activity varied, significantly high levels of telomerase activity were found predominantly in ovarian carcinomas. hTERT mRNA expression was closely associated with telomerase activity. These findings suggest that up-regulation of hTERT and hTR is important for telomerase activation during malignant-tumor progression. Telomerase activation might therefore be a valuable diagnostic parameter that could help to identify potentially progressive lesions. However, the diagnostic and therapeutic implications of telomerase activation need to be clarified in clinical trials. Int. J. Cancer (Pred. Oncol.) 84:426-431, 1999.
Asunto(s)
Neoplasias Ováricas/enzimología , Neoplasias Ováricas/genética , Telomerasa/genética , Telomerasa/metabolismo , Cistoadenoma/enzimología , Cistoadenoma/genética , Femenino , Fibroma/enzimología , Fibroma/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Hibridación in Situ/métodos , Valor Predictivo de las Pruebas , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Telomerasa/química , Telómero/genética , Transcripción GenéticaRESUMEN
SILs (squamous intraepithelial lesions) comprise a wide spectrum of clinically and biologically heterogeneous lesions ranging from benign proliferations to precancerous lesions. Telomerase activation plays a critical role in cellular immortalization and might be important for malignant progression. The viral oncogenes E6 and E7 are the principal transforming genes of high-risk HPVs and are important in HPV-associated immortalization and neoplastic transformation. In this study we investigated the relationship between telomerase activity, telomerase RNA, and HPV 16/18 oncogene expression in low- and high-grade SILs and SCCs (squamous cell carcinomas) of the cervix uteri. Telomerase activity was examined by the TRAP-assay and expression of the telomerase RNA (hTR) and HPV 16/18 E6/E7 oncogenes by RNA/RNA-in situ hybridization (ISH). The associated HPV-type was determined by PCR. Telomerase activity was observed in 25/29 (86%) SCCs, 31/41 (76%) high-grade SILs, 6/14 (43%) low-grade SILs, and 1/28 (3.6%) normal cervical tissues. Expression of hTR and viral oncogenes increased significantly with histopathologic severity of the lesion (p < 0.0001). A correlation was found between telomerase activity and intensity of viral oncogene expression. These findings suggest that telomerase activation occurs early in cervical carcinogenesis and is predominantly found in high-grade SILs and cervical SCCs. Our findings support current experimental data that suggest that telomerase is at least partially activated by viral oncogenes of high-risk HPV types. Telomerase activity with concomitant strong viral oncogene expression might therefore characterize a subset of lesions that are at risk for malignant progression.
Asunto(s)
Carcinoma de Células Escamosas , ADN Viral/análisis , Papillomaviridae/genética , Telomerasa/metabolismo , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/virología , Activación Enzimática , Femenino , Expresión Génica , Humanos , Metástasis de la Neoplasia , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/enzimología , Infecciones por Papillomavirus/virología , ARN Mensajero/análisis , Telomerasa/genética , Infecciones Tumorales por Virus/diagnóstico , Infecciones Tumorales por Virus/enzimología , Infecciones Tumorales por Virus/virología , Neoplasias del Cuello Uterino/enzimología , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/enzimología , Displasia del Cuello del Útero/virologíaRESUMEN
OBJECTIVES: To compare the diagnostic accuracy for the postoperative maxillary cyst (POMC) of panoramic in combination with Waters' radiography with computed tomography (CT) and of oral and maxillofacial radiologists with non-specialists. STUDY DESIGN: Nineteen cases of POMC and 19 of postoperative changes were assessed using panoramic in combination with Waters' radiographs and CT by five oral and maxillofacial radiologists and five non-specialists on a five-point scale. The areas under the ROC curves were analysed using the Wilcoxon rank sum test to determine any differences in diagnostic accuracy between the two methods and between the two groups. RESULTS: The diagnostic accuracy of CT was higher than that of combined panoramic and Waters' radiographs for the oral and maxillofacial radiologists (P < 0.05), but not for the non-specialists (P > 0.05). The diagnostic accuracy of the oral and maxillofacial radiologists for each method was higher than that of the non-specialists group (P < 0.05). CONCLUSIONS: CT improves the evaluation of POMC. Radiological training and experience leads to more accurate diagnoses.
Asunto(s)
Quistes/diagnóstico por imagen , Seno Maxilar/diagnóstico por imagen , Enfermedades de los Senos Paranasales/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Adulto , Anciano , Medios de Contraste , Odontólogos , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Curva ROC , Radiografía Panorámica , Radiología , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos XRESUMEN
Dysregulation of cell cycle progression and telomerase activation have been implicated in malignant tumor progression as well as in the evasion of senescence and immortalization. We have investigated expression of the cell cycle control and tumor suppressor genes INK4a(p16-p14ARF), INK4b(p15-p10) and RB, and their relation to telomerase activation during malignant meningioma progression. 7/26 (27%) benign, 3/12 (25%) atypical but 4/7 (57%) anaplastic tumors lacked both, p16 and p15 protein expression. 14/39 (36%) benign and atypical but 5/7 (71%) anaplastic meningiomas contained no p14ARF mRNA. 2/46 (4%) tumors failed to express pRB. We observed frequent differential loss of expression of the alternatively spliced INK4a tumor suppressors p16 and p14ARF. Exclusive expression of the alternative INK4b transcript p10 possibly at the expense of p15 and therefore resulting in loss of p15 tumor suppressor activity was noted in two meningiomas. We have previously described telomerase activity or expression of the telomerase catalytic subunit hTERT in this meningioma series. Telomerase activation was detected in 10/27 (37%) benign, but 18/19 (95%) non-benign meningiomas. We observed no significant overall correlation between loss of INK4a/INK4b expression and telomerase activation. In conclusion, our results suggest a greater role for losses of INK4a/INK4b gene products in meningioma formation and malignant progression than previously thought. Inactivation of p16/p15- and pl4ARF-dependent pathways possibly in conjunction with telomerase activation might be critical steps for a meningioma cell towards escape from senescence, that is, immortalization.
Asunto(s)
Proteínas de Ciclo Celular/biosíntesis , Inhibidor p16 de la Quinasa Dependiente de Ciclina/biosíntesis , Genes p16 , Neoplasias Meníngeas/genética , Meningioma/genética , Proteínas de Neoplasias/metabolismo , Telomerasa/metabolismo , Proteína p14ARF Supresora de Tumor/biosíntesis , Proteínas Supresoras de Tumor , Adulto , Anciano , Anciano de 80 o más Años , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Diferenciación Celular , Senescencia Celular , Inhibidor p15 de las Quinasas Dependientes de la Ciclina , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Proteínas de Unión al ADN , Progresión de la Enfermedad , Femenino , Genes de Retinoblastoma , Genes Supresores de Tumor , Humanos , Masculino , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/patología , Meningioma/metabolismo , Meningioma/patología , Persona de Mediana Edad , Modelos Biológicos , Proteínas de Neoplasias/genética , ARN Mensajero/biosíntesis , ARN Neoplásico/biosíntesis , Proteína de Retinoblastoma/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína p14ARF Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Pigmented villonodular synovitis (PVNS) is a rare lesion of the temporomandibular joint. We report a case which was initially misdiagnosed as a parotid tumor. CT revealed a well-defined mass demonstrating higher attenuation than the adjacent soft tissue with marked expansion of the mandibular condyle. MRI clearly delineated the extent of the lesion which had very low signal intensity on both T1W and T2W sequences due to the effect of hemosiderin. The usefulness of these imaging procedures in diagnosis of PVNS is discussed.