RESUMO
Solitary fibrous tumor (SFT) is an uncommon mesenchymal neoplasm that usually arises in the pleura. Although this tumor has been described in other sites, including the head and neck area, in the oropharynx it is extremely rare. We report the first case of a SFT arising from the palatine tonsil of a 62-year-old man. The tumor consisted of spindle-shaped cells distributed in a haphazard pattern and presented atypical histological features such as hypercellular areas and high mitotic count. Immunohistochemical studies showed strong positivity for CD34 and bcl-2, and weak positivity for desmin. Smooth muscle actin, S-100 protein and cytokeratines were negative. The patient was well without disease 1 year after surgery.
Assuntos
Fibroma/patologia , Tonsila Palatina/patologia , Neoplasias Tonsilares/patologia , Antígeno 12E7 , Antígenos CD/análise , Antígenos CD34/análise , Moléculas de Adesão Celular/análise , Diagnóstico Diferencial , Fibroma/química , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Tonsila Palatina/química , Neoplasias Tonsilares/química , Resultado do Tratamento , Proteína X Associada a bcl-2/análiseRESUMO
OBJECTIVE: Human herpesvirus 8 (HHV-8) and Epstein-Barr virus (EBV) are human pathogens associated to a number of neoplasms, including tumors of the Waldeyer's ring. Both viruses have been previously detected by in situ methods in tonsils and adenoids from children. HHV-8 was found in 6.8% of the cases and EBV in about one third of the cases. As they belong to the same gamma-herpesvirus subfamily and share some biological characteristics, it is of medical interest to further explore their possible relationship in the Waldeyer's ring, an issue not yet addressed in the specialized literature. The purpose of the present study is to compare the presence of EBV by in situ hybridization (ISH) in tonsils and adenoids from children up to 14 years of age in cases previously shown to be positive and negative for HHV-8. METHODS: Paraffin wax-embedded sections consisting of 38 tonsils and two adenoids from 40 patients were analyzed. HHV-8 was detected by ISH, using the T1-1 probe for the viral mRNA. EBV was also detected by ISH, using the EBER probe. Both probes and the detection systems were provided by Novocastra. RESULTS: HHV-8 was detected in 19 tonsils and one adenoid. The other 19 tonsils and one adenoid taken from the HHV-8-negative group were selected by pairing age and gender of patients with the HHV-8-positive group. In both groups EBV was detected in 13 cases and was negative in other 7. CONCLUSION: Although both viruses are related in many aspects, some biological and epidemiological features differ. This is reflected in the present results, as EBV is similarly detected in the groups negative and positive for HHV-8, favoring different mechanisms of spread.
Assuntos
Tonsila Faríngea/virologia , Herpesvirus Humano 4/isolamento & purificação , Herpesvirus Humano 8/isolamento & purificação , Tonsila Palatina/virologia , Tonsila Faríngea/química , Adolescente , Criança , Pré-Escolar , DNA Viral/análise , Feminino , Humanos , Hibridização In Situ , Lactente , Masculino , Tonsila Palatina/química , Inclusão em ParafinaRESUMO
OBJECTIVE: To assess whether foot-and-mouth disease virus (FMDV)-specific sequences could be identified in tissues from persistently virus-infected animals. DESIGN: Cattle with experimentally induced persistent FMDV infections were slaughtered at 750 days after viral exposure. Experimentally infected pigs were slaughtered at 28 days after FMDV inoculation. Postmortem specimens were asceptically removed. ANIMALS: Three bovids and 3 pigs were studied, as well as 1 control animal for each species. PROCEDURE: Various tissues were examined for the presence of FMDV-specific sequences by dot-blot hybridization assay, using a molecularly cloned FMDV cDNA corresponding to the polymerase coding region. RESULTS: The FMDV-specific genomic sequences were only detected in RNA from spleen, lung, larynx, tonsils, pancreas, liver, esophagus, and WBC of bovids. CONCLUSIONS: It was established that, at late stages of the persistent infection, when virus isolation was not possible, cattle may carry FMDV-specific sequences in different tissues. Retention of viral sequences could not be demonstrated in specimens from experimentally infected swine, 28 days after viral inoculation.