RESUMO
BACKGROUND: Synovial sarcoma, a rare tumor in the head and neck, has been historically diagnosed by its characteristic biphasic histologic pattern. Monophasic variants exist which can be difficult to diagnose. METHODS: Two cases of synovial sarcoma of the head and neck are presented. Both cases, cytogenetic analysis was performed using standard protocols. RESULTS: Both tumors demonstrated a chromosomal translocation, t(X;18)(p11.2;q11.2), which either made or confirmed the diagnosis. CONCLUSIONS: Synovial sarcoma contains a characteristic chromosomal translocation which is a useful diagnostic tool, especially when histologic studies are equivocal.
Assuntos
Cromossomos Humanos Par 18/genética , Neoplasias de Cabeça e Pescoço/genética , Sarcoma Sinovial/genética , Translocação Genética/genética , Cromossomo X/genética , Adulto , Idoso , Diagnóstico Diferencial , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Leiomiossarcoma/diagnóstico , Masculino , Neoplasias Parotídeas/diagnóstico , Neoplasias Parotídeas/genética , Neoplasias Parotídeas/patologia , Neoplasias Faríngeas/diagnóstico , Neoplasias Faríngeas/genética , Neoplasias Faríngeas/patologia , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/patologia , Neoplasias Cranianas/diagnóstico , Neoplasias Cranianas/genética , Neoplasias Cranianas/patologiaRESUMO
The mdx mouse has a mutated dystrophin gene and is used as a model for the study of Duchenne muscular dystrophy (DMD). We investigated whether regenerating mdx skeletal muscle contains the extracellular matrix protein tenascin-C (TN-C), which is expressed in wound healing and nerve regeneration. Prior to the initiation of muscle degeneration, both normal and mdx mice displayed similar weak staining for TN-C in skeletal muscle, but by 3 weeks of age the mice differed substantially. TN-C was undetectable in normal muscle except at the myotendinous junction, while in dystrophic muscle, TN-C was prominent in degenerating/regenerating areas, but absent from undegenerated muscle. With increasing age, TN-C staining declined around stable regenerated mdx myofibers. TN-C was also observed in muscle from dogs with muscular dystrophy and in human boys with DMD. Therefore, in dystrophic muscle, TN-C expression may be stimulated by the degenerative process and remain upregulated unless the tissue undergoes successful regeneration.
