Читать книгу Anterior Skull Base Tumors - Группа авторов - Страница 46

Synovial sarcoma may involve the skull base region as extension from oropharynx or adjacent structures [67]. The tumour affects young patients with a median of 25 years and a male predominance. A specific chromosomal translocation t(X;18)(p11;q11) that leads to the formation of the SS18-SSX fusion gene has been described in a subset of patients [68–70]. Histologically, synovial sarcoma may present as a pure spindle cell variant (monophasic) or biphasic when both spindle and epithelial components are present. The epithelioid component is typically formed of cuboidal or columnar epithelial cells forming cords, nests, and pseudoglandular spaces intermingled with a spindle cell proliferation. Although morphology is the cornerstone for diagnosis, ancillary markers, including keratin and epithelial membrane markers, can be used. In situ or PCR-based hybridisation for the t(X;18)(p11.2; q11;2) translocations may be of help, if positive [71, 72].