The study reports the first case of basaloid squamous cell carcinoma (
BSCC) involving both the oral mucosa and the tuberosity area of the ma
xilla. The tumour showed many histological similarities to cases previ
ously reported, though mitoses were not frequent. The immunoreactivity
for cytokeratin, S-100, vimentin, Ki-67, p53, c-erbB-2 and bcl-2 was
also investigated. Immunostaining for the bcl-2 protein showed a high
extent of positive cells, although only a moderate staining intensity.
Staining for c-erbB-2 was negative. The pathological findings and the
immunoreactivity may indicate that BSCC is not as high a grade carcin
oma as previously suggested. Additional studies are thus clearly neede
d to confirm or reject this impression. (C) 1997 Elsevier Science Ltd.