Περίληψη:
On the basis of the heterogeneity of cytokeratins 7 and 20 expression in
malignant epithelial tumors, the cytokeratin 7/20 immunophenotype has
served as a useful diagnostic tool for discrimination of primary and/or
metastatic carcinomas of unknown origin. However, the expression pattern
of these cytokeratins in malignant salivary gland tumors has not been
thoroughly studied. Our study material was composed of 84 malignant
tumors of primary major or minor salivary gland origin. Nine histologic
types of carcinoma were represented, including mucoepidermoid (26
cases), adenoid cystic (25), polymorphous low grade (11), salivary duct
(8), acinic cell (4), ex mixed tumor (3), not otherwise specified (3),
clear cell (2), and basal cell (2). In all, 13 cases of primary skin or
mucosal squamous cell carcinoma with secondary salivary gland
involvement were also examined. Immunoreactivity for cytokeratin 7 was
evident in all malignant salivary gland tumors; the staining pattern was
diffuse and strong in 62 cases, and focal and strong in 22 cases. In
contrast, 78 cases were negative for cytokeratin 20, whereas only six
cases (two mucoepidermoid, one adenoid cystic, and three salivary duct)
displayed focal weak positivity. Overall, 92.9% of malignant salivary
gland tumors were characterized by a cytokeratin 7 positive / 20
negative immunoprofile, the remaining 7.1% of cases being positive for
both cytokeratins. The latter phenotype was more common in salivary duct
carcinomas (Pless than or equal to0.05). On the other hand, most
squamous cell carcinomas (69%) were negative for both cytokeratins,
while the remaining cases (31%) were negative for cytokeratin 20 and
focally weakly positive for cytokeratin 7. We suggest that assessment of
cytokeratin 7/20 immunoprofile may facilitate the differential diagnosis
of (a) primary malignant salivary gland tumors from metastatic tumors,
(b) metastatic salivary gland tumors, (c) primary salivary gland tumors,
especially mucoepidermoid carcinomas, from squamous cell carcinomas, and
(d) salivary duct carcinomas from other malignant salivary gland tumors.
Συγγραφείς:
Nikitakis, NG
Tosios, KI
Papanikolaou, VS
Rivera, H and
Papanicolaou, SI
Ioffe, OB
