Cytokeratin alterations as diagnostic and prognostic markers of oral and pharyngeal carcinomas. A prospective study.

Cytokeratin (CK) alterations have been reported in carcinomas from differen t anatomical sites, and these have been associated with specific aspects of tumour behaviour. In order to assess the relationships between CK modifica tions and future tumour behaviour, we conducted the present prospective stu dy on 26 squamous cell carcinomas (SCC) of oral and pharyngeal mucosae and corresponding controls. Cytokeratins were investigated using two-dimensiona l gel electrophoresis and immunofluorescence techniques. All healthy tissue s, oral lining and oropharyngeal mucosae, expressed the oesophageal type CK s, including CK 19. Other simple epithelial CKs (7, 8, 17 and 18) were not detected. In carcinomas originating from corresponding sites, expression of oesophageal CKs varied widely from one specimen to another, and simple epi thelial keratins were often found. Statistical analysis indicated correlati ons between CK expression and the clinicopathological data of SCC patients. Small tumour size was strongly associated with the expression of CKs 10 an d 19. interestingly, an absence of lymph node involvement was significantly associated with CK 18 expression. Tumours giving rise to recurrences, meta chronous tumours, and distant metastasis were significantly associated with an absence of CK 13. These results suggest that CKs 10, 19, 18 and 13 coul d be reliable diagnostic and prognostic markers in the assessment of oral a nd pharyngeal squamous carcinomas.