THE ABSENCE OF HARVEY RAS MUTATIONS DURING DEVELOPMENT AND PROGRESSION OF SQUAMOUS-CELL CARCINOMAS OF THE HEAD AND NECK

We have examined the incidence of Harvey ras mutations in human squamo us cell carcinomas (SCC) of the upper aerodigestive tract using the po lymerase chain reaction (PCR) followed by direct sequencing. No mutati ons were detected at codons 12, 13, 59 or 61 of this gene in any of si x papillomas, five erythroplakias, 56 squamous cell carcinomas, and 16 SCC cell lines. Some of the SCC were lymph node metastases (three) or tumours which had recurred following radiotherapy (seven). We conclud e that Harvey ras mutations are not a common event in the pathogenesis or recurrence of SCCs from Caucasian subjects, in contrast to the sit uation with Indian populations (Saranath et al., 1991).