Multiple primary tumours in oral cancer.

In 210 cases of oral cancer, 38 (17.6%) second primary tumours were found. Males had a higher chance of developing a second primary than females (21.4% versus 12%). The difference was not statistically significant (p = 0.11). When the index tumour was in the lower part of the oral cavity (floor of mouth, retromolar trigone, inferior alveolar process), a higher rate of second primaries was found than in cancer of the rest of the oral cavity (tongue, buccal mucosa and palate) (26.6% versus 11.5%). In male patients, this difference was statistically significant (p less than 0.05). 4 tumours were synchronous. In those 4 patients, panendoscopy would not have contributed to an earlier diagnosis. Routine panendoscopy in oral cancer therefore seems not valid.