Squamous carcinoma of the lower lip in patients under 40 years of age.

In a series of 1,308 squamous carcinomas of the lower lip, 97 (7%) occurred in patients under 40. Among the 56 followed up for at least five years, there were 12 deaths due to disease for a determinate mortality of 21%. In five of these patients (41%) the tumor persisted more than three years from the time of initial treatment and in four others (33%), for more than five years. Of all 97 patients, 15 (15%) developed additional primary tumors. Most second lesions were squamous or basal cell carcinomas of the skin; however, four patients developed second primary lesions with considerable malignant potential (one melanoma and three visceral cancers). Three of these patients died of their second tumors, raising the overall mortality to 26%. Squamous carcinoma of the lower lip appears to have a worse prognosis in younger patients. A significant fraction of these patients succumb to their disease more than five years after initial treatment. This, coupled with a tendency to develop significant second primaries, suggests that a protracted period of close clinical follow-up is essential.