Chemotherapy for squamous cell carcinoma of the lip

Abstract

Lip cancer is a rare type of oral cancer, mostly comprised of squamous cell carcinoma but can also include basal cell carcinoma, adenocarcinoma, and mucoepidermoid carcinoma of salivary glands. It accounts for approximately 25 % of all oral cavity cancers. Cancers of the lip occur 3–13 times more frequently in fair-skinned males over 50 years old, likely secondary to both occupational sun exposure and greater tobacco and alcohol use. The incidence of locoregional spread and lymph node spread depends on the location, size, grade, and overall stage at the time of diagnosis. Overall, the early stages of disease have <10 % incidence of lymph node spread. Due in part to their easily visible location, lip cancers are frequently detected and treated early. However, approximately 10–15 % patients have systemic metastatic disease at the time of diagnosis. The majority of lip cancers occur in the lower lip as was shown in one 25-year retrospective study of over 2,000 patients. Up to 95 % of the cancers of the lower lip are squamous cell carcinomas (SCC). The upper lip and commissures are also most frequently SCC and have a worse prognosis with faster growth rates and ulceration. Additionally, the lymphatic system of the upper lip is distinct and more extensive than the lower lip. Therefore, SCC of the upper lip are more likely to invade the nasal cavity and premaxilla via the deep superior jugular nodes and require more aggressive treatment. Embryologic fusion in the midline prevents contralateral spread in the SCC of the upper lip. However, for SCC of the lower lip, evaluation of both the ipsilateral and contralateral lymph nodes (levels I–III) needs to be completed. In addition, the specific location of the tumor on the lip itself also affects its course. A midline primary cancer has an increased risk for contralateral lymph node disease and therefore warrants a bilateral neck evaluation.