[Determining the prognosis of spinocellular cancer of the skin and lower lip based on the TNM system and additional parameters].

Using the TNM classification established by the UICC, 427 squamous cell carcinomas of the skin and lower lip were classified as belonging to the T class. Additional histometric, histologic, and clinical tumor parameters were also recorded. Prognostic relevance was checked by comparing the overall data with those for metastatic tumors. The results showed that the overall metastasis rate was low (carcinoma of skin: 3.5%; carcinoma of lower lip: 2.7%; mean follow-up period: 5 years). Moreover, the prognoses based on the tumor diameter classes in the TNM system were not specific. Earlier findings tend to indicate that tumor thickness, depth of infiltration, and grade of malignancy should also be taken into consideration if the prognosis is to be estimated accurately. If the level and tumor thickness are taken into consideration, a large group of tumors (50%) can be separated: these tumors do not metastasize, even though they are at least 2 mm thick, and they do not infiltrate the subcutaneous tissue (no risk group).