Risk stratification for metastasis from cutaneous squamous cell carcinoma of the head and neck

The purpose of the study was to develop a system of risk stratification, based on clinical and histological factors that would aid prediction of metastasis from cutaneous squamous cell carcinoma (SCC) of the head and neck.

The method used was a retrospective case control study comparing clinical and histological parameters of 78 patients who developed metastasis with 92 patients who did not develop metastasis over a 5-year period.

The two 'absolute' (highest) risk factors for development of metastatic disease are poor histological differentiation and perineural/lymphovascular infiltration. The three 'relative' risk factors are moderate histological differentiation, diameter ≥20 mm and Clark level 5.

High-risk lesions have either one of the absolute risk factors or all three of the relative risk factors with a predicted incidence of metastasis of 37%. Intermediate risk lesions have two of three relative risk factors and a predicted incidence of metastasis of 5%. Low-risk lesions have one or none of the relative risk factors and a predicted incidence of metastasis of 0.3%.

Ongoing management of patients with histo-pathologically proven invasive SCC of the head and neck should be based upon risk stratification for metastasis.