Invasive cutaneous squamous cell carcinoma associated with actinic keratosis - A case with orbital invasion and meningeal infiltration

BACKGROUND. It is suggested that most squamous cell carcinomas in sun-expos ed areas arise from preexisting solar keratosis. Actinic keratosis is thoug ht of as being a precursor to squamous cell carcinoma. This form of squamou s cell carcinoma has been considered to be a relatively benign lesion. We r eport a case of invasive squamous cell carcinoma associated with actinic ke ratosis leading to orbit destruction and meningeal infiltration. OBJECTIVE. TO demonstrate that well-differentiated tumors can act extremely aggressively with the potential toward infiltrative growth patterns. METHODS. Histologically controlled surgery along with multiple radiation th erapy was performed. RESULTS. The tumor progressed inducing perineural invasion, orbit infiltrat ion, osseous destruction, and meningeal invasion. CONCLUSION. The association of squamous cell carcinoma and actinic keratosi s supports the concept of a causal relation. Excision with histologic exami nation of actinic keratosis seems to be useful for accurate diagnosis. Squa mous cell carcinoma can represent an aggressive tumor with infiltrative gro wth pattern and should not be considered a benign lesion.