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What is Basal cell carcinoma usually spreads by which route: September 2007 and explain in detail?
Ans. C: Direct spread Basal cell carcinoma is the most common malignancy in Caucasian individuals. Despite this high incidence, metastatic basal cell carcinoma is extremely rare. The primary mode of spread of basal cell carcinoma is by direct extension. Nearly 85% of all metastasizing basal cell carcinomas involve the head and neck region. Metastatic spread is most often to the regional lymph nodes followed in descending order by the lungs, bones, and skin. Risk factors for metastatic basal cell carcinoma include persistent tumor for many years, previous radiation and large tumor size.