Metastatic basal cell carcinoma: review, pathogenesis, and report of two cases.

In 93 reported cases of metastatic basal cell carcinoma (BCC), 76 had spread through lymphatics or blood vessels. Two more cases are presented, bringing the total to 78. Metastasis to regional lymph nodes was the most frequent, followed in frequency by lungs, bones, and other organs. The size of the primary tumor, its site, its resistance to x-ray therapy, and the effects of radiation appeared to contribute to the occurrence of metastasis. However, in an appreciable number of cases, tumor dissemination was related to incomplete excision followed by immediate wound closure, particularly by grafting. It is recommended that wound grafting be delayed for at least six months after excision or large or recurrent BCC in order to assure complete removal.