Influence of embryonal fusion lines for recurrence of basal cell carcinomas in the head and neck.

A reinvestigation of 171 basal cell carcinomas of the head and neck treated by surgical excision revealed 23 recurrences. Recurrence rate in one group of basal cell carcinomas, situated on embryologic fusion lines, was statistically higher than in other groups of basal cell carcinomas situated on other parts of the face and on the capillitium which served as control. Histopathologic subclassification of the recurrent basal cell carcinomas revealed a higher incidence of nodular type with infiltrative margin and of the infiltrative type. Basal cell carcinomas situated in fusion lines tended to grow deeper than in other sites. It was concluded that embryologic fusion lines in the face provide risk zones for spread and recurrence of basal cell carcinomas. Subclassification of basal cell carcinomas should be performed in the routine histopathologic reporting of these neoplasms as a means of predicting recurrence.