Abstract
Reports were made on the 2 cases of Naevus comedonicus, an atypical one observed on the upper half of the body of a male patient aged 72 and the other a typical one observed on the left side of the neck of a male patient aged 32.
Varying names have been given denoting the disease under discussion, but the authors recommend to call it as Naevus comedonicus. Histologically, the follicles of hair were found to have markedly opened and contained keratic thrombus. In the former case, cord-like epithelial proliferation was recognized from the follicular wall towards the corium together with a number of naevus cell like cells. The sebaceous gland was found to be either absent or atrophied. In the latter case, cornification of the excretory duct of sebum was remarkable and the sebaceous gland was found to have markedly swollen. It is considered, therefore, that the cornification of the excretory duct of sebum is playing an important role in the development of Naevus comedonicus.
