Hair Follicle Tumors

Abstract

The bewildering variety of hair follicle proliferations and tumors is demonstrated by the complex terminology used to describe them. Hair follicle tumors were originally described and named during the late 19th century. Little more was accomplished until the last 25 years, when newer knowledge of the hair cycle and structure made biochemical and ultrastructural studies of such tumors possible (Duperrat and Mascaro 1965, Pinkus and Mehregan 1969, Headington 1976, Pinkus 1978). The second effort at studies of hair tumors produced not only new insight into their bipgenesis but also a new group of names so that now most tumors have new, as well as old, names, and sometimes more than one of each (Table 1).