The syndrome of perifollicular fibromas and colonic polyps was delineated 20 years ago by Hornstein and Knickenberg; it probably occurs more frequently than suggested by the literature. Multiple perifollicular fibromas were found in a mother and daughter. The mother also had colonic polyps. This dermo-intestinal syndrome varies in its clinical manifestations, but it is probably an autosomal dominant trait. We believe that the Horn-stein-Knickenberg syndrome and the Birt-Hogg-Dubé syndrome are identical. If perifollicular fibromas are observed and cannot be explained as postinflammatory sequelae of acne, the patient should be examined for colonic polyps as an appropriate from of cancer screening.