Hornstein-Knickenberg syndrome vs. Birt-Hogg-Dubé syndrome: a critical review of an unjustified designation.

Abstract

The disorder that is presently called 'Birt-Hogg-Dubé syndrome' was in reality delineated in 1975 by Otto P. Hornstein and Monika Knickenberg from Erlangen (Germany) who emphasized that the occurrence of multiple 'perifollicular fibromas' represented a distinct autosomal dominant trait heralding extracutaneous cancer proneness. By contrast, Arthur R. Birt, Georgina R. Hogg and W. James Dubé from Winnipeg, Manitoba, Canada, claimed in 1977 that they had discovered 'a previously unrecognized hereditary pilar hamartoma' for which they proposed the name 'fibrofolliculoma', to be distinguished from the perifollicular fibromas as reported by Hornstein and Knickenberg. Today, many authors believe that 'fibrofolliculoma' is identical with 'perifollicular fibroma', but for the purpose of the present article this question can be left open. More importantly, the Canadian authors did not mention any association with extracutaneous cancer proneness within the large family examined in Winnipeg, nor when discussing the report from Erlangen, which means that they have neither described nor redescribed the syndrome that presently bears their names. Hence, the autosomal dominant disorder of multiple perifollicular fibromas heralding proclivity to extracutaneous cancer should be called after the original authors, Hornstein-Knickenberg syndrome.