title: Multiple familial basal cell carcinomas including a case of segmental manifestation.
abstract: BACKGROUND
  A tendency to develop multiple basal cell carcinomas at an early age is a characteristic feature of some rare hereditary disorders; moreover, multiple basal cell carcinomas are sometimes observed as a corollary of familial basaloid follicular hamartomas or familial multiple trichoepitheliomas.
  
  
  METHODS
  We report 3 cases of multiple basal cell carcinomas involving 3 successive generations of a family, with a segmental manifestation of lesions in one of these patients. No additional cutaneous or extracutaneous anomalies were found.
  
  
  CONCLUSIONS
  We hypothesize that a gene mutation may have caused the tumors observed in this family as an autosomal dominant trait. The segmental arrangement of tumors may reflect loss of heterozygosity: at an early stage of embryogenesis, a postzygotic mutation would give rise to a population of cells either homozygous or hemizygous for the underlying gene. The segmental arrangement following the lines of Blaschko would visualize the dorsoventral proliferation of a cell clone characterized by loss of the corresponding normal allele.
authors.affiliation: Institute of Dermatology, University of Messina, Italy. Bagio.Guarneri@unime.it
authors.forename: B
authors.initials: B
authors.lastname: Guarneri
authors.forename: F
authors.initials: F
authors.lastname: Borgia
authors.forename: S P
authors.initials: SP
authors.lastname: Cannavò
authors.forename: M
authors.initials: M
authors.lastname: Vaccaro
authors.forename: R
authors.initials: R
authors.lastname: Happle
mesh_terms: D000328:Adult; D000368:Aged; D002280:Basal Cell Carcinoma / Q000235:genetics / Q000473:pathology*; D002648:Child; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D010375:Pedigree; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000235:genetics / Q000473:pathology*