title: Molecular genetic analysis excludes implantation metastasis of basal cell carcinomas.
abstract: Basal cell carcinoma (BCC) of the skin is the most common tumor in the white population. A 66-year-old man developed 2 BCCs at the left parietal region of the head and at the helix of the left ear. The 2 lesions matched exactly when pressing the ear against the head, suggesting an implantation metastasis mechanism. Molecular genetic techniques were used to confirm or exclude such a mechanism in this rare clinical constellation. Tumor tissues were precisely microdissected for DNA isolation. Exons 5-9 of the p53 tumor suppressor gene were directly sequenced. In addition, loss of heterozygosity analysis of chromosome 9q was performed using 5 polymorphic microsatellite markers. The BCC of the ear revealed a p53 mutation at codon 273, whereas the other one lacked this mutation. In addition, the smaller BCC of the ear showed loss of heterozygosity at 9q33.3, in contrast with the larger BCC. Interestingly, histologically normal skin of the ear distant from the small BCC had the same deletion, indicating a field defect of this skin patch at 9q33.3. Molecular genetic analysis clearly demonstrated different genetic alterations of the two BCCs and therefore most likely excludes a mechanism of implantation metastasis.
authors.affiliation: Department of Dermatology, University of Regensburg, 93042 Regensburg, Germany. christian.hafner@klinik.uni-regensburg.de
authors.forename: Christian
authors.initials: C
authors.lastname: Hafner
authors.forename: Arndt
authors.initials: A
authors.lastname: Hartmann
authors.forename: Ruth
authors.initials: R
authors.lastname: Knuechel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dietmaier
authors.forename: Michael
authors.initials: M
authors.lastname: Landthaler
authors.forename: Thomas
authors.initials: T
authors.lastname: Vogt
mesh_terms: D000368:Aged; D002280:Basal Cell Carcinoma / Q000235:genetics / Q000473:pathology*; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000737:chemistry / Q000235:genetics*; D003937:Diagnosis, Differential; D004423:Ear; D006257:Head; D006801:Humans; D019656:Loss of Heterozygosity; D008297:Male; D009154:Mutation; D009366:Neoplasm Seeding; D016609:Neoplasms, Second Primary / Q000235:genetics / Q000473:pathology; D016133:Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000235:genetics / Q000473:pathology*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics
chemical_list: D004273:DNA, Neoplasm; D016159:Tumor Suppressor Protein p53