EGFR and MYC gene copy number aberrations are more common in squamous cell carcinoma than keratoacanthoma: a FISH study

• Published in: Journal of cutaneous pathology Vol. 40; no. 5; pp. 447 - 454
• Main Authors: Jacobs, Melissa S., Persons, Diane L., Fraga, Garth R.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.05.2013
• Subjects: Aged; Biomarkers, Tumor - genetics; Biomarkers, Tumor - metabolism; Carcinoma, Squamous Cell - genetics; Carcinoma, Squamous Cell - metabolism; Carcinoma, Squamous Cell - pathology; DNA, Neoplasm - genetics; epidermal growth factor receptor; fluorescence in-situ hybridization; Gene Amplification; Gene Dosage; Genes, erbB-1 - genetics; Genes, myc - genetics; Genetic Markers - genetics; Humans; In Situ Hybridization, Fluorescence - methods; keratoacanthoma; Keratoacanthoma - genetics; Keratoacanthoma - metabolism; Keratoacanthoma - pathology; Middle Aged; MYC; Observer Variation; Reproducibility of Results; Skin Neoplasms - genetics; Skin Neoplasms - metabolism; Skin Neoplasms - pathology; squamous cell carcinoma; Warts - genetics; Warts - pathology
• ISSN: 0303-6987; 1600-0560
• DOI: 10.1111/cup.12117

Epidermal growth factor receptor (EGFR) and MYC genomic aberrations have been described in cutaneous squamous cell carcinoma (SCC) but have not been widely investigated in keratoacanthoma (KA). EGFR and MYC were evaluated by fluorescence in situ hybridization and immunohistochemistry in 8 verrucae, 19 involuting KA (IKA), 23 classic KA (CKA), 6 atypical KA (AKA) and 19 SCC. Increased EGFR gene copy number was seen in 9 of 23 CKA and 14 of 19 SCC (p = 0.03). Increased MYC gene copy number was observed in 7 of 23 CKA and 17 of 19 SCC (p = 0.0001). MYC gene amplification was more common in SCC than CKA (p = 0.005), while EGFR gene amplification was rare and not significant. MYC protein overexpression was identified in 6 of 23 CKA and 14 of 19 SCC (p = 0.005). There was no statistical difference in EGFR protein overexpression in SCC and CKA (p = 0.06). EGFR and MYC aberrations were rare in IKA. AKA showed EGFR and MYC anomalies at an incidence intermediate between CKA and SCC. EGFR and MYC gene copy number aberrations are more common in SCC than KA. The incidence of aberrations parallels the degree of cytologic atypia in KA.