EGFR expression and copy number changes in low T‐stage oral squamous cell carcinomas

Abstract

Only a small subgroup of early oral SCC is characterized by EGFR amplification, which can be identified reliably using EGFR-SISH technology. This finding suggests that EGFR gene amplification mostly occurs in advanced stages of oral SCC.

Changes in Epidermal Growth Factor Receptor Gene Copy Number during Oral Carcinogenesis

“…This is consistent with data from studies of EGFR GCN in OSCC, which indicate that EGFR genomic gain is a late event in oral carcinogenesis (23)(24)(25). It is striking, however, that the majority of OPMD with low polysomy progressed to OSCC.…”

“…This finding was consistent across both the early-stage and transformed OSCC groups. It is higher than the 9% rate reported in a tissue-microarray study by R€ ossle and colleagues (24). This earlier study also focused on early-stage (stage I/II) OSCC; however, it was limited by assessment of 0.6 mm diameter tissue cores.…”

“…The prevalence of EGFR genomic gain in OSCC ranges from 9% to 56% (23)(24)(25)(26) and is more frequent in stage III/IV disease, suggesting that EGFR genomic gain is a late event in oral carcinogenesis. By contrast, data from two OPMD studies show that cases with low polysomy are more likely to progress to OSCC (27,28).…”

Difference in EGFR expression and mean vascular density in normal oral mucosa, oral epithelial dysplasia and oral squamous cell carcinoma.

“…Regarding evaluation of EGFR, authors such as Rössle et al 6 and Rajesweri et al 28 and the authors of this study found that in all the samples analyzed, regardless of diagnosis, immunostaining of EGFR was always positive. However, there were variations in its intensity range.…”

“…5 Its mutation stimulates mitosis and inhibits the apoptosis of neoplastic keratinocytes. 6 This receptor is expressed both in normal epithelia and in those subjects with pathologies such as epithelial dysplasia and carcinomas, where proliferation and differentiation of keratinocytes are altered.…”