Differential expression of epidermal growth factor receptor in various pathological types of salivary gland cancers

Area of Science:

• Oncology
• Molecular Biology

Background:

• Epidermal growth factor receptor (EGFR) expression is reported in salivary gland cancer (SGC), but definitions of positivity vary.
• This variability hinders consistent interpretation and application of EGFR status in SGC.

Purpose of the Study:

• To assess EGFR expression levels in SGC using both EGFR positive score and cumulative EGFR score.
• To analyze variations in EGFR expression across different SGC histological subtypes.

Main Methods:

• Retrospective review of 102 SGC patients who underwent surgical resection (January 2010 - April 2021).
• Immunohistochemistry was used to evaluate membrane staining intensity (0-3+).
• Cumulative EGFR score calculated using a formula incorporating staining intensity and percentage of positive cells (0-300 scale).

Main Results:

• EGFR expression showed wide variation in SGC, both within and between histological types.
• Average EGFR positive scores ranged from 1.0% (AcCC) to 76.8% (SqCC).
• Average cumulative EGFR scores ranged from 1 (AcCC) to 185 (SqCC).

Conclusions:

• EGFR positive and cumulative scores in SGC differ significantly across histological types.
• These quantitative EGFR scores may serve as predictors for SGC patient outcomes with EGFR-targeted therapies.
• Further studies are warranted to validate the predictive value of these EGFR scores in clinical settings.