Bioimpact of EGFR antagonists on the pilosebaceous follicles

Area of Science:

• Dermatology
• Oncology
• Bioinstrumentation

Background:

• Targeted cancer therapies, particularly epidermal growth factor receptor (EGFR) inhibitors, frequently cause skin adverse events.
• Previously, these skin changes were broadly categorized as a rash, lacking specific characterization.

Purpose of the Study:

• To objectively assess early structural and functional skin changes induced by EGFR inhibitor treatment using non-invasive bioinstrumentation.
• To identify specific skin alterations associated with EGFR inhibitor therapy beyond generalized rash.

Main Methods:

• A cohort of 27 cancer patients (aged 58-66 years) undergoing EGFR inhibitor treatment were evaluated.
• Non-invasive bioinstrumentation, including Visioscan® and Visiopor® ultraviolet light emitting CCD cameras, was used for assessments.
• Forehead skin was assessed weekly for up to 2 months, with no topical treatments applied.

Main Results:

• Visioscan® imaging revealed specular light reflectance indicative of follicular plugging and occasional focal hyperkeratosis in the interfollicular stratum corneum.
• These observed skin changes, particularly follicular plugging and hyperkeratosis, increased in severity with continued EGFR inhibitor treatment.
• Visiopor® imaging showed no significant changes in follicular fluorescence throughout the treatment period.

Conclusions:

• The study suggests that EGFR inhibitor treatment leads to follicular hyperkeratosis, a condition termed EGFR inhibitor-induced kerosis.
• This induced kerosis, characterized by follicular plugging, is proposed as a potential cause of acneiform reactions observed in patients.
• Non-invasive bioinstrumentation provides objective data for characterizing early-onset skin adverse events in targeted cancer therapy.