Symptomatic Relief of Skin Toxicities Induced by EGFR TKI Therapy: Use of Bicarbonate Ion Bath Salts

Abstract

Introduction: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy for non–small cell lung cancer with EGFR gene mutation is associated with a high occurrence of skin disorders, such as dermatitis, dry skin, and paronychia. Moisturizers, steroids, and oral minocycline are used to treat these adverse effects, with limited efficacy. We conducted a pilot study to investigate the usefulness of bicarbonate ion bath salts, which are known to have excellent moisturizing properties, for treating skin disorders caused by EGFR TKI therapy.

Methods: Four female patients (aged 51-73 years) with EGFR mutation–positive lung adenocarcinoma bathed with bicarbonate ion bath salts for 10 minutes once daily as treatment for cutaneous symptoms. Patients were instructed to record values on a visual analog scale to rate dry skin and pruritis for 2 weeks before using the salts (observation phase), during 4 weeks of bathing with the salts (intervention phase), and for 2 weeks after terminating the intervention (washout phase).

Results: All four patients showed significant improvement in dry skin and pruritis during the intervention phase. One patient had a mild re-exacerbation of symptoms during the late intervention phase. During the washout phase as compared to the intervention phase, two patients experienced significantly worsened dryness of the skin, and one patient had worsened pruritis. All patients maintained significant improvement during the washout phase compared to the observation phase.

Conclusions: Bicarbonate ion bath salts may be an effective treatment for EGFR TKI–induced dry skin and pruritis.