This case–control cohort study by the experienced researchers and doctors included a total of 131 non‐small‐cell lung cancer patients. The prevention group comprised 40 patients treated with topical betaxolol 0.25% solution to prevent paronychia while receiving EGFR‐TKI therapy. High rates of posttreatment discomfort, infection, recurrence, and increased time to return to work have been noted after nail plate avulsion resulting from epidermal growth factor receptor tyrosine kinase inhibitor EGFR‐TKI induced paronychia, which may even interrupt the course of treatment for EGFR‐TKI therapy. Thus, the researchers conducted this study to determine how effectively a topical β‐blocker, betaxolol, prevents EGFR‐TKI‐induced paronychia. The control group comprised 91 patients who did not preventively use topical betaxolol 0.25% solution while receiving EGFR‐TKI therapy. The patients’ age, gender, antineoplastic regimen, duration of antineoplastic treatment before the appearance of lesions, number of involved digits (fingernails or toenails) with lesions, grading of paronychia, and pain score were recorded.

Regarding the cumulative incidence of paronychia, the researchers noted some significant differences at both the 2nd and 3rd months after starting EGFR‐TKIs. Furthermore, the average visual analog scale scores were 3.125 and 6.29 in the prevention and control groups. The average grades of paronychia were 1.5 and 2.12 in the prevention and control groups, respectively. The average numbers of involved digits were 2.25 in the prevention group and 3.03 in the control group.