Zinc deficiency associated with cutaneous toxicities induced by epidermal growth factor receptor tyrosine kinase inhibitor therapy in patients with lung adenocarcinoma.

PURPOSE: Cutaneous toxicities are common adverse effects following epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) therapy. Zinc deficiency causes diverse diseases, including skin toxicities. Therefore, this study aimed to investigate the role of zinc deficiency in patients with EGFR-TKI-induced skin toxicities. EXPERIMENTAL DESIGN: This retrospective study enrolled 269 patients with diverse skin disorders who visited our hospital between January 2016 and December 2017. The skin toxicity severities and plasma zinc levels of 101 EGFR-TKI-treated cancer patients were analysed and compared with those of 43 non-EGFR-TKI-treated cancer patients and 125 patients without cancer but presenting cutaneous manifestations. Additionally, the role of zinc in erlotinib-induced skin eruptions was established in a 14-day-murine model. Clinical features were further evaluated following systemic zinc supplementation in EGFR-TKI-treated cancer patients. RESULTS: EGFR-TKI-treated patients demonstrated severe cutaneous manifestations and a significant decrease in plasma zinc levels than those of the control groups. The serum zinc level and Common Terminology Criteria for Adverse Events (CTCAE) 5.0 grading of EGFR-TKI-induced skin toxicities showed a significant negative correlation (r = -0.29; p < 0.0001). Moreover, erlotinib treatment decreased the plasma zinc levels and induced periorificial dermatitis in rats confirming zinc deficiency following EGFR-TKI treatment. Zinc supplementation to the EGFR-TKI-treated cancer patients showed a significant decrease in the CTCEA grading (p < 0.0005 for mucositis and p < 0.0.0001 for all other cases) after 8 weeks. CONCLUSIONS: Skin impairment following EGFR-TKI therapy could be ameliorated through zinc supplementation. Thus, zinc supplementation should be considered for cancer patients undergoing EGFR-TKI therapy.

Using betaxolol for the prevention of paronychia induced by epidermal growth factor receptor inhibitors: a case-control cohort study.

BACKGROUND: 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, we conducted this study to determine how effectively a topical ß-blocker, betaxolol, prevents EGFR-TKI-induced paronychia. METHODS: This case-control cohort study 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 they received EGFR-TKI therapy. 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. RESULTS: In terms of the cumulative incidence of paronychia, significant differences (P < 0.01) were noted at both the 2nd and 3rd months after starting EGFR-TKIs. Furthermore, the average visual analogue scale scores were 3.125 and 6.29 in the prevention group and control group, respectively (P < 0.01). The average grades of paronychia were 1.5 and 2.12 in the prevention group and control group, respectively (P < 0.01). The average numbers of involved digits were 2.25 (range: 1-5 digits) in the prevention group and 3.03 (range: 1-7) in the control group (P = 0.07). CONCLUSIONS: Preventively using topical betaxolol can significantly decrease the incidence, VAS score, and grading of EGFR-TKI-induced paronychia.