Abstract

INTRODUCTION

Skin toxicities are the most common adverse events of the tyrosine kinase inhibitors that are used to EGFR mutant lung cancer. In our study, we aimed that investigated the relationship between skin toxicities and vitamin D levels in the patients with EGFR mutant and treated with erlotinib.

METHODS

EGFR mutant patients that admitted to Medical Oncology department of Atatürk Chest and Chest Surgery Hospital between 2014 – 2018 are included in this study. The patient’s data were collected retrospectively.

RESULTS

Totally, 78 patients that have EGFR mutation and treated with erlotinib are included in this study. The median level of vitamin D at the diagnosis was 34.6 (5-88) ng/ml. The patients were stratified two group according to vitamin D level. The 42 of whom (53.8 %) had vitamin D level < 20 ng/ml and 36 patients (46.2 %) had vitamin D level ≥ 20 ng/ml. Grade 2 -3 skin toxicities were significantly higher in the patients had vitamin D level < 20 ng/ml (p: 0.038).

DISCUSSION AND CONCLUSION

In our study, we found that the higher grade erlotinib related skin toxicities were more frequently in the patients that had low vitamin D level. Both of the erlotinib treatment and low vitamin D level may have contributed to the inhibition of keratinocyte proliferation, differentiation and cell cycles.