The 2017 NCCN Guidelines for NSCLC recommend
epidermal growth factor receptor (EGFR)
tyrosine kinase inhibitors (TKIs) as the first-line treatment for patients with gene-sensitive mutations of pulmonary
adenocarcinoma. The TKI combination can effectively inhibit the gene mutations caused by the drug resistance and enhance the antitumor effect. However, more clinical investigations are required of the efficacy and the
adverse drug reactions (ADRs) of this combination. A 62-year-old female patient diagnosed as
lung adenocarcinoma with brain
metastasis, meningeal
metastasis, multiple bone
metastasis, and liver
metastasis was treated with the combination of
gefitinib and
osimertinib. Evident improvement was observed after 10 days of combined treatment with these
tyrosine kinase inhibitors (TKIs), including in the CT features and symptoms. The level of
tumor marker CEA decreased significantly after 40 days. However, severe
stomatitis occurred after 49 days. By analyzing the relationship between
stomatitis and TKI combined treatment based on the temporal correlation, instructions and literature reports, mechanisms, and reaction, we discovered that the combination of the two TKI drugs can increase the incidence and severity of severe
stomatitis. Following targeted treatment and
drug withdrawal, the patient fully recovered. TKI combination may increase the incidence and severity of
stomatitis, suggesting that closely care and timely withdrawal are necessary measures.