Approximately 10% of individuals over the age of 65 years show clonal expansion of cancer-associated mutations in their blood.[23] A Chinese lung cancer gene mutation study showed that ALK, KRAS, and BRAF gene abnormalities were mainly found in patients aged <60 years, while other genes were dominant in elderly patients.[24] Therefore, proto-oncogene is not the only important reference factor for elderly cancer patients, and the corresponding targeted therapies such as lenvatinib mentioned above, have limited efficacy. This evidence concerns the gene KRAS and lung carcinoma.