The invention provides a gene combination and application thereof in preparation of a
reagent for predicting prognosis of a patient treated with an
immune checkpoint inhibitor. Based on the combination of 55 genes, the invention develops a tumor
mutation score TMS32055 method through the
gene combination, and TMS is defined as the number of genes containing non-synonymous mutations in a specific
gene combination. TMS 55 is divided into 3 groups: TMS 55 is equal to 0, TMS 55 is greater than or equal to 1 and is less than or equal to 5, and TMS 55 is greater than 5. Compared with a group that TMS 55 is equal to 0, the patients of groups that TMS 55 is greater than or equal to 1 and is less than or equal to 5 and TMS 55 is greater than 5 have better prognosis and longer
overall survival time.The TMS55 based on the 55-gene combination has higher prediction efficiency than TMB in predicting the
overall survival after
immunotherapy, and has uniform cutoff value. Therefore, the TMS55 can beused for predicting the prognosis of patients receiving
immune checkpoint inhibition treatment, and is easier to popularize and apply in clinical practice.