Tumor Mutation Burden Might Predict Who Is Suited for Adjuvant Chemotherapy

Patients with lung adenocarcinomas who have high TMB likely will not benefit from adjuvant chemotherapy, according to Prashanth Ashok Kumar, MD, and colleagues. Their findings were published in Clinical Lung Cancer.

Using the LACE Bio II database, the researchers identified 375 patients who were then divided according to adenocarcinoma subtype. The following subtypes were included in the analysis: lepidic, acinar/papillary, micropapillary/solid (MIP/SOL), mucinous (MUC), and others. Study end points included OS, DFS, and lung cancer-specific survival (LCSS). The survival outcomes were compared using the Kaplan-Meier method and log-rank test based on PD-L1, TMB, and tumor-infiltrating lymphocytes (TILs).

MIP/SOL was the subtype most commonly positive for different biomarkers. In addition, patients who were PD-L1 negative with high TMB had better OS and DFS outcomes relative to those who were PD-L1 negative with low TMB.

Regarding adjuvant chemotherapy, those with high TMB were predicted to have worse OS outcomes.

“The high TMB group had a poor outcome with [adjuvant chemotherapy], suggesting that this group may be better served with immune checkpoint therapy,” the authors wrote.

Adjuvant chemotherapy showed a survival benefit in patients with marked TILs, who had better outcomes for DFS and LCSS. DFS was also positively associated with patients with marked TILs and low TMB.