Nov 29, 2023

High TMB Linked to Better Outcomes of ICI Therapy in Gastric Cancer Patients with a high tumor mutational burden had significantly longer progression-free survival and overall survival. Source: Getty Images Patients with gastric cancer have better outcomes of immune checkpoint inhibitor (ICI) treatment if they have a high tumor mutational burden (TMB), according to a meta-analysis published in International Immunopharmacology. Researchers found that overall survival (OS) and progression-free survival (PFS) were longer in patients with a high TMB, and these benefits were drive by Asian patients. This meta-analysis included 11 retrospective studies of patients with gastric or gastroesophageal cancer treated with ICIs. Nine studies were conducted in Asian countries and 2 in non-Asian countries. Continue Reading Patients received combination treatment in 6 studies and ICI monotherapy in 5 studies. The ICIs included nivolumab, pembrolizumab, atezolizumab, tislelizumab, and toripalimab. Using data from 8 studies, the researchers found that patients with a high TMB had significantly longer OS than patients with a low TMB (hazard ratio [HR], 0.65; 95% CI, 0.55-0.77; P <.001). Using data from 10 studies, the researchers found that patients with a high TMB had significantly longer PFS than patients with a low TMB (HR, 0.51; 95% CI, 0.33-0.77; P =.001). A subgroup analysis revealed that the OS benefit was significant in Asian patients with a high TMB (HR, 0.56; 95% CI, 0.43-0.72; P <.001) but not in non-Asian patients with a high TMB (HR, 0.61; 95% CI, 0.32-1.16; P =.133). Similarly, the PFS benefit was significant in Asian patients with a high TMB (HR, 0.45; 95% CI, 0.28-0.72; P =.001) but not in non-Asian patients with a high TMB (HR, 0.68; 95% CI, 0.31-1.48; P =.322). The OS in high-TMB patients was similar whether they received combination therapy or monotherapy. The PFS benefit, on the other hand, was significant in high-TMB patients who received monotherapy (HR, 0.39; 95% CI, 0.22-0.67; P =.001) but not in those who received combination therapy (HR, 0.84; 95% CI, 0.65-1.08; P =.192). “This meta-analysis demonstrated that gastric cancer patients with high TMB showed significant benefits from ICIs compared to … low TMB patients, particularly in Asian populations,” the researchers wrote. “In the future, there is a requirement for a large number of RCTs [randomized clinical trials] to prove that TMB is a feasible predictor for prognosis of gastric cancer patients treated with ICIs.” Reference