It is well-known that Tryptophan metabolism through the Kynurenine pathway and activation of the Aryl hydrocarbon receptor promote immune evasion.23 A concurrent study on the same treatment regimen in patients with advanced gastroenteropancreatic neuroendocrine tumors has revealed a significant association between heightened Kynurenine pathway activation and poor clinical outcomes.24 This suggests that Kynurenine pathway activation might also explain the reduced sensitivity observed in sarcoma patients. The gene discussed is AHR; the disease is sarcoma.