External validation of a serum tumor marker algorithm for early prediction of no durable benefit to immunotherapy in metastastic non-small cell lung carcinoma. - Schuurbiers, Milou M. F.; van Delft, Freek A.; Koffijberg, Hendrik; IJzerman, Maarten J.; Monkhorst, Kim; Ligtenberg, Marjolijn J. L.; van den Broek, Daan; van Rossum, Huub H.; van den Heuvel, Michel M. (Tumour biology: the journal of the International Society for Oncodevelopmental Biology and Medicine, 2025)