GPT and head and neck cancer: This cohort included 27 cancer types, and Skin Cancer (Non − Melanoma) had the highest CDKN2A ALT frequency (46.7% were CDKN2A-DEL and 4.8% were CDKN2A-MUT), followed by melanoma, mesothelioma, pancreatic cancer, head and neck cancer, bladder cancer and gastrointestinal stromal tumor (Fig. 2B).