Inclusion Criteria:  The age is 18-90 years old (including 18 and 90 years old); The subjects knew about the experiment and signed the informed consent voluntarily; The subjects complicated with tumor diseases and atherosclerotic plaques; The subjects received regular PD-1 inhibitor treatment; The subjects had ultrasound images of atherosclerotic plaques before- and after- or during PD-1 blockade treatment at the two different timepoints; The subjects received regular treatments of PD-1 inhibitor during the two timepoints of artery ultrasound examinations; The subjects who had ultrasound images before the initiation of first-dose PD-1 inhibitor, the interval between these two timepoints should be restricted within 1 month; The subjects who had ultrasound images after 3 months of PD-1 inhibitor treatment.  Exclusion Criteria:  Subjects stop receiving PD-1 inhibitor treatments during follow-up; Subjects are reluctant to continue to be involved in this study; Known pregnant and lactating women; Plaque areas can not be calculated because of the quality of ultrasound image; Other situations that the researchers judged were not suitable for inclusion.