RBP4 and neoplasm: Taking THCA as an example, 12 genes were finally selected in the model, and one of the corresponding fuzzy rule for thyroid carcinoma classification was: IF (APOD is small) ^ (CDKL2 is large) ^ (CLEC4F is medium) ^ (CSF2 is small) ^ (HAPLN1 is medium) ^ (ITIH2 is medium) ^ (KLHDC8A is large) ^ (KLK13 is medium) ^ (MMP23A is small) ^ (MYOC is small) ^ (R3HDML is small) ^ (RBP4 is medium), THEN the sample is a tumor sample.