This study is designed to investigate the epidemiologic, genetic, laboratory and clinical characterization of individuals with cancer (gastric, colorectal, esophageal, liver, prostate, lung, breast and endometrial cancer, etc.). We will accrue approximately 1600 patients as experimental group. The control group consists of subjects who will be confirmed without cancer. We will explore the environmental (including family history, life style, diet, physical activity, neuropsychological functioning，plasma levels of oxidative stress factors, angiogenic factors, and tumor markers, etc.) and genetic (including oxidative stress factors and angiogenic factors, etc.) risk factors. We will study the association between various environmental risk factors with the clinical characterization and correlation between the genetic polymorphisms and the presence of various cancer.