Inclusion Criteria for All the Participants:  Ability to provide a written informed consent 40-75 years old  Exclusion Criteria for All the Participants:  Inability to comply with study procedures Pregnancy or lactating women Recipients of organ transplant or prior non-autologous (allogeneic) bone marrow transplant or stem cell transplant Recipients of blood transfusion within 7 days prior to study blood draw Recipients of any anti-cancer therapy within 30 days prior to study blood draw, due to diseases other than cancer  Inclusion Criteria for Cancer Arm Participants:  Confirmed diagnosis of a cancer or highly suspicious cases of cancer within 42 days prior to study blood draw. Tumor types in this study include lung cancer, colorectal cancer, liver cancer, ovarian cancer, gastric cancer, esophageal cancer, pancreatic cancer, biliary tract cancer, squamous cell carcinoma of the head and neck (except nasopharyngeal carcinoma) No prior or ongoing anti-cancer therapy (local or systematic) prior to study blood draw  Exclusion Criteria for Cancer Arm Participants:  Known prior diagnosis of malignancies Other current malignant diseases or multiple primary tumors No confirmed diagnosis of cancer by histopathological or radiological assessments within 42 days of study blood draw, or diagnosis of a benign disease by histopathological assessments, or inability to characterize whether the lesion is malignant or benign Non-small-cell lung cancer patients with ground-class nodularity by radiological examination  Inclusion Criteria for Benign Diseases Arm Participants:  Histopathologically confirmed or highly suspicious for benign diseases corresponding to the tumor types in the Cancer Arm within 90 days prior to study blood draw, or highly suspicious for benign diseases corresponding to the tumor types in Cancer Arm by radiological assessments or other clinical examinations No prior treatment of benign disease prior to study blood draw  Exclusion Criteria for Benign Diseases Arm Participants:  Current or history of malignancies or precancerous lesions No confirmed diagnosis or inability to characterize a benign disease by radiological, endoscopic or histopathological assessments within 42 days of study blood draw  Inclusion Criteria for Non-tumor (Healthy) Arm Participants:  No cancer-related symptoms or discomfort within 30 days prior to study blood draw No clinically significant finding by LDCT or abdominal ultrasound No clinically significant finding by breast ultrasound or Molybdenum Target Mammography Detection, or cervical liquid-based cell (TCT) detection for female participants No active hepatitis B or hepatitis C infection  Exclusion Criteria for Non-tumor (Healthy) Arm Participants:  Prior or ongoing treatment of cancer within 3 years prior to study blood draw Unexplained weight loss Prior or current major diseases, including COPD, interstitial pneumonia, viral hepatitis, liver cirrhosis, inflammatory bowel disease Prior and current adenoma of the intestine and polyp of the intestine Changes in bowel habits, bowel abnormalities, hematochezia within 30 days prior to study blood draw Uncontrolled hypertension and other cardiovascular diseases Currently severe bleeding disorders Major surgery within 24 weeks prior to study blood draw Infection requiring anti-microbial therapy within 24 weeks prior to study blood draw Current autoimmunity disease Clinically significant or uncontrolled comorbidities which, in the investigator's opinion, should be excluded