Pencegahan Kanker Penelitian Sofia Peterson AMERICAN CANCER SOCIETY, ANDREW T. CHAN, CANCER PREVENTION, CENTER FOR YOUNG, CENTER FOR YOUNG ADULT COLORECTAL CANCER, CLINICAL AND TRANSLATIONAL EPIDEMIOLOGY UNIT AND DIVISION OF GASTROENTEROLOGY, DANIEL SIKAVI, DISEASE PREVENTION, DIVISION, GENERAL BRIGHAM, HPV VACCINE, JAMA ONCOLOGY, LONG H. NGUYEN, MASS, MASS GENERAL, MASS GENERAL BRIGHAM, MASS GENERAL CANCER CENTER, MASSACHUSETTS GENERAL HOSPITAL, MEDICINE, NURSES, NUTRITION, RESEARCH, SIKAVI, U. S. PREVENTIVE SERVICES TASK FORCE, USPSTF Aspirin dan Pencegahan Kanker Kolorektal