The purpose of this contract is to increase the value of the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO) and National Lung Screening Trial (NLST) resources by: 1) continuing the follow-up of participants for an additional 5-year period (2016-2021); 2) updating key exposure data and collecting additional data; 3) collecting additional clinical data; 4) substantially increasing the number of accrued incident cancer; 5) strengthening the trials? abilities to evaluate the long-term effects of screening on cancer mortality; and, 6) allowing for a continued opportunity to collect additional exposure data and/or biospecimens.