Project Summary We recently found that World Trade Center (WTC)-exposed rescue/recovery workers who participated in the WTC Health Program (WTCHP) experienced improved survival post-cancer diagnosis compared with demographically similar cancer patients from New York State. This survival benefit was observed in both all- cause mortality and cancer-specific mortality. Further, we documented this benefit both in cancers with elevated incidence and cancers with reduced incidence compared with the general population. As part of the WTCHP, enrollees receive medical monitoring and cancer care, including treatment, at no cost to them. We hypothesized that the observed survival benefit was due to the level of care that these rescue/recovery workers receive as part of the WTCHP. We could not rule out however, the possibility that rescue/recovery workers were healthier than the reference population of New York State cancer patients prior to cancer diagnosis and therefore more likely to have a favorable cancer outcome (i.e., due to the healthy worker effect). However, no survival benefit was observed for WTC-exposed rescue/recovery not enrolled in the WTCHP – a fact that argues against the healthy worker effect as the sole factor. Now, we propose to address this knowledge gap by identifying and quantifying the sources of the observed survival benefit using an occupationally appropriate cohort as a comparison. The overall goal of the current proposal is to investigate cancer survival and survival-related factors such as cancer-specific pathology and treatment initiation in WTCHP responders (firefighters and police) and non-WTC-exposed responders (i.e., firefighters and police who met similar health criteria for hiring as WTC-exposed responders), compared with each other, by occupation, and with the general US population. Results from this proposal have the potential to elucidate the impact of WTCHP medical monitoring and treatment on survival post-cancer diagnoses and to help inform health care delivery systems. Further, while the project is focused on WTC responders, its results could have broader implications for workers occupationally exposed to environmental contaminants.