This study is for men and women recently diagnosed with and/or under treatment for cancer at Weill Cornell Medicine/NewYork-Presbyterian Hospital.
   
The purpose of this study is to learn about the natural history of cancer-related thrombosis (blood clots) and its causes and treatments. This research study is being done because there is a high prevalence of cancer-related blood clots, yet the cause is not well understood. About 20% of cancer patients are known to develop thrombosis and a better understanding of the underlying causes is expected to improve treatment in the future.
   
At the start of this study, blood will be drawn during a participant’s regular medical appointment. In case that the participant develops thrombosis within the two-year follow-up period, a second blood sample will be drawn in the hospital, and a third blood sample will be taken two to four weeks after the start of anticoagulant therapy. Participants’ medical information will be recorded for up to 2 years.
   
Participants will be contacted periodically by the research team to find out if they have had any thrombotic events. It is possible that a participant will be treated at another hospital for these types of thrombotic events.
   
 Participants will be in the study for up to 2 years.