Hodgkin lymphoma (HL) and non-Hodgkin lymphomas (NHLs) behave differently. HL tends to be less aggressive than NHLs, and it often involves just a single lymph node or group of lymph nodes at the time of diagnosis. HL is less likely than NHLs to involve lymph nodes in the chest or abdomen or tissues and organs outside the lymphatic system (such as skin, bones, stomach, intestines, or central nervous system). HL is one of the most treatable hematologic cancers, with a cure rate as high as 70 to 80 percent. NHLs have a more variable prognosis, depending on the type of tumor and other factors, including the person's age. Some people with early stage disease and no risk factors for poor outcome have a high probability of cure rate, but many individuals with advanced disease and other risk factors for poor outcome have a 5-year survival of approximately 50 percent.