Non-Hodgkin Lymphoma

Non-Hodgkin lymphomas (NHL) are a heterogeneous group of malignancies originating from B- or T-lymphocytes and engaging lymphoid tissue. Clinically, NHL subtypes range from chronic indolent to aggressive life-threatening diseases. The incidence of NHL overall increased dramatically worldwide during the latter half of the twentieth century but has now leveled off in many countries. Although some etiologic factors have been identified, most newly diagnosed cases of NHL as well as the previous rise in incidence remain largely unexplained. Well-established risk factors include severe immune suppression following HIV/AIDS and organ transplantation, autoimmune and inflammatory disorders, some infectious agents, and family history. More recently, lifestyle factors have also been linked with certain subtypes of NHL. Through the work of the international InterLymph consortium, several subtype-specific genetic susceptibility variants have also been revealed, promising to shed further light on mechanisms of lymphomagenesis.