**Note 1:** Physician statement of HIV status can be used to code this data item when no other information is available.
**Note 2:** Acquired Immune Deficiency Syndrome (AIDS) lymphomas are a late manifestation of Human Immunodeficiency Virus (HIV) infection and have unique clinical and pathological features that differ from lymphomas in the general population. They have a preponderance for extranodal involvement, with central nervous system being the most common site.
**Note 3:** HIV includes types I and II. Older terminology includes Human T Lymphotropic Virus -3 (HTLV-3) and Lymphadenopathy Associated Virus (LAV).
**Note 4:** Code 9 if there is no mention of HIV/AIDS in the medical record. Do not assume that the patient is HIV negative.
**Note 5:** If patient has a history of HIV, assign code 1 even if HIV is not currently detectable.