Background HIV infection is associated with increased risk of cancer: AIDS-defining cancers (ADC): Kaposi’s sarcoma (KS), non-Hodgkin lymphoma (NHL), cervix cancer. non-AIDS-defining cancers (NADC): Hodgkin lymphoma (HL), anal cancer, lung, head, neck, hepatocarcinoma. Purpose To analyse patients with antiretroviral therapy and chemotherapy, type of cancer and associated risk factors. Materials and Methods Descriptive study of patients with antiretroviral and chemotherapy between 2004–2011, extracting data from medical records and the Farmatools programme, analysing using SPSS 11.0. Results33 patients were obtained (3.7% of all HIV patients on antiretroviral treatment); 82% men: 16 with ADC (11 NHL, 3 KS, and 2 with NHL and KS) and 17 with NADC (5 HL, 3 lung cancer, 3 head-neck, 3 anal, 1 ovary, 1 gastric and 1 chronic lymphocytic leukaemia). When cancer was diagnosed patients presented: CD4<200 cells/microliter (27.3%), detectable viral load (VL) (33.3%), C3 category (63.6%), smokers (63.6%), human papillomavirus (HPV) (6.1%), Epstein Barr virus (21.2%), human herpes virus 8 (HHV8)(21.2%), hepatitis B-C (48.5%), intravenous drug addict (24.2%). 8 patients died. 80% KS patients and 66.7% head-neck cancer had CD4<200 (P = 0.036). 62.5% of those who died presented CD4<200 (P = 0.009). 66.6% of anal cancer patients presented HPV (P = 0.006). 100% of KS presented HHV8 (P = 0.002). Conclusions 3.7% of HIV patients on treatment developed neoplasms, more than 50% were NADC, of which 88% started in patients with an undetectable VL, confirming a nice immunological status when cancer was diagnosed. No conflict of interest.