Abstract 4943 Background:The use of highly active antiretroviral therapy (HAART) has dramatically improved the prognosis of AIDS-related Non-Hodgkin lymphoma (NHL), causing a remarkable increase in patients' long-term survival. On the other hand, with the introduction of HAART, the incidence of non-AIDS-related malignancies is increasing among patients with HIV infection. The incidence of second neoplasms after treatment of aggressive NHL have been reported to be higher than in the general population. Nevertheless, there is scarce information regarding second malignancies occurring in HIV-infected patients after NHL treatment. We sought for second neoplasms among patients treated of AIDS-related NHL, hence suffering from 2 conditions which may predispose them to develop malignancies: therapy for lymphoma and HIV infection. Methods:We conducted a retrospective study of patient data on AIDS-related NHL individuals diagnosed between 1989 and 2010 in our institution. Demographic, HIV infection, and lymphoma data on each case were collected. Two groups were further considered: patients who did not take HAART at all, and those who started HAART at any stage of their HIV infection. Continuous and categorical variables are presented using descriptive statistics. Survival analyses were performed using the Kaplan-Meier method and compared using the log-rank test. P-values of less than 0.05 were considered statistically significant. Results:Out of a series of 146 patients diagnosed with AIDS-related NHL, 138 patients were eligible for the study with a median follow-up of 8.24 years: 70 patients belonged to the no-HAART group, and 68 to the HAART group. Most interesting data regarding both groups are listed in table 1. Briefly, patients in the HAART group were older at the time of lymphoma diagnosis than those who did not receive it (p=0.024); in addition, there were more male patients in the no-HAART group (p=0.011). These differences show the demographic changes among HIV-infected patients in the HAART era. Furthermore, a higher number of complete responses (CR) to lymphoma treatment was observed in the HAART group (p<0.001). Overall survival (OS) and disease free survival (DFS) were significantly longer for patients who took HAART (p<0.001 and p<0.001 respectively).NAge mean (SD)Male genderTreated n (%)CT n (%)RT n (%)CR n (%)5-yr OS %2-yr DFS%Second neoplasm n (%)No HAART7037 (15)6244 (63)39 (56)6 (9)11 (16)2.918.20HAART6842 (10)4865 (95)64 (94)10 (15)40 (59)4979.54 (10%)Four out of the 40 patients at risk (10%), developed a second malignancy in the HAART group, and none in the no-HAART one. However, no statistically significant differences were found, probably due to the low number of cases. The most important features of the 4 patients with a second malignancy are listed in table 2. All 4 patients were diagnosed with diffuse large B-cell lymphoma (DLBCL), were treated with CHOP, and had a prior diagnosis of AIDS. Two of the 4 were on HAART at lymphoma diagnosis (one of them in both virological and immunological response). The patient with hepatocarcinoma was HCV positive. As shown in table 1, three of the patients had responded to HAART when the second neoplasm (carcinoma) was diagnosed; and the reminder, who did not respond to HAART, developed a Kaposi sarcoma. All four patients died because of neoplasm progression.Table 2PatientsAgeGenderHIV risk conditionHAART onsetTime to neoplasm (years)Type of NeoplasmHIV load (copies/mL)CD4/μL143MIVDUBefore NHL7.8Hepatocarcinoma0256240FSexualAfter NHL CT1.2Anal carcinoma0320357MSexualBefore NHL0.4Kaposi sarcoma32031941427FSexualConcomitant with NHL CT10.9Vaginal carcinoma0436 Conclusions:As expected, a higher frequence of second neoplasms was observed after treatment of AIDS-related NHL among patients who receive HAART. Second malignancies were non-HIV related neoplasms in patients with response to HAART.Abbreviations: CT, chemotherapy; RT, radiotherapy; IVDU: intravenous drug user. Disclosures:No relevant conflicts of interest to declare.