CROI 2016 Abstract eBook

Abstract Listing

Poster Abstracts

613 Risk of Cancer in HIV-Positive Adults on ART in South Africa: A Record Linkage Study Mazvita M. Sengayi 1 ; Adrian Spoerri 2 ; Matthias Egger 3 ; Janet Giddy 4 ; Mhairi Maskew 5 ; Elvira Singh 1 ; Julia Bohlius 2 ; for the International Epidemiologic Databases to Evaluate AIDS Southern Africa (IeDEA-SA) 1 Natl Cancer Registry, NHLS, Johannesburg, South Africa; 2 Inst of Social and Preventive Med, Univ of Bern, Bern, Switzerland; 3 Univ Hosp Bern, Bern, Switzerland; 4 McCord Hosp, Durban, South Africa; 5 Univ of the Witwatersrand, Wits Hlth Consortium, Johannesburg, South Africa Background: The surveillance of HIV-related cancers in South Africa is hampered by the lack of systematic collection of cancer diagnoses in HIV cohorts and the absence of data on HIV status in cancer registries. To estimate cancer incidence and explore risk factors for developing infection-related and non-infection-related cancer, we conducted a probabilistic record linkage study of ART programs providing care for adults and the National Cancer Registry in South Africa. Methods: We used data for the period 2004-2011 from two ART programs (McCord Hospital, KwaZulu-Natal and Themba Lethu Clinic, Gauteng province) and linked it to the cancer registry data for the same period. We used probabilistic record linkage methods to identify patients with both HIV and cancer. Linkage variables were names, date of birth and gender. We calculated cancer incidence rates and hazard ratios (HR) with 95% confidence intervals (CI) frommultivariable Cox regression models adjusted for sex, age, CD4 cell counts and hemoglobin levels at start of ART for infection-related and non-infection-related cancers as defined by the International Agency for Research on Cancer . Results: We included 23,120 patients, 64%were women, median age at starting ART was 36 years (IQR 31-42) and median CD4 cell count was 109 cells/µL (IQR 45-179). During 59,101 person-years (pys) of follow-up 851 patients developed incident cancers for an overall incidence rate of 1,315/100,000 pys (95% CI 1,225-1,410). Cancers with the highest incidence rates in men were Kaposi sarcoma (KS), non-Hodgkin’s lymphoma (NHL), oesophagus, conjunctiva and oropharyngeal cancers. In women, cancers with the highest incidence rates were cervical cancer, KS, breast, NHL and conjunctiva (Figure). The risk of developing infection-related cancer increased with lower CD4 cell counts at start ART (<100 versus >=350 cells/µL: adjusted HR 0.24, 0.08-0.76) and with lower hemoglobin levels (adjusted HR: 0.92, 95% CI 0.87-0.96). For cancers not associated with infections, cancer risk increased with age at ART start (>=56 versus 16-25 years: adjusted HR 2.63, 95% CI 1.08-6.39). Conclusions: Incidence of cancer in HIV-positive South Africans in the era of potent ART remains high, particularly for AIDS-defining cancers and infection-related cancers. There is a need to evaluate and implement cancer-specific prevention strategies in the HIV-positive population in South Africa.

Poster Abstracts

614 No Difference in Stage at Cancer Diagnosis by AIDS Status Among HIV-Infected Adults

Surbhi Grover 1 ; Heidi M. Crane 2 ; John Gill 3 ; James J. Goedert 4 ; Mari M. Kitahata 2 ; Richard Moore 5 ; Sonia Napravnik 6 ; Anita Rachlis 7 ; Michael J. Silverberg 8 ; Keri N. Althoff 9 1 Univ of Pennsylvania, Philadelphia, PA, USA; 2 Univ of Washington, Seattle, WA, USA; 3 Univ of Calgary, Calgary, AB, Canada; 4 NIH, Bethesda, MD, USA; 5 Johns Hopkins Univ, Baltimore, MD, USA; 6 Univ of North Carolina at Chapel Hill, Chapel Hill, NC, USA; 7 Sunnybrook Rsr Inst, Sunnybrook Hlth Scis Cntr, Toronto, ON, Canada; 8 Kaiser Permanente Northern California, Oakland, CA, USA; 9 Johns Hopkins Bloomberg Sch of PH, Baltimore, MD, USA Background: HIV-associated immune suppression has been linked to an increased risk of certain cancers, but whether this risk is translated into different stages at cancer diagnosis, or risk of death after cancer diagnosis, is unclear. We estimated the effect of prior AIDS-defining illness (ADI) as a surrogate for advanced HIV disease progression on cancer stage at diagnosis and subsequent mortality risk. Methods: HIV-infected adults (>=18 years of age) with validated diagnoses of anal, oropharynx (OP), cervical, lung cancer, or Hodgkin lymphoma (HL) from 1 Jan 2000 to 31 Dec 2009 in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) were included. NA-ACCORD participants are HIV-infected adults who successfully link into care. The distribution of stage at cancer diagnosis was compared in those with and without a prior ADI. Stage at diagnosis was identified via local review of medical records by trained medical record abstractors under the supervision of physician or via cancer registries. Analyses were stratified by type-specific cancer. Adjusted mortality rate ratios [aMRRs] and 95% confidence intervals ([,]) were estimated using Poisson regression models accounting for sex, race, smoking status, CD4 count, HIV RNA, ART use, and cancer stage, all measured at cancer diagnosis; age was time-varying. Results: Of the 81,865 participants, 814 had validated type-specific cancer diagnoses of interest (n=162 anal, n=5 cervical, n=444 lung, n=114 OP, n=89 HL); 642 (79%) with a prior ADI and 728 (89%) with ART use prior to cancer diagnosis. Cancer stage was comparable by prior ADI diagnosis for each cancer (Figure 1). Prior ADI diagnosis increased mortality rates after cancer diagnosis for each cancer, except cervical cancer as none died after cervical cancer diagnosis. After adjustment for age, sex, race, smoking, ART use, CD4 count, HIV RNA, and cancer stage at diagnosis, the aMRRs comparing those with vs. without a prior ADI at cancer diagnosis were as follows: anal: 1.5 [0.8, 2.6]; lung: 1.6 [1.3, 2.0]; OP: 1.9 [0.9, 3.6]; and HL: 1.9 [0.8, 4.4]. Conclusions: A marker of at least one prior episode of advanced HIV disease (i.e. a prior ADI) was not associated with differences in stage at diagnosis or risk of death after cancer diagnosis (except for lung cancer) in this population of HIV-infected adults with access to care.

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CROI 2016