CROI 2024 Abstract eBook

Abstract eBook

Poster Abstracts

ART are needed to reduce the DLBCL incidence in the Black population in South Africa. The reduced DLBCL ASIRs in 2020-2021 might be partially attributed to the COVID-19 pandemic.

the importance of earliest possible diagnosis of HIV and prompt initiation of ART to ensure optimal sustained risk reduction of both ADC and NADC.

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Clinical Predictors and Outcomes of Anal Cancer for People With HIV in an Inception Cohort Edward Cachay 1 , Tari Gilbert 2 , Huifang Qin 2 , Christopher Mathews 2 1 University of California San Diego, San Diego, CA, USA, 2 University of California San Diego, La Jolla, CA, USA Background: The heterogeneity of risk for invasive anal cancer (IAC) among individuals living with HIV (PWH) underscores the importance of identifying clinical predictors to inform a shared decision-making framework for screening. We investigated predictors of IAC and described outcomes among those diagnosed with IAC. Methods: The study clinic assembled a longitudinal HIV inception cohort of anal cancer screening outcomes. Screening procedures included anal cytology, digital anorectal examination, high-resolution anoscopy (HRA), and access to ablative treatments. We computed the adjusted probabilities of developing IAC over 5 and 10 years since the initial screening anal cytology. We describe the clinical outcomes of those diagnosed with IAC. Cox proportional models with inverse probability weighting were fit to account for differential screening in the cohort and to construct a nomogram for predicting IAC risk. Results: Between 2007 to 2020, 8139 PWH received care at UCSD Owen Clinic, of whom 4105 (49.8%) underwent at least 1 anal cytology test and were followed for a median of 5.5 years (up to 13 years). Among them, 32 individuals develop IAC (age range at diagnosis 29-76 years). Those diagnosed with IAC following their first anal cytology were more likely to be younger and exhibit anal high-grade squamous intraepithelial lesion (aHSIL) on initial or subsequent follow-up cytology. Additionally, they showed lower median and nadir CD4 cell counts and underwent anal ablative treatment less frequently. Analyses did not reveal differences in IAC development based on gender identity, race, ethnicity, HIV risk factor, or tobacco use. The highest risk of IAC was associated with PWH having nadir CD4 cell count less than 200 with a hazard ratio (HR) of 3.73 (95%CI 1.61-8.54) and cytology aHSIL (HR 3.75 1.47-9.47). PWH with a combined nadir CD4 cell count of less than 200 and cytology aHSIL will have a 5- and 10-year probability of IAC of 2.9% and 3.7%, respectively (Figure). Of 32 PWH diagnosed with IAC, 7 died due to cancer progression. All who died due to IAC had clinical stages IIIA or higher, and of them, 3 had declined to have an HRA ever, and 1 opted out of recommended HRA surveillance. Conclusion: PWH with nadir CD4 cell count below 200 and cytology aHSIL have the highest risk of anal cancer within 5 years of follow-up. All patients who died had anal cancer clinical stages IIIA or higher at diagnosis, highlighting the importance of early diagnosis through HRA cancer surveillance.

Poster Abstracts

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Incidence of Diffuse Large B-Cell Lymphoma in Relation to the HIV Epidemic in South Africa 2011-2021 Carole Metekoua 1 , Mazvita Muchengeti 2 , Yann Ruffieux 1 , Patricia Kellett 2 , Matthias Egger 1 , Eliane Rohner 1 , Tracey Wiggill 3 1 University of Bern, Bern, Switzerland, 2 National Health Laboratory Service, Johannesburg, South Africa, 3 Stellenbosch University, Stellenbosch, South Africa Background: Diffuse large B cell lymphoma (DLBCL) is HIV-associated and the most common type non-Hodgkin lymphoma worldwide. We examined the impact of the HIV epidemic and antiretroviral therapy (ART) roll-out on incident DLBCL in South Africa by comparing characteristics and temporal trends of incident DLBCL between the Black (high HIV prevalence) and the White (low HIV prevalence) populations Methods: We identified DLBCL diagnosed in South Africa from 2011-2021 in the pathology-based National Cancer Registry using International Classification of Disease Oncology, 3rd Edition morphology codes. Using direct standardization, we computed age-specific incidence rates and estimated yearly age standardized incidence rates (ASIR). We used Joinpoint regression to estimate annual percentage changes (APC) in the ASIR of DLBCL. Results: In South Africa, 13,560 DLBCL were diagnosed from 2011-2021; 55% of them (n=7410) were among men. The median age at DLBCL diagnosis was 47 years (IQR=37-59). Two-thirds of incident DLBCL occurred in Black (65% [n=8790]) and 22% in White individuals (n=3006). The incidence of DLBCL was highest among middle-aged adults in the Black population and older White people (Figure A). The overall ASIR of DLBCL per 100,000 persons was 5.8 in the White and 1.8 in the Black population. The ASIR of DLBCL was higher in the White population across all calendar years (Figure B). In the Black population, we noted an annual increase of 5.9% (95%CI 0.02 to 37.1) from 2011-2017 with a declining trend thereafter (APC -4.2%; 95%CI -22.8 to 3.7). Similarly, in the White population, the ASIR of DLBCL showed a yearly increase of 5.6% (95%CI 4.8 to 7.9) from 2011-2019 with a declining trend thereafter (APC -3.4%; 95%CI -8.1 to 2.4). Conclusion: Whereas incident DLBCL in the White population mostly occurs among elderly individuals, the high DLBCL incidence rates among middle-aged Black individuals in South Africa indicate that HIV primarily drives incident DLBCL in this population. However, despite the introduction of ART in 2004, the DLBCL rates continued to increase in the Black population for more than a decade and only decreased one year after introducing the universal-test-and treat policy in 2016. This suggests that wide coverage and timely initiation of

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