Survival and predictors of mortality among patients with virus-associated cancers in a high HIV-prevalence region in Kenya: A 10-year retrospective study.

Abstract

e22529 Background: Virus-associated cancers cause significant mortality in Africa. Understanding risk factors for mortality is crucial for effective prevention and treatment. We analyzed demographic and clinical characteristics of people with virus-associated cancers in Kisumu County, western Kenya – a region with a high HIV prevalence of 14.5% – and evaluated factors associated with mortality. Methods: We conducted a retrospective cohort study of adult patients who presented for cancer care at Jaramogi Oginga Odinga Teaching and Referral Hospital (JOOTRH) in western Kenya between January 2014 and December 2024. We included cases where viral infection is either causally associated with cancer (cervical, anal, Kaposi sarcoma) or is the strongest risk factor for cancer (penile, vaginal, vulvar). Data were extracted from paper-based patient records. We used Kaplan-Meier analysis and competing risk regression to assess survival and mortality risk factors. Results: Among 4,004 patients, 1,374 (34%) met eligibility criteria. Median age at diagnosis was 48 years (inter-quartile range 38-60), with 999 (73%) female, and 677 (49%) people with HIV. Cervical cancer was the most prevalent (n =1028, 75%), followed by Kaposi sarcoma (n = 164, 12%), penile (n =70, 5%), vulva (n =62, 4%), anal (n =36, 3%), and vaginal (n =14, 1%). 858 (64%) were LTFU and 227 (17%) were confirmed dead. Mortality among those with unknown HIV status was highest (23% versus 17% and 15% among HIV+ and HIV-, respectively). Median survival time among HIV unknowns was shortest at 2.3 months compared to 4.1 and 5.1 months among HIV+ and HIV- clients. Overall survival differed by HIV status: at year 1, probability of survival was highest among HIV- patients- at 32%, compared to 29% and 17% among HIV+ and unknown status, respectively (p < 0.05). In multivariable analyses, insurance coverage (hazard ratio [HR] 0.85, 95% CI: 0.75-0.97; p< 0.01), receiving treatment (HR: 0.39, 95% CI:0.34 -0.45; p < 0.01) and being HIV positive (HR: 0.82, 95% CI: 0.69-0.98; p < 0.01) or negative (HR: 0.74 95% CI: 0.62-0.89; p < 0.01) were associated with reduced risk of death. Conclusions: Virus-associated cancers are highly prevalent in western Kenya, with high LTFU and low survival. Insurance coverage and HIV-, and HIV+ status)were associated with lower mortality. Urgent strategies are needed to encourage early cancer detection and referral to treatment, and improve retention in care. Future research should consider testing for viral infections to attribute carcinogenicity for cancer types excluded in this analysis, such as Epstein-Barr virus (nasopharyngeal carcinoma; gastric cancer; Burkitt, Hodgkin, and diffuse large B-cell lymphoma), human papillomavirus (other head and neck cancers), and hepatitis B and C viruses (hepatocellular and intrahepatic bile duct cancers).