# Cancer Risk in Men with HIV in Japan: An 18-Year Single-Center Cohort Study

## TL;DR

Men with HIV in Japan have a much lower risk of AIDS-related cancers over 18 years, but still face high risks for anal and oral/pharyngeal cancers.

## Contribution

This study provides updated cancer risk data for men with HIV in Japan, highlighting the shift from AIDS-defining to non-AIDS-defining cancers.

## Key findings

- The risk of AIDS-defining cancers like Kaposi’s sarcoma and AIDS-related lymphoma dropped significantly over 18 years.
- Non-AIDS-defining cancers like anal and oral/pharyngeal cancers remain at high risk compared to the general population.
- Overall cancer risk in men with HIV has decreased to levels similar to the general population.

## Abstract

Effective treatments allow people with HIV to live longer, but this changes their long-term health risks, including their risk of cancer. We analyzed cancer trends in 3793 men with HIV in Japan over an 18-year period from 2007 to 2024 to understand these changes. We found that the risk of AIDS-defining cancers (Kaposi’s sarcoma and AIDS-related lymphoma) has decreased dramatically. The overall risk of cancers other than the AIDS-defining cancers has also decreased to levels similar to those of the general population. However, the risk for some specific non-AIDS-defining cancers, particularly anal cancer and oral/pharyngeal cancers, remains persistently high. This research shows that cancer prevention strategies for people with HIV in Japan need to be adapted. Healthcare providers should refocus efforts on screening and preventing the specific high-risk cancers to ensure the long-term health of patients with HIV.

Objectives: Among people with HIV (PWH), the epidemiology of malignant tumors has shifted from AIDS-defining malignancies (ADMs) to non-AIDS-defining malignancies (NADMs). This study examined temporal changes in the standardized incidence ratio (SIR) of malignant tumors in an HIV cohort in Japan. Methods: A retrospective cohort study was conducted of 3793 men treated for HIV at Osaka National Hospital between 2007 and 2024. Diagnoses of malignant tumors were identified from medical records and the expected numbers of cases were calculated using cancer incidence rates for the general male population of Japan. SIRs and 95% confidence intervals (CIs) were calculated and temporal changes across four periods (2007–2011, 2012–2016, 2017–2020, and 2021–2024) were evaluated using the p for trend. Results: The overall SIR for malignant tumors decreased from 5.12 (95% CI: 4.02–6.43) in 2007–2011 to 0.86 (95% CI: 0.64–1.14) in 2021–2024, mainly owing to a decline in ADMs (SIR: 111.93 to 5.70), including Kaposi’s sarcoma (SIR: 4269.39 to 547.26) and AIDS-related lymphoma (SIR: 62.18 to 3.13). The overall SIR for NADMs was similar to that of the general population (1.04; 95% CI: 0.89–1.22), and decreased from 1.64 to 0.69, but the risks of anal cancer (SIR 40.63) and oral/pharyngeal cancer (SIR 3.16) remained high. Conclusions: Among men with HIV in Japan, the overall risk of ADMs and NADMs has decreased; however, the risk of specific NADMs remains high. Cancer prevention strategies for PWH need to focus on high-risk NADMs.