Differences in the Course of CD4 and CD8 Cells After Chemoradiotherapy in People Living with HIV with Anal Cancer.

Incidence of anal carcinoma (AC) in people living with HIV (PLWH) is increased compared to the general population. Adverse effects of chemoradiotherapy (CRT) on the immune system are associated with a significant detrimental prognosis on overall survival in patients receiving CRT for solid tumors. The aim of this study was to evaluate immunological factors, in particular the differences in recovery of CD4⁺ and CD8⁺ cell counts before and after CRT for AC in PLWH. Retrospective single-center chart review extraction to analyze immunological data collected from PLWH with AC; descriptive statistics were used. Thirty-six PLWH with histologically proven AC were included in the analysis. Absolute CD4 cell count 60 months after CRT was 67.2% of the value at the beginning of CRT, whereas the CD8 cell count reached 82.3%. These differences were statistically significant (p = .048), whereas CD4/CD8-ratio remained stable. The findings of the presented study regarding CD4⁺ and CD8⁺ cell recovery after CRT are congruent with results from prior studies in non-HIV infected patients. Although not reaching the level of prior CRT T cell numbers, the ability to generate CD8⁺ cells seems to be better recovered, while CD4⁺ regeneration is more impaired. These observations are best explained by faster recovery of CD8⁺ cells via thymic-independent pathways, which are not available for regeneration of CD4⁺ cells. Further studies with larger numbers of patients are required to analyze the specific CD4⁺ and CD8⁺ cell subsets.