Relative Dose Intensity and Pathologic Response Rates in Patients With Breast Cancer and With and Without HIV Who Received Neoadjuvant Chemotherapy

Patients who are HIV-positive and have breast cancer have worse overall survival (OS) compared with patients who are HIV-negative. Pathologic complete response (pCR) and relative dose intensity (RDI) of chemotherapy are associated with survival. We assessed whether pCR and RDI rates were lower for patients who are HIV-positive and received neoadjuvant chemotherapy (NACT). METHODS: This was a prospective cohort analysis of patients initiating NACT in Botswana (February 2017 to September 2019). Primary outcomes were pCR and RDI; secondary outcomes were OS and toxicity. HIV status and zidovudine (ZDV) treatment were stratification factors. Multivariable analysis was used to control for confounding. RESULTS: In total, 26 of 110 enrolled individuals were HIV-positive. In univariable analysis, HIV-positive (odds ratio [OR] = 0.2; P = .048) and RDI < 0.85 (OR = 0.30; P = .025) were associated with pCR. In multivariable analysis, the magnitude of association decreased for HIV-positive (OR = 0.28; P = .11), but RDI < 0.85 remained independently associated with pCR (OR = 0.32; P = .035). Patients who are HIV-positive had significantly lower mean RDI, and those on ZDV had significantly lower RDI. Ninety-one (83%) were stage III with 2-year OS significantly worse for patients who are HIV-positive (58% v 74%). Hazard ratio for all-cause mortality was 2.68 (95% CI, 1.17 to 6.13; P = .028) in patients who are HIV-positive compared with patients who are HIV-negative. Toxicity rates were similar despite patients who are HIV-positive receiving significantly lower dose intensity chemotherapy. CONCLUSION: Patients who are HIV-positive and have breast cancer in Botswana have lower pCR rates and also receive lower dose intensity therapy, which may contribute to worse OS. Patients who are HIV-positive on ZDV-containing regimens received even lower dose intensity of NACT. Administering optimal dose intensity in patients who are HIV-positive remains a challenge, and targeted interventions that address modifiable risk factors are needed to improve therapy delivery and outcomes.