Practice Patterns in the Treatment of Head and Neck Malignancies with or without Comorbid HIV Infection in Botswana

Abstract

Head and neck cancer (HNC) is the fifth most common cancer in sub-Saharan Africa (SSA), a region with hyperendemic HIV infection. Individuals with HIV have higher rates of HNC, however the effect of HIV infection on treatment toxicity and oncologic outcomes is not well-characterized. The objective of this study was to prospectively evaluate patterns of oncologic care and outcomes for HNC patients with or without HIV infection in Botswana, a resource-limited SSA country that has one of the highest rates of HIV infection in the world. Patients with HNC attending an oncology clinic were enrolled in a prospective observational cohort registry in Gaborone, Botswana from 2015 through 2019. Clinical characteristics were analyzed to identify factors associated with oncologic treatment and outcomes. Overall survival (OS) was evaluated via Kaplan-Meier and associations with survival and toxicity were analyzed via Cox proportional hazards and logistic regression analyses, respectively. Secondary analysis by HIV infection status was then performed. A total of 149 patients were enrolled with a median follow-up of 23 months. The most common HNC anatomical subsites were oral cavity (37%), larynx (9%), salivary gland (9%), oropharynx (9%), nasopharynx (9%), and orbit (9%). Patients were likely to present with advanced disease (60% of patients had T4 primary disease) and have a long interval from pathologic diagnosis to the start of radiation treatment (RT; median time of 2.5 months [IQR: 1.6-5.4 months]). Only 29% of patients received definitive RT, 19% received chemotherapy, and 8% received surgery as part of their management plan. Median overall survival (OS) was 36.2 months (95% CI: 20.6 – 51.8 months) with a 2-year OS of 58%. Low hemoglobin (<12 g/dL) was associated with poorer survival on multivariable analysis (HR 2.74, p = 0.001). Grade ≥ 3 toxicity rate with RT was 30% and associated with mucosal sub-site (OR 4.04, p = 0.03) and low BMI (<20 kg/m 2) [OR 6.04, p = .012]. Of the 149 patients, 59 were HIV-infected (40%). Most of the HIV-infected patients were on antiretroviral therapy (85%) and had suppressed viral loads (90% ≤400 copies/mL) with a median CD4 count of 400 cells/mm 3 (IQR: 237-584). HIV status was not associated with increased time to initiation of definitive RT (p = 0.440), decreased receipt of definitive RT (p = 0.137), worse survival (p = 0.606), or increased toxicity (p = 0.527). Despite access to government care, delayed presentation remains a significant issue for HNC patients in Botswana. A disproportionate number of patients with HNC are infected with HIV, but HIV status does not adversely impact survival or toxicity outcomes for these patients and should not preclude definitive management.