BackgroundKaposi sarcoma is one of the most prevalent HIV-associated malignancies in sub-Saharan Africa and is often diagnosed at advanced stage of disease. Only 50% of KS patients who qualify for chemotherapy receive it and adherence is sub-optimal.Methods57 patients > 18 years with newly diagnosed KS within the AMPATH clinic network in Western Kenya were purposively selected to participate in semi-structured interviews stratified by whether they had completed, partially completed, or not completed chemotherapy for advanced stage KS. We based the interview guide and coding framework on the situated Information, Motivation, Behavioral Skills (sIMB) framework, in which the core patient centered IMB constructs are situated into the socioecological context of receiving care.ResultsOf the 57 participants, the median age was 37 (IQR 32-41) and the majority were male (68%). Notable barriers to chemotherapy initiation and adherence included lack of financial means, difficulty with convenience of appointments such as distance to facility, appointment times, long lines, limited appointments, intrapersonal barriers such as fear or hopelessness, and lack of proper or sufficient information about chemotherapy. Factors that facilitated chemotherapy initiation and adherence included health literacy, motivation to treat symptoms, improvement on chemotherapy, prioritization of self-care, resilience while experiencing side effects, ability to carry out behavioral skills, obtaining national health insurance, and free chemotherapy.ConclusionOur findings about the barriers and facilitators to chemotherapy initiation and adherence for KS in Western Kenya support further work that promotes public health campaigns with reliable cancer and chemotherapy information, improves education about the chemotherapy process and side effects, increases oncology service ability, supports enrollment in national health insurance, and increases incorporation of chronic disease care into existing HIV treatment networks.