A retrospective review of patients with Kaposi's sarcoma in Botswana

Background: Despite widespread antiretroviral coverage in Botswana, Kaposi's sarcoma (KS) remains among the most common malignancies. To date, adult KS in Botswana is not well characterized. The diagnosis relies on clinical suspicion that is often confirmed by histopathology given the implications of treatment; however, this poses a significant resource burden.

Methods: We conducted a retrospective review of the cohort of patients biopsied for possible KS at Princess Marina Hospital, the main dermatology referral site in Botswana, from September 2008 through June 2015 to describe the demographics, human immunodeficiency virus (HIV) characteristics, and clinical presentations of these patients. Histopathologic diagnoses were reviewed, and positive predictive value (PPV) was used to characterize the accuracy of clinical suspicion of KS.

Results: A total of 441 patients received 450 biopsies where KS was on the differential diagnosis, and 239 patients (54%) were ultimately diagnosed with KS. The KS cohort was more likely to be male (58% vs. 37%, P < 0.001), HIV positive (94% vs. 85%, P < 0.05), and have lower CD4 counts at the time of biopsy (274 cells/μl vs. 362 cells/μl, P < 0.05). The PPV of clinical suspicion of KS was 58%. When KS was not histopathologically diagnosed, clinically benign diseases were found in 17%, medically significant conditions requiring alternative therapies in 78%, and life-threatening diseases in 5%.

Discussion: Our study reinforces the risk factors in development of KS. The poor PPV supports the important role of histology in KS diagnosis to both ensure appropriate treatment and prevent overtreatment. Improved accessibility to biopsy and augmentation of local dermatopathologic services would likely improve diagnostic accuracy and treatment.