Rapid case ascertainment (RCA) refers to the expeditious and detailed examination of patients with a potentially rapidly fatal disease shortly after diagnosis. RCA is frequently performed in resource-rich settings to facilitate cancer research. Despite its utility, RCA is rarely implemented in resource-limited settings and has not been performed for malignancies. One cancer and context that would benefit from RCA in a resource-limited setting is HIV-related Kaposi sarcoma (KS) in sub-Saharan Africa.
To determine the feasibility of RCA for KS, we searched for all potential newly diagnosed KS among HIV-infected adults attending three community-based facilities in Uganda and Kenya. Searching involved querying of electronic medical records, pathology record review, and notification by clinicians. Upon identification, a team verified eligibility and attempted to locate patients to perform RCA, which included epidemiologic, clinical and laboratory measurements.
We identified 593 patients with suspected new KS. Of the 593, 171 were ineligible, mainly because biopsy failed to confirm KS (65%) or KS was not new (30%). Among the 422 remaining, RCA was performed within 1 month for 56% of patients and within 3 months for 65% (95% confidence interval: 59 to 70%). Reasons for not performing RCA included intervening death (47%), inability to contact (44%), refusal/unsuitable to consent (8.3%), and patient re-location (0.7%).
We found that RCA ― an important tool for cancer research in resource-rich settings ― is feasible for the investigation of community-representative KS in East Africa. Feasibility of RCA for KS suggests feasibility for other cancers in Africa.
Rapid case ascertainment (RCA) refers to the thorough research-level evaluation of a patient shortly following diagnosis of a particular condition. While RCA can be performed for any disease, it has mainly been used to evaluate potentially rapidly progressive/fatal disease. This is because RCA allows one to perform detailed clinical and laboratory measurements prior to either the demise of the patient or before he/she experiences either a spontaneous or treatment-induced change from his/her condition at time of diagnosis [ , ]. As such, RCA measurements are critical in facilitating research regarding stage of disease at diagnosis (i.e., a key metric for the effectiveness of early detection efforts), determinants of disease occurrence (i.e., etiology), and determinants of prognosis [ ]. Since its origin [ , , ], RCA has predominantly been performed in resource-rich settings, where it is mostly used to study cancer (e.g., pancreatic [ ]). Despite its potential utility, RCA has rarely been used in resource-limited settings, with the exception of selected infectious diseases [ ] in which its utility is to decrease spread. To our knowledge, RCA has not been used to study cancer in resource-limited settings, and there are reasons to believe that it may not be as successful as in resource-rich regions. These include delays in return of pathology results; lack of access to therapy and hence rapid fatality; difficulties in reaching patients due to incomplete phone and residential locator information; and potential hesitancy among gravely ill patients to consent for research.
One cancer and resource-limited context in which findings from RCA would be useful to inform policy and facilitate research is HIV-related Kaposi sarcoma (KS) in sub-Saharan Africa. In this region, even with increased antiretroviral therapy (ART) availability for treatment of HIV infection, KS is the fifth most common cancer in all adults [ ]. In addition to being common, survival following KS diagnosis in Africa is also poor; one-year mortality is between 20 to 40% [ ]. Advanced stage of KS at time of diagnosis is often hypothesized to explain this high mortality, but population-level description of KS stage at diagnosis is lacking. Increasing availability of ART in Africa [ ], however, suggests that the epidemiology of KS may change as it has in resource-rich settings [ ]. Wider use of ART may change both stage of KS at diagnosis and survival. Yet, if KS continues to occur despite ART, this begs questions as to why. A thorough evaluation of a community-representative sample of patients with KS in Africa as soon as they are diagnosed ― through RCA ― would facilitate research on all these questions.
To evaluate the feasibility of performing RCA for cancer in a resource-limited setting, we endeavored to perform RCA among a community-representative sample of new diagnoses of KS in East Africa. We describe the methods required to establish RCA, the successes, and limitations of the process.