Esophageal Cancer Staging in Malawi: The Feasibility of Chest Radiography and Abdominal Ultrasound for Initial Evaluation.

Background: Esophageal cancer (EC) is the third leading cause of cancer-related morbidity and mortality in Malawi. Given limited imaging capacity and high costs, staging is not routinely performed. One proposed staging algorithm is to first evaluate for metastatic disease using low-cost chest radiography (CXR) and abdominal ultrasound (US) followed by confirmatory computerized tomography (CT) of the chest and abdomen if no metastases identified on initial screening. The feasibility of this approach is unknown for EC in sub-Saharan Africa and was studied in the context of a larger prospective observational cohort study of EC in Malawi. Methods: From 2021 to 2022, EC patients at Kamuzu Central Hospital in Lilongwe, Malawi enrolled in the Treatment Outcomes of Esophageal Cancer in Malawi (TOEC-M) study were recruited. Participants were scheduled for a CXR, US, and CT scan as part of this sub-study. Participant characteristics, completion rates, imaging findings, and barriers to completion were documented. For participants undergoing all three imaging studies, sensitivity and specificity were calculated. Results: Of 150 patients in TOEC-M, 67 (44.7%) enrolled in this sub-study. Mean age was 55.4 years and 50.8% were males. The majority had mid-esophageal (38 [56.7%]) squamous cell carcinomas (54 [80.6%]). CXR was completed in 54 (80.6%) study participants, US in 43 (64.2%), CT chest in 29 (43.3%), and CT abdomen in 24 (35.8%). Sixteen (23.9%) completed all studies and 4 (6.0%) did not undergo any imaging. Of the 63 patients that were imaged, metastatic disease was identified in 18 (28.6%) by any modality. Positive findings were identified on 3 (5.6%) CXRs, 4 (9.3%) US, and 18 (62.1%) CTs, most frequently liver masses followed by lung nodules and adenopathy. Barriers to imaging completion included participant functional status and scanner availability. Conclusions: As access to EC treatment modalities expands, feasible and accurate staging will become increasingly important to guide clinical management. Our results suggest that CXR and US may serve as useful initial tools for assessing metastatic disease. In patients not medically fit for oncologic treatment, positive findings on CXR and US may allow CT to be deferred. Barriers to implementation of a pragmatic stepwise staging algorithm identified in this study can inform future research and care for patients with EC in similar resource-limited settings.