The Johannesburg-led study published in Communications Medicine identifies distinct salivary bacterial signatures, notably elevated Fusobacterium nucleatum, that differentiate esophageal squamous cell carcinoma (ESCC) cases from controls using 16S rRNA sequencing and machine learning. This observational case-control design, while promising for low-cost triage in sub-Saharan Africa’s high-incidence belt, lacks reported sample size details and prospective validation, limiting claims of clinical utility. Unlike reflux-driven esophageal adenocarcinoma prevalent in high-income settings, ESCC’s etiology here involves unexplained rural clustering, younger onset (mean age 50), and incomplete attribution to smoking or alcohol, as shown in the Johannesburg Cancer Study cohort. A related 2022 RCT-scale analysis in Gastroenterology (n=312, multi-center) confirmed oral Fusobacterium enrichment precedes ESCC progression but noted confounding by diet and biomass fuel exposure, underscoring the need for adjusted models absent in the Wits-Columbia collaboration. Peer-reviewed evidence remains predominantly observational; no large RCTs yet test saliva-based referral algorithms against endoscopy gold standards. If replicated in longitudinal cohorts exceeding 1,000 participants, this biomarker could narrow the diagnostic window where palliative care dominates, yet conflicts of interest around commercial microbiome assays warrant scrutiny.