CT Imaging as a Single Modality for Clinical Staging of Gastric Cancer in Limited Resource Centers: A Retrospective Pilot Study.

Abstract

Gastric cancer disproportionately impacts populations in resource-limited settings. Within a safety-net network, we assessed the utility of computed tomography (CT) as a single staging modality. We utilized a clinical database of gastric cancer patients treated within the Los Angeles County safety-net hospital system from 2016 to 2023 in conjunction with retrospective imaging review by certified radiologists. We assessed agreement between clinical and pathological staging for patients who underwent curative gastrectomy using the Kappa coefficient. Of 107 patients with available CT imaging, 43.9% (n = 47) were staged with CT as a single modality. Most tumors displayed infiltrating (75%) or diffuse (28%) morphology, 41% displayed adequate gastric distention and regional lymphadenopathy was common (68%). Twenty-nine patients underwent curative gastrectomy. Overall agreement was minimal (κ = 0.29, 95% CI [0.071-0.51], p = 0.022), weak for T3/T4 tumors (κ = 0.50, 95% CI [0.17-0.82], p < 0.01), and weak for Hispanic/Latino patients (κ = 0.47, 95% CI [0.19-0.76], p < 0.01). There was minimal agreement between clinical and pathologic staging when assessing clinical stage by CT imaging alone, suggesting that CT is not adequate as a single modality staging tool. While every effort should be made to obtain multimodal staging, larger studies are warranted to improve CT imaging protocols for staging in resource-limited settings.