Evaluating the utility of computed tomography of the chest for gastric cancer staging Background: International guidelines recommend routine computed tomography (CT) of the chest for gastric cancer staging. In Asian countries, where the incidence of pulmonary metastases is less than 1%, some guidelines recommend chest CT only for gastroesophageal junction cancers. If the incidence of pulmonary metastases is also low in Canada, routine chest CT may not be beneficial. Methods: We performed a retrospective review of patients in northern Alberta with newly diagnosed gastric cancer from January 2010 to July 2016. The primary aim of the study was to determine the incidence of pulmonary metastases at the time of diagnosis in this population. A secondary aim was to identify potential predictors of pulmonary metastases. We reviewed CT reports for pulmonary metastases. Imaging data also included liver metastases, abdominal lymphadenopathy (> 1 cm), ascites and omental or peritoneal nodules. Other data recorded were age, sex, primary tumour location, histologic type and tumour grade. Results: Four hundred and sixty-two patients (311 men, 151 women) were included in the analysis. Pulmonary metastases were identified in 25 patients (5.4%) overall and in 11 of 299 patients (3.7%) whose primary cancer was not in the cardia. On univariate analysis the presence of liver metastases (odds ratio [OR] 7.72, 95% confidence interval [CI] 3.24-18.37, p < 0.001) and abdominal lymphadenopathy (OR 3.30, 95% CI 1.29-8.48, p = 0.01) was associated with an increased risk of pulmonary metastases. Liver metastases retained statistical significance on multivariate analysis (OR 6.17, 95% CI 2.53-15.03, p < 0.001). Conclusion: The incidence of pulmonary metastases at the time of gastric cancer diagnosis is higher in northern Alberta than previously reported in Asian studies. Abdominal lymphadenopathy and liver metastases confer an elevated risk of pulmonary metastases. Contexte : Les lignes directrices internationales recommandent une tomodensitométrie (TDM) thoracique de routine pour la stadification du cancer de l'estomac. Dans les pays asiatiques, où l'incidence des métastases pulmonaires est inférieure à 1 %, certaines lignes directrices recommandent la TMD thoracique seulement dans les cancers de la jonction gastro-oesophagienne. Si l'incidence des métastases pulmonaires est également faible au Canada, la TDM thoracique de routine pourrait ne pas être bénéfique. Méthodes : Nous avons procédé à une analyse rétrospective des patients du Nord de l'Alberta ayant reçu un diagnostic de cancer de l'estomac entre janvier 2010 et juillet 2016. L'objectif principal de l'étude était de déterminer l'incidence des métastases pulmonaires au moment du diagnostic chez cette population. Un objectif secondaire consistait à identifier les prédicteurs potentiels des métastases pulmonaires. Les rapports de TDM ont été passés en revue pour ce qui est des métastases pulmonaires. Les données provenant des épreuves d'imagerie incluaient aussi les métastases hépatique...