Gastrointestinal Cancer Stage at Diagnosis Before and During the COVID-19 Pandemic in Japan.

Importance: The COVID-19 pandemic has delayed medical consultations, possibly leading to the diagnosis of gastrointestinal cancer at advanced stages. Objective: To evaluate stage at diagnosis among patients with gastrointestinal cancer in Japan before and during the COVID-19 pandemic. Design, Setting, and Participants: This retrospective cohort study included patients in a hospital-based cancer registry who were diagnosed with gastrointestinal cancer (ie, esophageal, gastric, colorectal, pancreatic, liver, and biliary tract cancers) between January 2016 and December 2020 at 2 tertiary Japanese hospitals. Exposures: The pre-COVID-19 period was defined as January 2017 to February 2020, and the COVID-19 period was defined as March 2020 to December 2020. Main Outcome and Measure: Monthly numbers of patients with newly diagnosed cancer were aggregated, classified by stage, and compared. Results: The study evaluated 5167 patients, including 4218 patients (2825 [67.0%] men; mean [SD] age, 71.3 [10.9] years) in the pre-COVID-19 period and 949 patients (607 [64.0%] men; mean [SD] age, 71.8 [10.7] years) in the COVID-19 period. Comparing the pre-COVID-19 period with the COVID-19 period, significant decreases were observed in the mean (SD) number of patients with newly diagnosed gastric cancer (30.63 [6.62] patients/month vs 22.40 [5.85] patients/month; -26.87% change; P < .001) and colorectal cancer (41.61 [6.81] patients/month vs 36.00 [6.72] patients/month; -13.47% change; P = .03). Significant decreases were also observed in the mean (SD) number of cases of stage I gastric cancer (21.55 [5.66] cases/month vs 13.90 [5.99] cases/month; -35.51% change; P < .001), stage 0 colorectal cancer (10.58 [3.36] cases/month vs 7.10 [4.10] cases/month; -32.89% change; P = .008), and stage I colorectal cancer (10.16 [3.14] cases/month vs 6.70 [2.91] cases/month; -34.04% change; P = .003). No significant increases were observed for esophageal, gastric, pancreatic, liver, or biliary tract cancers. A significant decrease was observed in the mean (SD) number of cases per month of stage II colorectal cancer (7.42 [3.06] cases/month vs 4.80 [1.75] cases/month; -35.32% change; P = .01); a significant increase was observed for the mean (SD) number of cases per month of stage III colorectal cancer (7.18 [2.85] cases/month vs 12.10 [2.42] cases/month; 68.42% change; P < .001). Conclusions and Relevance: In this cohort study of patients in a hospital-based cancer registry form Japan, significantly fewer patients were diagnosed with stage I gastric and colorectal cancers during the COVID-19 pandemic. Thus, the number of screening-detected cancers might have decreased, and colorectal cancer may have been diagnosed at more advanced stages.

Severe acute respiratory syndrome coronavirus 2 prevalence in saliva and gastric and intestinal fluid in patients undergoing gastrointestinal endoscopy in coronavirus disease 2019 endemic areas: Prospective cross-sectional study in Japan.

OBJECTIVES: Gastrointestinal endoscopy (GIE) is useful for the early detection and treatment of many diseases; however, GIE is considered a high-risk procedure in the coronavirus disease 2019 (COVID-19) pandemic era. This study aimed to explore the rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positivity in saliva and gastrointestinal fluids to which endoscopy medical staff are exposed. METHODS: The study was a single-center cross-sectional study. From June 1 to July 31, 2020, all patients who underwent GIE at Yokohama City University Hospital were registered. All patients provided 3 mL of saliva. For upper GIE, 10 mL of gastric fluid was collected through the endoscope. For lower GIE, 10 mL of intestinal fluid was collected through the endoscope. The primary outcome was the positive rate of SARS-CoV-2 in saliva and gastrointestinal fluids. We also analyzed serum-specific antibodies for SARS-CoV-2 and patients' background information. RESULTS: A total of 783 samples (560 upper GIE and 223 lower GIE samples) were analyzed. Polymerase chain reaction (PCR) on saliva samples did not show any positive results in either upper or lower GIE samples. However, 2.0% (16/783) of gastrointestinal fluid samples tested positive for SARS-CoV-2. No significant differences in age, sex, purpose of endoscopy, medication, or rate of antibody test positivity were found between PCR positive and PCR negative cases. CONCLUSIONS: Asymptomatic patients, even those with no detectable virus in their saliva, had SARS-CoV-2 in their gastrointestinal tract. Endoscopy medical staff should be aware of infection when performing procedures. The study was registered as UMIN000040587.