Changes in the Number of Gastrointestinal Cancers and Stage at Diagnosis with COVID-19 Pandemic in Japan: A Multicenter Cohort Study

Abstract

This retrospective cohort study compared the number of newly diagnosed patients, stage at diagnosis, and detection process of gastrointestinal cancers based on hospital-based cancer registry data at two tertiary Japanese hospitals. The pre-COVID-19 period was from January 2017 to February 2020, with phase 1 (midst of COVID-19 pandemic) from March to December 2020 and phase 2 (the transition period to the “new normal”) from January to December 2021. Each month, the number of patients diagnosed with esophageal, gastric, colorectal, pancreatic, liver, and biliary tract cancers were aggregated, classified by stage and detection process, and compared, including a total of 6453 patients. The number of colorectal Stage 0-II patients decreased significantly in phase 1 and increased in phase 2. The total number of colorectal cancer patients returned to pre-COVID-19 levels (mean monthly patients [SD]: 41.61 [6.81] vs. 36.00 [6.72] vs. 46.00 [11.32]). The number of patients with gastric cancer Stage I significantly decreased in phase 2 following phase 1. The number of gastric cancer patients decreased significantly from pre-COVID-19 levels (30.63 [6.62] vs. 22.40 [5.85] vs. 24.50 [4.15]). During phase 2, the number of patients diagnosed after screening with colorectal cancer increased significantly, whereas that with gastric cancer remained considerably lower. The number of Stage III colorectal and gastric cancer patients increased significantly from the pre-COVID-19 levels. Thus, gastric cancer may not be optimally screened during phases 1 and 2. There was a significant increase in patients with Stage III colorectal and gastric cancers from the pre-COVID-19 period; hence, the stage at diagnosis may have progressed.

Trends of Early Helicobacter pylori-Uninfected Gastric Cancer in an Aging Regional Area

“…Sixth, although not observed in the Kagoshima Prefecture data, the decline in the number of cases in 2020 and 2021 in the NDB data may have been influenced by the COVID-19 pandemic. There have been reports of a decrease in the diagnosis and treatment of curable early-stage GC, as well as a decrease in the number of surgeries, following the COVID-19 pandemic [ 38 , 39 , 40 ]. While this observation in the NDB data does not affect the primary endpoint of the current study, further verification of the discrepancy with the data from Kagoshima Prefecture is needed.…”

Influence of the COVID-19 Pandemic on Patients with Rectal Cancer

“…The COVID-19 pandemic imposed numerous restrictions on both the medical and private sectors, causing widespread concerns among the population [ 1 ]. A noticeable consequence was delayed diagnoses leading to more advanced tumor stages across various cancer types [ 41 , 42 ]. While the pandemic led to a significant impact on colon cancer patients [ 24 ], the influence on rectal cancer seems comparatively less pronounced.…”

Trends in Gastrointestinal Infections during the COVID-19 Pandemic and Concerns of Post-Pandemic Resurgence in Japan

“…On the other hand, for diseases other than infectious diseases, such as cancer [21], the number of diagnoses also declined markedly during the COVID-19 pandemic, but has recovered since the end of the pandemic due to the resumption of medical services and changes in patient visitation behavior. It is therefore important to focus on the study of the impact of COVID-19 not only on infectious diseases but also on other diseases, because these findings may become useful in predicting future pandemics.…”