Colorectal Cancer T Stage, Size at Diagnosis and Presentation 2017-2023: An Analysis Using VA Data.
Academic Article
Overview
abstract
OBJECTIVES: Colorectal cancer is the fourth most common cancer in the U.S., and early detection decreases mortality. We evaluated recent trends in colon cancer incidence and changes in rates of presentation with bowel obstruction before and during the COVID-19 pandemic. METHODS: Longitudinal study of U.S. Veterans from 2017-2023. The primary exposure was time-period: pre-pandemic (01/01/2017-02/29/2020) compared to pandemic (03/01/2020-10/31/2023). The primary outcome was new colon cancer diagnoses. We compared observed to expected diagnoses during the pandemic period. Malignant bowel obstruction at index diagnosis date, AJCC tumor stage, and tumor size at time of diagnosis were compared by period using standardized differences and bootstrapped confidence intervals. RESULTS: There were 22,256 new colon cancer diagnoses made in the VA: mean age 71±11 years old, 96% male, and 72% White. Comparing the pandemic to pre-pandemic periods, the proportion of tumors >4cm increased from 48.9% to 57.3% and the proportion with malignant bowel obstruction at presentation doubled from 2.7% to 5.3%. An estimated 619 cases were 'missed' during the pandemic: they were expected but not observed diagnoses. There were greater observed than expected large cancers, and fewer observed than expected small cancers during the pandemic according to forecast analyses. CONCLUSIONS: Interruptions in care following the onset of the COVID-19 pandemic had measurable consequences among U.S. Veterans through the end of 2023. Among those diagnosed, median size was larger and more presented with bowel obstruction. This may be because decreased screening activity combined with lower healthcare utilization changed the distribution of cancer size at diagnosis to be larger - underlining the importance of encouraging engagement or re-engagement of Veterans in colorectal cancer screening.
