Prevalence, Incidence and Outcomes of Colorectal Cancer in a VA Population

Abstract

Purpose: Colorectal cancer (CRC) is the third most common and second leading cause of cancer death, with prognosis affected by Stage at time of diagnosis. There remain greater than two thirds of patients (pts) in whom recommended screening colonoscopies (C-scopes) are not performed. This study reports the results of our 10 year screening & surveillance program at the Edward Hines VA Hospital. Methods: All 8,047 C-scopes performed between July 2001 and December 2011, associated pathology & pt outcomes were reviewed. Outcomes included overall distribution of CRC, prevalence, recurrence, incidence and mortality. Results: Of the 8,047 C-scopes performed, 470 pts with CRC were found for a prevalence of first C-scope CRC of 5.3%. The distribution of cancers according to indication were: Asymptomatic 32%, Anemia 22%, Symptoms 23%, OB positive 13% & Other 10%. Only a third of the pts presented with no symptoms vs. two thirds presented with a diagnostic indication such as positive fecal occult blood testing, anemia and/or symptoms such as blood in the stools or abdominal pain. The prevalence of CRC in the Asymptomatic group was 2.9%, with 85% having early stage (0,1,2) CRC. The prevalence of CRC in the Diagnostic group was 11.2%, with almost 40% having advanced Stage (3,4) CRC. Sixty-five percent of the Diagnostic group was dead at 6 months vs. only 30% of the Asymptomatic group (HR: 3.6; CI: 2.6-4.8). Regarding CRC Stage, the Advanced Stage (3,4) CRC pts had a predictably shorter survival with 50% Dead at 3 months vs. greater than 60% of the Early Stage CRC pts still Alive at 10 years (HR: 3.5; CI 2.5-4.9). Incident CRCs were discovered in 38 patients with initially benign C-scopes. Recurrent CRCs were discovered in29 patients after the treatment of the initial CRC. It is clear that waiting for symptoms to develop results in a prevalence four times greater and twice as fatal in the diagnostic group when compared to the asymptomatic group. Furthermore, once these diagnostic CRCs are found, pt survival is extremely poor. Conclusion: Based on our findings, it would take three times as many C-scopes to detect one incident CRC as one prevalent CRC, suggesting that resources should be directed at increased screening of Asymptomatic individuals. If survival from CRC is to improve, our data demonstrates that early detection is absolutely mandatory.Table: [1994] Prevalence of colorectal cancerTable: Cancers by stageFigure: [1994]