CSP #707D - Colorectal Cancer-Risk Factors for Advanced Disease
Primary Objectives: To identify prognostic factors of late stage disease, particularly those
that are modifiable, that might explain the worsened prognosis with colorectal cancer among
veterans and that also might be responsive to intervention. Interventions directed at these
factors could lead to a decreased mortality among veterans.
Secondary Objectives: To compare outcomes among veterans with similar non-veterans who are
participating in the NCI-funded study: "Population Study of Colon Cancer in Blacks and
Whites" that is in-progress at the University of North Carolina at Chapel Hill.
Primary Outcomes: The primary outcomes are stage of disease and delay of diagnosis. Delay of
diagnosis is determined by length of time between symptom onset and medical consultation
(patient delay) and length of time between first seeking medical consultation and diagnosis
(physician or system delay). Stage of disease will be used as a proxy for survival.
Study Abstract: Colorectal cancer is the second leading cause of cancer death in the United
States each year. Approximately one million veterans aged 50 and older will develop
colorectal cancer over the remainder of their lives and nearly 433,000 will die from it.
Because most cancers are diagnosed after local or regional spread, nearly half of all
patients diagnosed with colorectal cancer will die. On a national basis, the relative five
year survival with colorectal cancer was estimated at approximately 40% among veterans,
substantially lower than SEER estimates in the general population of 61.7% (colon) and 59.3%
(rectum). Colorectal cancer is preventable through screening, however and, if diagnosed in
an early stage (Dukes' A and B), is curable.
This is the first study to examine factors that might explain the worsened prognosis for
veterans with colorectal cancer. If modifiable factors such as physician and patient delay
in diagnosis, or poverty, explain the increased mortality among veterans, educational
programs and interventions that improve the process of care associated with screening and
diagnosis can be instituted.
To-date, 659 subjects have been enrolled. Study participation involves obtaining
demographic, pathology and patient contact data on all colorectal cancer patients at the 14
participating sites and conducting a one-time telephone interview. Preliminary study data
suggests that most veterans with colorectal cancer present with evidence of regional or
distant spread of their colorectal cancer. No significant difference in stage at
presentation among veterans versus the population-based SEER patients is evident. Fewer
veterans present with localized disease (33% versus 40%) and, although not statistically
significant, could suggest a trend toward presentation at a more advanced stage.
Results of this study will provide a profile of patients at high-risk of presenting with
advanced colorectal cancer. This profile may be useful in designing patient and health care
system focused interventions to improve stage at diagnosis.
Final Results: Analyses are underway. A Final Report will be submitted to Durham ERIC within
90 days of study end date (03/31/02).
Dawn Provenzale, MD MS
Durham VA Medical Center HSR&D COE
United States: Federal Government
|Durham VA Medical Center HSR&D COE||Durham, North Carolina 27705|