Rural Versus Urban Colorectal and Lung Cancer Patients: Differences in Stage at Presentation

Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA.
Journal of the American College of Surgeons (Impact Factor: 5.12). 11/2007; 205(5):636-41. DOI: 10.1016/j.jamcollsurg.2007.04.043
Source: PubMed


Rural surgeons are often uneasy when their outcomes are compared with those of urban surgeons because they perceive that rural patients typically present with worse disease. Rural patients with cancer are commonly thought to present at a later stage of disease, although this is based largely on anecdotal evidence.
Retrospective, descriptive analysis of cancer stage at presentation of rural versus urban patients with two common cancers (lung, colorectal) using the Surveillance, Epidemiology, and End Results database from the National Cancer Institute. Rural versus urban designations were based on rural-urban continuum codes from the US Department of Agriculture. We constructed an ordinal logistic regression model to compare stage at presentation between rural and urban colorectal and lung cancer patients, while controlling for other factors that might be associated with late stage at presentation, including age, race, gender, marital status, income level, and level of education.
In univariate and multivariate analyses, patients with colorectal and lung cancer from rural areas were not more likely to present at later stage. The ordinal logistic regression model indicated that urban patients are more likely to present with late-stage colorectal and lung cancer, compared with rural patients (p < 0.001). For colon cancer, other factors notably associated with stage IV disease were low-income, African-American race, age younger than 65 years, divorce, male gender, and language isolation. For lung cancer, factors notably associated with stage IV disease were African-American race, divorce, male gender, and language isolation.
Urban rather than rural residence appears to be associated with later stages of lung and colorectal cancer at presentation. This finding is contrary to the common assumption that rural patients present at later stages of disease.

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    • "There is also interest in urban–rural differences and spatial variation in stage at diagnosis. For example a study using SEER data reports that urban as opposed to rural residence is associated with stage at diagnosis for lung and colorectal cancer [26] and there is also substantial geographic variation late stage breast and colorectal cancer diagnosis [27,28]. Access to care and the distribution of race-ethnic groups are associated with county level variation in stage at diagnosis identified in some of these studies, but considerable unaccounted for variation between counties remains. "
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    • "In Australia however rural inequalities in colorectal cancer survival have remained even after adjusting for spread of disease [6]. While it may be logical to suggest that rural people are diagnosed with more advanced cancers, a US study found that the opposite was true, in that urban patients were more likely to present with later stage colorectal cancer than rural patients [12]. So although disease stage could potentially explain a portion of the observed rural inequalities in colorectal cancer survival, it is unlikely to be the sole explanation. "
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