| Abstrakt: |
Background: A number of studies have been conducted to better understand the connection between travel distance and stage of cancer at diagnosis. However, these studies have had mixed results with some indicating that rural populations have a higher incidence of late-stage disease than do their urban counterparts, while others show the opposite effect. Still other studies find no difference when it comes to late-stage disease and the distance between a patient's home and the nearest health care facility. This study investigates the impact of travel distance on cancer stage and focuses on three common malignancies: breast, lung and colorectal. The hypothesis of this investigation is that patients who must travel greater distances to reach the Yankton Medical Clinic, a multidisciplinary clinic in rural southeastern South Dakota, have more advanced disease at presentation. Methods: Patient data including cancer type, year of diagnosis, home address and cancer stage at the time of diagnosis was obtained from the cancer registry maintained by the Yankton Medical Clinic for all patients who presented to the clinic with breast, colorectal or lung cancer between 1998 and 2008. Using Google Maps, the driving distance (miles) between patients' homes and the clinic was recorded. When exact street addresses were unavailable, distance to the clinic was calculated from the centroid of the zip code reported. For some analyses, patients were categorized as having either late-stage (stages III or IV) or early stage (stages 0, I or II) disease. Results: The average travel distance for patients diagnosed with late-stage disease was greater than that of patients diagnosed with earlier stages in all three malignancy types. In addition, the percentage of patients presenting with advanced stage breast or colorectal cancer was higher in patients who had to travel 15 or more miles to the clinic as compared to patients whose travel distance was less than 15 miles. This correlation was not seen in lung cancer patients at distances as low as 15 miles; however, when travel distance was 50 miles or greater, the association was evident. Finally, when all three cancer types were combined, a significant positive correlation between travel distance and stage I verses stage III was noted (p< 0.05). Upon further investigation it was found that the mean travel distance for stage III disease was greater than that for stage I disease in all three cancer types individually, and was significantly greater when the three malignancies were combined. However, the same effect was not seen when comparing stage I with stage IV disease. Conclusions: This study revealed that travel distance may pose a minor barrier in accessing care in rural southeastern South Dakota. When all three cancer types were combined, a significant relationship was seen between travel distance and stage III verses stage I disease with patients with stage III cancers traveling an appreciable farther distance than those with stage I disease. However, the fact that the same effect was not evident when comparing stage I with stage IV disease prompts further investigation. [ABSTRACT FROM AUTHOR] |
