Small-bowel cancer is uncommon and, accordingly, little is known about the epidemiology of this malignancy, especially by race and subtype.
The objective of this analysis was to describe the distribution of small-bowel cancer in the United States by demographic, pathological, and clinical features.
This study was retrospective in design.
Data from 26 population-based cancer registries in the United States from 1995 to 2008 were used.
Patients diagnosed with small-bowel cancer (topography codes C17.0–17.3 and C17.8–17.9) were included.
The primary outcomes measured were race- and histology-specific incidence (age-adjusted rate trends and age-specific rates) of small-bowel cancer.
A total of 56,223 men and women diagnosed with small-bowel cancer were identified. The overall age-adjusted incidence rates for small-bowel cancer were 26.1 in men and 17.7 in women. Neuroendocrine tumors were the most common histological types of small-bowel cancer in men and women, followed by carcinoma, lymphoma, and sarcoma. In comparison with whites, the rate of small-bowel cancer was 42% greater in black men, 46% greater in black women, 34% lower in Asian-Pacific Islander men, and 37% lower in Asian-Pacific Islander women. Rates of small-bowel cancer were 24% lower in Hispanic men and 15% lower in Hispanic women than rates in non-Hispanics. The excess of small-bowel cancer in blacks and the deficit in Asian-Pacific Islanders were attributable mainly to the incidence of adenocarcinoma and carcinoid tumors. The incidence of GI stromal tumor was significantly higher among Asian-Pacific Islanders.
This is one of the largest studies of small-bowel cancer to date. These cancer registry data showed substantial racial and ethnic variation in the incidence of histological subtypes of small-bowel malignancy that suggest possible etiologic diversity and/or disparities in detection.
Epidemiology Program, Cancer Center, University of Hawaii, Honolulu, Hawaii
Funding/Support: This work was supported by the Centers for Disease Control and Prevention under cooperative agreement U75/CCU515998 to the North American Association of Central Cancer Registries and by the National Cancer Institute’s Surveillance, Epidemiology, and End-Results Program under contract N01-CN-67001 from the National Institutes of Health, Department of Health and Human Services.
Financial Disclosure: None reported.
Correspondence: Marc T. Goodman, Ph.D., Epidemiology Program, Cancer Center, University of Hawaii, 1236 Lauhala St, Honolulu, HI 96813. E-mail: firstname.lastname@example.org