摘要：Objectives. We examined geographic differences and trends in incidence and mortality of ovarian and uterine cancer in American Indian/Alaska Native (AI/AN) women. Methods. We linked mortality data (1990–2009) and incidence data (1999–2009) to Indian Health Service (IHS) records. Death (and incidence) rates for ovarian and uterine cancer were examined for AI/AN and White women; Hispanics were excluded. Analyses focused on Contract Health Service Delivery Area (CHSDA) counties. Results. AI/AN and White women had similar ovarian and uterine cancer death rates. Ovarian and uterine cancer incidence and death rates were higher for AI/ANs residing in CHSDA counties than for all US counties. We also observed geographic differences, regardless of CHSDA residence, in ovarian and uterine cancer incidence and death rates in AI/AN women by IHS region; Pacific Coast and Southern Plains women had higher ovarian cancer death rates and Northern Plains women had higher uterine cancer death rates. Conclusions. Regional differences in the incidence and mortality of ovarian and uterine cancers among AI/AN women in the United States were significant. More research among correctly classified AI/AN women is needed to understand these differences. Ovarian and uterine cancers are among the top 10 leading causes of cancer deaths and incidence among US women. In 2009, 14 436 deaths resulted from ovarian cancer and 7713 deaths resulted from cancer of the uterine corpus. Additionally, 20 460 new cases of ovarian cancer and 44 192 cases of cancer of the uterine corpus occurred in the United States, accounting for 3% and 6% of all cancer among women, respectively. 1 Incidence rates (IRs) for ovarian cancer decreased from 2005 to 2009, and although ovarian cancer still causes more deaths than any other cancer of the female reproductive system, the average death rate for ovarian cancer also decreased by 2.0% per year during this time period. 1 Alternatively, both death rates and IRs increased for uterine cancer among all women from 2005 to 2009. 2 Cancer, including ovarian and uterine cancer, is a major public health concern in American Indian/Alaska Native (AI/AN) communities. 3 Studies examining cancer incidence patterns among AI/AN populations have generally been limited to restricted time intervals or selected geographic regions. 4–12 Additionally, misclassification of AI/AN race in central cancer registry data and on death certificates has led to underestimation of cancer burden in these populations. 13,14 Previous studies have documented misclassification of AI/AN persons as another race in central cancer registry data and that the extent of variation varies by registry. 15–17 Arias et al. 14 reported that approximately 42% of AI/AN decedents were misclassified as White on death certificates. Cancer information for AI/AN populations is known to be incomplete because the racial/ethnic status of many of these individuals is not correctly identified in medical and death records. 18 Although linkages between central cancer registries and Indian Health Service (IHS) records have improved incidence estimates for AI/AN populations, 17,19 most estimates of cancer mortality currently available likely underestimate death rates in this population. According to a study of data from the Alaska Tumor Registry, Alaska Native women have exhibited some of the highest IRs of cancer overall and different patterns of site-specific incidence compared with other US populations. 20 Reportedly, trends in cancer IRs among AI/AN people have been stable or decreasing, whereas cancer death rates have increased. 20 Although differences in overall cancer rates have been observed, 21 little is known about the rates of cancer of the uterine corpus and ovary in AI/AN populations. This article provides a detailed overview of the burden of cancer of the ovaries and uterine corpus among AI/AN populations. The main objective of this study was to improve our understanding of uterine and ovarian cancer incidence, stage at diagnosis, and mortality in AI/AN women relative to White women by minimizing the effect of racial misclassification in the cancer data. The secondary objective is to examine geographic differences and trends in incidence and mortality of ovarian and uterine cancer in AI/AN populations.
