Going against the tide: increasing incidence of colorectal cancer among Koreans, Filipinos, and South Asians in California, 1988-2007.

OBJECTIVE: Colorectal cancer has declined markedly in California for all major racial/ethnic groups, including Asian/Pacific Islanders as a whole. Analyzing cancer data for Asian/Pacific Islanders collectively masks important differences that exist between individual Asian subgroups. This study examines secular, sex-, age-, and socioeconomic-specific trends in colorectal cancer incidence among six Asian subgroups-Chinese, Japanese, Filipino, Korean, Vietnamese, and South Asian-to determine whether these groups experienced a decline in colorectal cancer incidence and to assess possible differences in colorectal cancer incidence trends among these groups. METHODS: Cases of invasive colorectal cancer diagnosed among Japanese, Chinese, Filipinos, Koreans, Vietnamese, and South Asians between 1988 and 2007 were identified using the California Cancer Registry database. Secular, sex-, age-, and socioeconomic-specific trends in the age-adjusted colorectal cancer incidence rates for each Asian subgroup were examined using joinpoint analysis to estimate the annual percent change (APC). RESULTS: Among males, Koreans (APC, 3.6 %) were the only group that experienced a significant increase in colorectal cancer incidence. Among females, Koreans (APC, 2.7 %), South Asians (APC, 2.8 %), and Filipinos (APC, 1.6 %) experienced significant increases. Stratification by age at diagnosis revealed that Korean males (APC, 3.4 %) and females (APC, 2.9 %) as well as Filipino females (APC, 1.8 %) aged 50 years and older experienced a significant increase in colorectal cancer incidence. Korean males aged less than 50 years (APC, 3.4 %) also experienced a significant increase. Japanese (APC, -1.2 %) and Chinese (APC, -1.6 %) males aged 50 years and older experienced a significant decrease in colorectal cancer incidence. Stratification by socioeconomic status (SES) revealed that Korean males (APC, 2.5 %) and females (APC, 2.9 %) as well as Filipino females (APC, 2.1 %) in the lowest SES category experienced a significant increase in colorectal cancer incidence. Korean males (APC, 5.2 %) and females (APC, 3.1 %) as well as Filipino males (APC, 1.5 %) in the highest SES category also experienced a significant increase. Japanese males (APC, -2.5 %) and females (APC, -2.0 %) as well as Chinese males (APC, -2.8 %) and females (APC, -2.9 %) in the lowest SES category experienced a significant decrease. Chinese males in the middle (APC, -3.4 %) and highest (APC, -3.5 %) SES categories also experienced significant decreases in colorectal cancer incidence. CONCLUSIONS: In contrast to the decreasing trends in colorectal cancer incidence reported among all major racial/ethnic groups including Asian/Pacific Islanders, colorectal cancer is actually increasing among some Asian subgroups in California including Korean males and females, as well as South Asian and Filipino females. Furthermore, the colorectal cancer incidence trends for these Asian subgroups differ with respect to age at diagnosis and socioeconomic status. These findings suggest that more efforts need to be made to target these populations with culturally sensitive cancer prevention and screening programs. More research is needed to examine the differences in the colorectal cancer burden among these populations.

Total and leisure-time walking among U.S. adults should every step count?

BACKGROUND: Although walking is a popular leisure-time activity, a substantial amount of total daily walking occurs in non-leisure contexts (i.e., occupation, transportation, and household work). Because non-leisure walking is not assessed by traditional leisure-time activity surveys, total walking among U.S. adults may be underestimated. This study describes walking estimates obtained from a measure of leisure-time activity and a specific measure of total walking in all contexts. METHODS: A national sample of adults (n=6626), selected by random-digit dialing, was surveyed between May 1999 and November 2000. Estimates of walking prevalence and of weekly time spent walking were examined from two separate modules: (1) an assessment restricted to leisure-time activity, and (2) an assessment of total walking. RESULTS: Walking prevalence based on the total walking module was nearly double that based on the leisure-time module (81% vs 43%, respectively). The median weekly minutes of walking also nearly doubled using the total walking module (239 vs 130 minutes, respectively). Among those with jobs involving substantial walking, median weekly walking minutes were more than three times greater with the total walking module (476 vs 130 minutes, respectively). CONCLUSIONS: U.S. adults, particularly those with jobs involving walking, do a substantial amount of walking not captured by traditional leisure-time activity surveys. This may affect the appropriate targeting of physical activity interventions, as well as the evaluation of the effectiveness of physical activity promotions and policies. However, further characterization of non-leisure walking is needed to determine its contribution to health and meeting physical activity guidelines.

Effect of misclassified underlying cause of death on survival estimates of colon and rectal cancer.

Inaccurate coding of patients' Underlying Cause of Death (UCOD) has constrained cause-specific survival estimates for colon and rectal cancers. Using California data from the Accuracy of Cancer Mortality study, we compared the cancer site data from the California Cancer Registry (CCR) with UCODs reported on death certificates and reclassified the UCODs based on cancer registry data when they disagreed. We then calculated 1-, 3-, 5-, and 10-year cause-specific survival for colon and rectal cancers separately, before and after the reclassification. Records from 26 312 colon and 10 687 rectal cancer patients were examined. UCOD records disagreed with CCR records for 700 (6%) of 11 404 colon cancer deaths and with 1958 (39%) of 5011 rectal cancer deaths, and 82% of the misclassified rectal cancer deaths were coded as colon cancer deaths in the UCOD. Reclassification decreased cause-specific survival for both colon and rectal cancers, but the impact was more pronounced for rectal cancer (eg, 5-year cause-specific survival of colon cancer decreased by 2.8% and of rectal cancer decreased by 20.0% relative to previous estimates; absolute rates changed from 65.4% to 63.6%, and 81.2% to 64.9%, respectively, after reclassification). Interchangeable use of the terms colon cancer and colorectal cancer is likely to be one of the reasons for UCOD misclassification. Educational measures could improve the accuracy of UCOD for colon and rectal cancer deaths.

Cervical cancer incidence, mortality, and survival among Asian subgroups in California, 1990-2004.

BACKGROUND: Aggregated cancer statistics for Asians mask important differences in cancer burden among Asian subgroups. The purpose of this study was to describe the relative patterns of cervical cancer incidence, mortality, and survival among Chinese, Filipino, Japanese, Korean, South Asian, and Vietnamese women in California, using data from the California Cancer Registry. METHODS: All cervical cancer cases diagnosed among the 6 subgroups and non-Hispanic whites (NHW) from 1990 to 2004 were identified and used to calculate incidence and mortality rates and trends. The Kaplan-Meier method was used to calculate 5- and 10-year survival probabilities by subgroup, and Cox proportional hazards methodology was used to calculate survival differences adjusted for race and ethnicity, age, stage at diagnosis, socioeconomic status, and treatment factors. RESULTS: Vietnamese and Korean women experienced greater cervical cancer incidence and mortality than NHW women, whereas rates among Chinese, Japanese, and South Asians were comparable or lower. Five-year unadjusted survival probabilities were greatest for South Asians (86%) and Koreans (86%), followed by Vietnamese (82%), Chinese (79%), and Filipinos (79%), as compared with NHW (78%) and Japanese (72%). The adjusted risk of cervical cancer death was significantly lower for South Asians, Koreans, Vietnamese, and Filipinos than for NHW women, but not for Chinese and Japanese. CONCLUSIONS: Cervical cancer incidence rates vary substantially across the major Asian subgroups. Despite higher incidence and mortality rates compared with NHW women, Vietnamese, Koreans, and Filipinos have better survival outcomes. Further studies are needed to examine the factors behind these survival differences.

Colorectal cancer stage at diagnosis by socioeconomic and urban/rural status in California, 1988-2000.

BACKGROUND: Rural residence has been associated with increased risk of late stage cancer diagnosis, but it is unknown if this is related to lower socioeconomic status (SES) of rural residents or to other factors. This study examined the impacts of SES and urban/rural status on colorectal cancer (CRC) stage at diagnosis in California. METHODS: Cases of CRC among persons >or=50 years of age diagnosed from 1988-2000 were obtained from the California Cancer Registry. A composite census based SES measure was used in the analysis, and the RUCA (Rural Urban Commuting Areas) classification scheme was used to categorize the residence at diagnosis as urban, large town, or small town. Multivariate logistic regression was used to examine the association between SES, urban/rural status, and late stage at diagnosis. RESULTS: In multivariate models, SES had the strongest association with stage at diagnosis among individuals living in urban areas. As SES level increased, odds of late stage at diagnosis decreased. Individuals in the highest SES category had lower odds of being diagnosed at late stage when compared with those in the lowest SES category (O.R. = 0.91, 95% C.I. = 0.87, 0.94). For individuals who lived in large towns and small rural towns, SES was not significantly associated with stage at diagnosis. We found no significant differences in stage at diagnosis by urban/rural status within SES categories. CONCLUSIONS: These data suggest that the relationship between SES and the risk of late stage colorectal cancer varies among rural and urban populations. Further research into the factors that influence access to and utilization of colorectal cancer screening in rural areas is needed.

Use of the spatial scan statistic to identify geographic variations in late stage colorectal cancer in California (United States).

OBJECTIVES: To identify geographic variations in colorectal cancer by stage at diagnosis in California using a descriptive analysis coupled with a spatial analysis and to discuss methodological considerations concerning the spatial statistical method. METHODS: We analyzed 59,076 colorectal cancer cases diagnosed in California from 1996 to 2000 by logistic regression and by a spatial scan statistic to identify areas with a higher and lower relative risk of late-stage colorectal cancer. RESULTS: In California, 57% of overall cases of colorectal cancer were diagnosed at a late stage. Californians diagnosed with late-stage colorectal cancer were more likely to be Hispanic and living in areas of lower socioeconomic status. The spatial scan identified two areas where the observed number of late-stage cancer was different than the number expected from the distribution in the rest of the state. CONCLUSIONS: Spatial scan analyses can complement descriptive statistics, but results must be interpreted with consideration of factors that affect the ability to detect meaningful differences such as the number of events observed, accuracy in geocoding rural versus urban addresses, and the difficulty of adjusting for covariates.

Stage of breast cancer diagnosis among medically underserved women in California receiving mammography through a state screening program.

OBJECTIVE: This study describes breast cancer stage at diagnosis among California women receiving mammograms through a state-administered screening program in comparison to other California women. METHOD: Linked data from California-administered screening programs and the California Cancer Registry were used to identify participants diagnosed with breast cancer between 1994 and 2000. Logistic regression was used to compare the adjusted likelihood of late stage disease among program participants (categorized into four subgroups based on the timing and frequency of mammograms) to non-participants in California diagnosed during the same time period. RESULTS: Program participants were significantly more likely than non-participants to be diagnosed at late stage (adjusted OR 1.2; 95% CI 1.1, 1.3), with the highest risk occurring among those diagnosed 0-1 months after initial mammogram (adjusted OR 1.8; 95% CI 1.6, 2.1). The stage distribution among regularly screened participants was similar to non-participants (adjusted OR of late stage disease 0.9; 95% CI 0.7, 1.1). CONCLUSIONS: Although program participants were more likely to be diagnosed at late stage than non-participants, their stage distribution was distinctly different according to their pattern of mammography utilization. This likely reflects differential utilization of program diagnostic and screening services, which should be taken into account in program evaluation.