Disparities in receipt of adjuvant radiation therapy after breast-conserving surgery among the cancer-reporting regions of California.

BACKGROUND: Incidence and mortality of breast cancer vary according to demographic factors such as age, race/ethnicity, socioeconomic status (SES), and geographic region. This study assesses the variation of these factors in the use of adjuvant radiation therapy (RT) after breast-conserving surgery (BCS) among 8 regions of California. METHODS: The authors identified 85,574 cases of first primary female invasive breast cancer with complete data diagnosed between January 1, 2000 and December 31, 2007. Logistic regression was used to determine the association between race/ethnicity, age, SES, and receipt of RT after BCS within each of the regions of California. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed. RESULTS: Age was a significant predictor of receipt of RT after BCS in all regions. In Los Angeles (LA), lower SES was associated with decreasing odds of RT. Racial disparities were evident only in LA, where black (OR, 0.85; 95% CI, 0.74-0.97) and Hispanic (OR, 0.86; 95% CI, 0.78-0.96) women were about 15% less likely to receive RT than white women. CONCLUSIONS: Racial disparities in the receipt of RT after BCS exist only in LA, where African American and Hispanic women are less likely to receive this form of adjuvant treatment. Lower SES was also associated with a reduced likelihood of receipt of RT in LA. Women age 70 years and older are less likely to receive RT after BCS in all regions of California.

Quality of cancer registry data: findings from CDC-NPCR's Breast and Prostate Cancer Data Quality and Patterns of Care Study.

BACKGROUND: The Breast and Prostate Cancer Data Quality and Patterns of Care (POC-BP) Study enabled a reabstraction study of the quality of population-based, central cancer registry data on the characteristics and initial treatment of breast cancer in females and prostate cancer in the United States. METHODS: Stratified random samples of 9,103 female breast cancers and 8,995 prostate cancers were available for the analysis, using the independently reabstracted data as the gold standard to compute measurements of agreement. RESULTS: A slight majority (53% [8/15]) of the cancer site and treatment combinations showed kappa statistics > or = 0.60 and percent agreements, sensitivities, and predictive values positive > or = 80%: surgery and radiation for the 2 cancers, radiation completed and chemotherapy for breast cancer, and radiation modality and hormone therapy for prostate cancer. The qualities of the Collaborative Stage (CS) site-specific factors and derived variables for the 2 cancers were inconsistent, which confirmed the need to evaluate the recently-implemented CS algorithm. CONCLUSION: The data quality analysis from POC-BP underscores the importance of examining the quality of specific data variables by cancer site, thereby highlighting those variables for which data collection procedures could be improved.

Variation in breast cancer subtypes with age and race/ethnicity.

BACKGROUND: Both age and race have been identified as independent predictors of breast cancer subtype but the association of age with subtype within each race is not well understood. This study assesses the association of age with the eight breast cancer subtypes as defined by ER/PR/HER2 among white, African-American, Hispanic, and Asian/Pacific Islander women. METHODS: This study included 69,358 women with primary invasive breast cancer. Logistic regression was used to assess the association of age with each of the ER/PR/HER2 subtypes for each race adjusted for socioeconomic status, stage, grade, and tumor size. RESULTS: The odds of African-American women having a triple-negative tumor were not statistically significantly increased for women under 46 when compared to the African-American women aged 46-69 (OR=0.96; 95% CI=0.80-1.16). A similar pattern was observed for the ER-/PR-/HER2+ subtype. Hispanic women under age 46 (OR=0.83; 95% CI=0.71-0.97) and over age 70 (OR=0.71; 95% CI=0.57-0.89) were less likely to have the ER-/PR-/HER2+ subtype. Asian/Pacific Islander women under age 46 also had reduced odds (OR=0.67; 95% CI=0.55-0.82) of the ER-/PR-/HER2+ subtype. CONCLUSIONS: The ER/PR/HER2 subtypes vary with age and differences in this variation depend on race. It is important to define breast cancer using the ER/PR/HER2 subtype and the significance of age and race should not be overlooked.

Breast cancer subtypes as defined by the estrogen receptor (ER), progesterone receptor (PR), and the human epidermal growth factor receptor 2 (HER2) among women with invasive breast cancer in California, 1999-2004.

Breast cancer research examining either molecular profiles or biomarker subtypes has focused on the estrogen receptor negative/progesterone receptor negative/human epidermal growth factor receptor 2 negative (ER-/PR-/HER2-) and ER-/PR-/HER2+ subtypes. Less is known about the epidemiology or clinical outcome of the other subtypes. This study examines the eight combinations of ER/PR/HER2 in patients with invasive breast cancer. The 5-year relative survival and the distribution among demographic, socioeconomic, and tumor characteristics of each of the subtypes are examined. Using the California Cancer Registry, 61,309 women with primary invasive breast cancer were classified according to ER/PR/HER2 status. Five-year relative survival was computed for the eight subtypes. Bivariate analyses were used to assess the distribution of cases across all subtypes. Multivariate logistic regression was used to compute the adjusted odds of having one of the five subtypes with the best and worst survival. Survival varied from 96% (ER+/PR+/HER2-) to 76% (ER-/PR-/HER2+ and ER-/PR-/HER2-). The four subtypes with the poorest survival were all ER negative. Women who were younger than age 50, non-Hispanic black or Hispanic, of the lowest SES groups, and had stage IV tumors that were undifferentiated were overrepresented in ER-/PR-/HER2+ and triple negative (ER-/PR-/HER2-) subtypes. Asian Pacific Islanders had increased odds (OR = 1.41; 95% confidence interval [CI] = 1.26-1.57) of having the ER-/PR-/HER2+ subtype. Stage III tumors (OR = 1.25; 95% CI = 1.08-1.44) and stage IV tumors (OR = 1.58; 95% CI = 1.27-1.98) had higher odds than stage I tumors of being ER-/PR-/HER2+. Stage IV tumors (OR = 0.54; 95% CI = 0.44-0.67) strongly decreased the odds of the ER-/PR-/HER2- subtype. Poorly differentiated and undifferentiated tumors were over 20 times as likely as well-differentiated tumors of being ER-/PR-/HER2- or ER-/PR-/HER2+. There are considerable differences in survival, demographics, and tumor characteristics among the eight subtypes. We recommend reporting breast cancer as an ER/PR/HER2 subtype and precisely documenting demographic and tumor characteristics.

The impact of socioeconomic status on survival after cancer in the United States : findings from the National Program of Cancer Registries Patterns of Care Study.

BACKGROUND: Understanding the ways in which socioeconomic status (SES) affects mortality is important for defining strategies to eliminate the unequal burden of cancer by race and ethnicity in the United States. METHODS: Disease stage, treatment, and 5-year mortality rates were ascertained by reviewing medical records, and SES was determined by analyzing income and education at the census tract level for 4844 women with breast cancer, 4332 men with prostate cancer, and 4422 men and women with colorectal cancer who were diagnosed in 7 U.S. states in 1997. RESULTS: Low SES was associated with more advanced disease stage and with less aggressive treatment for all 3 cancers. The hazard ratio (HR) for 5-year all-cause mortality associated with low SES was elevated after a diagnosis of breast cancer when the analysis was adjusted for age (HR, 1.59; 95% confidence interval [CI], 1.35-1.87). Adjustment for mediating factors of race/ethnicity, comorbid conditions, cancer stage, and treatment reduced the association. The age-adjusted mortality risk associated with low SES was elevated after a diagnosis of prostate cancer (HR, 1.33; 95% CI, 1.13-1.57), and multivariate adjustments for mediating factors also reduced that association. There was less association between SES and mortality after a diagnosis of colorectal cancer. For all 3 cancer sites, low SES was a much stronger predictor of mortality among individuals aged <65 years and among individuals from racial/ethnic minority groups. CONCLUSIONS: The current results indicated that low SES is a risk factor for all-cause mortality after a diagnosis of cancer, largely because of a later stage at diagnosis and less aggressive treatment. These findings support the need to focus on SES as an underlying factor in cancer disparities by race and ethnicity.

The role of human epidermal growth factor receptor 2 in the survival of women with estrogen and progesterone receptor-negative, invasive breast cancer: the California Cancer Registry, 1999-2004.

BACKGROUND: Breast cancers that are negative for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) (triple negative [TN]) have been associated with high-grade histology, aggressive clinical behavior, and poor survival. It has been determined that breast cancers that are negative for ER and PR but positive for HER2 (double negative [DN]) share features with TN breast cancers. In this report, the authors quantified the contribution of HER2 as well as demographic and tumor characteristics to the survival of women with TN tumors, DN tumors, and other breast cancers (OBC). METHODS: In total, 61,309 women who were diagnosed with invasive breast cancer between 1999-2004 were identified in the California Cancer Registry. Demographic and tumor characteristics of women with TN tumors were compared with those from women with DN tumors and women with OBC. A compound proportional hazards regression analysis (PHPH) (a generalization of the Cox proportional hazards model) was used to model these characteristics. RESULTS: Women with TN tumors were younger, African American, Hispanic, and of lower socioeconomic status (SES), whereas women with DN tumors were slightly older; African American, and Asian/Pacific Islander. Women with TN and DN tumors presented with larger, higher grade, and higher stage than women with OBC. Survival among women with TN tumors was poorer compared with that among women with OBC but was nearly the same as that of women with DN tumors. Results of the regression analysis indicated that disease stage, tumor grade, SES, and race/ethnicity were significant risk factors for survival. Negative ER and PR status was associated with an increased risk of death. There was a small but significant difference in both long-term and short-term survival patients who had TN tumors compared with patients who had DN tumors. CONCLUSIONS: Patients with TN tumors shared many clinical, demographic, and tumor features and had survival that was very similar survival to that of patients with DN tumors, and survival for both groups contrasted greatly with survival for patients with OBC. Disease stage, tumor grade, SES, race/ethnicity, negative ER and PR status, rather than negative HER2 status, were risk factors for survival.

Descriptive analysis of estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and HER2-negative invasive breast cancer, the so-called triple-negative phenotype: a population-based study from the California cancer Registry.

BACKGROUND: Tumor markers are becoming increasingly important in breast cancer research because of their impact on prognosis, treatment, and survival, and because of their relation to breast cancer subtypes. The triple-negative phenotype is important because of its relation to the basal-like subtype of breast cancer. METHODS: Using the population-based California Cancer Registry data, we identified women diagnosed with triple-negative breast cancer between 1999 and 2003. We examined differences between triple-negative breast cancers compared with other breast cancers in relation to age, race/ethnicity, socioeconomic status (SES), stage at diagnosis, tumor grade, and relative survival. RESULTS: A total of 6370 women were identified as having triple-negative breast cancer and were compared with the 44,704 women with other breast cancers. Women with triple-negative breast cancers were significantly more likely to be under age 40 (odds ratio [OR], 1.53), and non-Hispanic black (OR, 1.77) or Hispanic (OR, 1.23). Regardless of stage at diagnosis, women with triple-negative breast cancers had poorer survival than those with other breast cancers, and non-Hispanic black women with late-stage triple-negative cancer had the poorest survival, with a 5-year relative survival of only 14%. CONCLUSIONS: Triple-negative breast cancers affect younger, non-Hispanic black and Hispanic women in areas of low SES. The tumors were diagnosed at later stage and were more aggressive, and these women had poorer survival regardless of stage. In addition, non-Hispanic black women with late-stage triple-negative breast cancer had the poorest survival of any comparable group.