Breast-Conserving Tx Keeps Growing, but Disparities Persist

Use of BCT for early breast cancer often hinges on socioeconomic factors

By Charles Bankhead

Dallas, TX | Posted April 11, 2016

Breast-conserving therapy (BCT) continued a slow evolution into the predominant surgical approach for early breast cancer during the past decade, according to a review of more than 700,000 cases.

The proportion of women undergoing BCT for stage T1-2 disease increased from 54.3% of cases in 1998 to 60.1% in 2011. Most of the increase occurred from 1998 to 2006 (59.7%), and the BCT rate has remained stable since then. The rise of BCT occurred to a similar extent across all age groups, in community cancer centers, and in the South, which had lagged behind other parts of the country.

Nonetheless, disparities in the application of BCT persisted in younger, less educated, uninsured, and low-income women, Isabelle Bedrosian, MD, of MD Anderson Cancer Center in Houston, and co-authors reported online in JAMA Surgery. Travel distance, geographic location, and type of cancer center (academic versus community) also affected the likelihood that a woman would undergo BCT.

“Looking at the big picture, strides have been made to reduce disparities in the use of this very effective treatment for women with early-stage breast cancer,” Bedrosian said in a statement. “But despite significant progress by the medical community, there are significant pockets of women where this therapy is underutilized. The socioeconomic barriers are unlikely to be erased without health policy changes.”

Following completion of randomized trials demonstrating the efficacy of BCT, the National Institutes of Health developed a consensus statement supporting BCT in 1990. Since then, rates of mastectomy have declined steadily and rates of BCT have increased.

Population-based studies conducted since 1990 have confirmed the increasing adoption of BCT for early breast cancer but also identified disparities in its use. One recent study suggested that practice-based disparities influenced the use of BCT, but databases used for that and other studies lacked the practice-based variables to address the question, Bedrosian and colleagues noted.

The National Cancer Data Base (NCDB) includes facility-level data (such as type of practice), in addition to clinical variables and demographics, providing a basis for revisiting the issue of practice-related disparities and their influence on use of BCT.

Investigators reviewed NCDB records for women with newly diagnosed T1-2 breast cancer during 1998 to 2011. The resulting data encompassed 727,927 patients. The principal objective was to identify factors associated with an increased or decreased likelihood of BCT.

Consistent with previous reports, the results confirmed that a majority of women with early breast cancer underwent BCT throughout the review period, but a variety of social, economic, and demographic factors influenced the likelihood that a woman would undergo BCT.

Women 52 to 70 were more likely to receive BCT than either younger or older women (P<0.01). The rate of BCT decreased significantly in women with comorbid conditions, declining to 43% of women with two or more comorbidities (P<0.01). The BCT rate was 62.3% among privately insured women versus 54% for Medicare beneficiaries, 51.5% for Medicaid enrollees, and 49.3% among uninsured women (P<0.01).

Other identified disparities included:

Median income ≥$46,000 (61.6%) versus <$30,000 (51.1%, P<0.01)
Academic centers (59.8%), comprehensive cancer centers (58.1%), community cancer programs 55.4% (P<0.01)
Living in the Northeast (64.5%) versus the South (52.0%, P<0.01)
Travel distance >17 miles (54.0%) versus less (~60%, P<0.01)

By multivariate analysis, significant associations with BCT persisted for year of diagnosis, clinical T and N stage, age, insurance status, median annual income, education level, type of treatment facility, facility location, and distance from treatment facility. The analysis did not include race/ethnicity because of “strong co-linear correlations” with socioeconomic factors, nor did it include breast cancer volume because of a strong association with facility type, the authors noted.

“Our findings suggest that travel distance may represent a surrogate for ability or willingness to access radiotherapy, a hypothesis that is supported by reports from a number of other authors,” Bedrosian and colleagues said in their discussion of the findings.

Overall, the results put a positive spin on the use of BCT and the impact of national guidelines on practice standards.

“This improvement suggests that national guidelines on breast cancer care are effectively meeting the goal of standardizing care across the U.S.,” the authors concluded.

Source: http://www.medpagetoday.com/HematologyOncology/BreastCancer/52234