Imputing estrogen receptor (ER) status in a population-based cancer registry: a sensitivity analysis

Missing Components of Receptor Status Among Women With Invasive Breast Cancer

Importance

There are well-known differences in patient outcomes and effective therapeutic options across subtypes of breast cancer (BC), defined by the status of estrogen receptor, progesterone receptor, and erb-B2 receptor tyrosine kinase 2 (ERBB2 [formerly HER2]) expression, making testing for these receptors part of the routine workup for all patients with a diagnosis of invasive BC. Despite its importance, this information is missing in some BC cases.

Objective

To identify female patients with BC without record of testing for estrogen receptor, progesterone receptor, or ERBB2 status, defined as missing components of receptor status (MCRS).

Design, Setting, and Participants

This cross-sectional study used data from National Cancer Institute's Surveillance, Epidemiology and End Results Program of 18 population-based registries from women with a diagnosis of invasive BC (excluding death certificate-only and autopsy cases) from January 2012 to December 2016. The final analyses were completed in February 2022.

Main Outcome and Measure

The primary outcome was MCRS. Those with MCRS were summarized by age, race, stage at diagnosis, reporting source, primary payer, and geography. Multivariable logistic regression was used to estimate adjusted odds ratios (aORs) for MCRS.

Results

Overall, 321 913 patients with invasive BC were included (1928 [1%] American Indian or Alaska Native, 28 173 [9%] Asian or Pacific Islander, 36 357 [11%] Black, and 252 447 [78%] White individuals); of these, 15 250 (4.7%) had MCRS. The multivariable model showed that the odds of MCRS were higher in women 80 years or older compared with those younger than 49 years (aOR, 1.75; 95% CI, 1.65-1.88), Black compared with White women (aOR, 1.09; 95% CI, 1.00-1.16), and those with distant stage or unknown/unstaged cancer at diagnosis compared with a local stage at diagnosis (aOR, 3.33; 95% CI, 3.17-3.50; and aOR, 19.39; 95% CI, 18.15-20.72; respectively). With hospital inpatient/outpatient or clinic as the reference group, cases reported by laboratory only, nursing/convalescent home/hospice, and a physician's office were more likely to have MCRS (aOR, 1.42; 95% CI; 1.28-1.60; aOR, 9.37; 95% CI, 6.03-14.53; and aOR, 2.32; 95% CI, 2.06-2.62; respectively). Adjusted odds of MCRS were higher for the categories of insured/no specifics and insurance status unknown compared with those who were insured. The adjusted odds of MCRS were higher in rural compared with urban areas (aOR, 1.08; 95% CI, 1.03-1.15).

Conclusions and Relevance

The results of this cross-sectional study of women with a diagnosis of invasive BC suggest that despite a standard of care recommended by all expert guidelines, there needs to be greater focus on hormone receptor and ERBB2 testing in all women with invasive BC. The results of this study may help clinicians, public health practitioners, and policymakers target affected populations to minimize or eliminate this critical health disparity and help save more lives.

Neoadjuvant Chemotherapy, Endocrine Therapy, and Targeted Therapy for Breast Cancer: ASCO Guideline

PURPOSE

To develop guideline recommendations concerning optimal neoadjuvant therapy for breast cancer.

METHODS

ASCO convened an Expert Panel to conduct a systematic review of the literature on neoadjuvant therapy for breast cancer and provide recommended care options.

RESULTS

A total of 41 articles met eligibility criteria and form the evidentiary basis for the guideline recommendations.

RECOMMENDATIONS

Patients undergoing neoadjuvant therapy should be managed by a multidisciplinary care team. Appropriate candidates for neoadjuvant therapy include patients with inflammatory breast cancer and those in whom residual disease may prompt a change in therapy. Neoadjuvant therapy can also be used to reduce the extent of local therapy or reduce delays in initiating therapy. Although tumor histology, grade, stage, and estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2) expression should routinely be used to guide clinical decisions, there is insufficient evidence to support the use of other markers or genomic profiles. Patients with triple-negative breast cancer (TNBC) who have clinically node-positive and/or at least T1c disease should be offered an anthracycline- and taxane-containing regimen; those with cT1a or cT1bN0 TNBC should not routinely be offered neoadjuvant therapy. Carboplatin may be offered to patients with TNBC to increase pathologic complete response. There is currently insufficient evidence to support adding immune checkpoint inhibitors to standard chemotherapy. In patients with hormone receptor (HR)-positive (HR-positive), HER2-negative tumors, neoadjuvant chemotherapy can be used when a treatment decision can be made without surgical information. Among postmenopausal patients with HR-positive, HER2-negative disease, hormone therapy can be used to downstage disease. Patients with node-positive or high-risk node-negative, HER2-positive disease should be offered neoadjuvant therapy in combination with anti-HER2-positive therapy. Patients with T1aN0 and T1bN0, HER2-positive disease should not be routinely offered neoadjuvant therapy.Additional information is available at www.asco.org/breast-cancer-guidelines.

Differences in Breast Cancer Survival by Molecular Subtypes in the United States

Background: Although incidence rates of breast cancer molecular subtypes are well documented, effects of molecular subtypes on breast cancer-specific survival using the largest population coverage to date are unknown in the U.S.

POPULATION

Methods: Using Surveillance, Epidemiology and End Results cancer registry data, we assessed survival after breast cancer diagnosis among women diagnosed during 2010 to 2013 and followed through December 31, 2014. Breast cancer molecular subtypes defined by joint hormone receptor [HR, estrogen receptor (ER) and/or progesterone receptor (PR)] and HER2 status were assessed. Multiple imputation was used to fill in missing receptor status. Four-year breast cancer-specific survival per molecular subtypes and clinical/demographic factors were calculated. A Cox proportional hazards model was used to evaluate survival while controlling for clinical and demographic factors.Results: The best survival pattern was observed among women with HR⁺/HER2^- subtype (survival rate of 92.5% at 4 years), followed by HR⁺/HER2⁺ (90.3%), HR^-/HER2⁺ (82.7%), and finally worst survival for triple-negative subtype (77.0%). Notably, failing to impute cases with missing receptor status leads to overestimation of survival because those with missing receptor status tend to have worse prognostic features. Survival differed substantially by stage at diagnosis. Among de novo stage IV disease, women with HR⁺/HER2⁺ subtype experienced better survival than those with HR⁺/HER2^- subtype (45.5% vs. 35.9%), even after controlling for other factors.Conclusions: Divergence of survival curves in stage IV HR⁺/HER2⁺ versus HR⁺/HER2^- subtype is likely attributable to major advances in HER2-targeted treatment.Impact: Contrary to conventional thought, HR⁺/HER2⁺ subtype experienced better survival than HR⁺/HER2^- in advanced-stage disease. Cancer Epidemiol Biomarkers Prev; 27(6); 619-26. ©2018 AACR.

Breast Cancer Estrogen Receptor Status According to Biological Generation: US Black and White Women Born 1915-1979

Evidence suggests that contemporary population distributions of estrogen-receptor (ER) status among breast cancer patients may be shaped by earlier major societal events, such as the 1965 abolition of legal racial discrimination in the United States (state and local "Jim Crow" laws) and the Great Famine in China (1959-1961). We analyzed changes in ER status in relation to Jim Crow birthplace among the 46,417 black and 339,830 white US-born, non-Hispanic women in the Surveillance, Epidemiology, and End Results (SEER) 13 Registry Group who were born between 1915 and 1979 and diagnosed (ages 25-84 years, inclusive) during 1992-2012. We grouped the cases according to birth cohort and quantified the rate of change using the haldane (which scales change in relation to biological generation). The percentage of ER-positive cases rose according to birth cohort (1915-1919 to 1975-1979) only among women diagnosed before age 55. Changes according to biological generation were greater among black women than among white women, and among black women, they were greatest among those born in Jim Crow (versus non-Jim Crow) states, with this group being the only group to exhibit high haldane values (>|0.3|, indicating high rate of change). Our study's analytical approach and findings underscore the need to consider history and societal context when analyzing ER status among breast cancer patients and racial/ethnic inequities in its distribution.