Surgery for Stage IV Breast Cancer: Domestic and International Disparities

Advances in systemic therapy have improved survival of womenwithmetastaticbreast cancer.TheThomaset al1 analysis of Surveillance,Epidemiology, andEndResults (SEER)data supports the concept that surgery may contribute to an outcome advantage by reducing the total body burden of disease.While this study’s overarching focus is indeedmeaningful, it is also informative to place results from this report in the context of conversations regarding breast cancer disparities associatedwith racial/ethnic identity, young age, and country of origin. First, lifetime incidence of breast cancer is lower for AfricanAmerican comparedwithwhiteAmericanwomen; therefore, African American women account for a smaller proportion of breast cancer cases compared with their general population distribution. Thomas and colleagues1 found a disproportionately high prevalence of AfricanAmericanwomen among their stage IV study population, and African Americanwomenwere also 30% less likely to undergo surgery. This treatment imbalance raisesquestions regardingselectionofpatients that are triaged toward more aggressive care. Interestingly, Park et al2 published a different analysis of SEER data, demonstrating that treatment variables are likely just as important asdisease stageand tumorbiology inexplainingbreast cancer survival improvements observed over the past several decades. Unfortunately, one can infer from these 2 SEERbased studies that inequities in the treatment offered to African American womenmay contribute to their disproportionately high breast cancer mortality risk. Second, breast cancer incidence increases with age; however, thebreastcancerburdenofyoung/premenopausalwomen generates substantial attention because of the associated impact on a population subset that assumesmuch of the nation’s family and general workforce responsibilities. Furthermore, while the population-based incidence rates of breast cancer in women younger than 45 years have been stable over the past severaldecades,weare indeedseeinga largernumberofyoung patients with breast cancer because census data confirm that this demographic has grown by nearly 10 million since 1980.3 Unfortunately, thepopulation-basedincidenceofstageIVbreast cancer has doubled among young Americanwomen4 but happily,Thomasetal1 foundthatyoungerwomenweremore likely to undergo surgery, and age younger than 45 years was an independent predictor of prolonged survival. Finally, regarding internationalpopulations,2phase3 trials comparing surgery vs no surgery in metastatic breast cancer were presented at the 2013 San Antonio Breast Cancer Symposium,with neither demonstrating a survival advantage associatedwith surgery.5 Unfortunately, both of the these studies are subject toquestions regarding their relevance in amore affluent country suchas theUnitedStates,wherepatientshave improved access to advanced diagnostic and treatment options. For example, the trial conducted in India did not includeanti-HER2/neutherapyandtheTurkish trialdidnotmandate biopsy of the metastatic focus. Both of these strategies are standard in the United States and influence survival. It is difficult (if not impossible) to identify anybreast cancer study that does not provide an opportunity to investigate disparities in disease burden and outcome.