Impact of Prior Cancer History on the Clinical Outcomes in AdvancedBreast Cancer: A Propensity Score–Adjusted, Population-Based Study / Journal of the Korean Cancer Association, 대한암학회지

ABSTRACT

Purpose@#Despite the rapid growing of cancer survivors, prior cancer history is a commonly adoptedexclusion criterion. Whether prior cancer will impact the survival of patients with advancedbreast cancer (ABC) remains uncertain. @*Materials and Methods@#Patients with ABC diagnosed between 2004 and 2010 were identified using Surveillance,Epidemiology, and End Results (SEER) database. Timing, stage, and type were used to characterizeprior cancer. Multivariable analyses using propensity score–adjusted Cox regressionand competing risk regression were conducted to evaluate the prognostic effect of priorcancer on overall survival (OS) and breast cancer-specific survival (BCSS). @*Results@#A total of 14,176 ABC patients were identified, of whom 10.5% carried a prior cancer history.The most common type of prior cancer was female genital cancer (32.4%); more than half(51.7%) were diagnosed at localized stage; most were diagnosed more than 5 years (42.9%)or less than 1 year (28.3%) prior to the index cancer. In multivariate analyses, patients withprior cancer presented a slightly worse OS (hazard ratio, 1.18; 95% confidence interval [CI],1.07 to 1.30; p=0.001) but a better BCSS (subdistribution hazard ratio, 0.64; 95% CI, 0.56to 0.74; p < 0.001). In subset analyses, no survival detriment was observed in patients withprior malignancy from head and neck or endocrine system, at in situ or localized stage, ordiagnosed more than 4 years. @*Conclusion@#Prior cancer provides an inferior OS but a superior BCSS for patients with ABC. It does notaffect the survival adversely in some subgroups and these patients should not be excludedfrom clinical trials.