Physical frailty as a sign of accelerated aging is not well characterized in breast cancer (BC) and hematopoietic cell transplant (HCT) survivors and its correlation with outcomes and quality of life (QOL) is not defined. We conducted a prospective study to determine the prevalence of frailty in adult BC and HCT survivors, examine its impact on QOL, and determine its association with p16INK4a, a molecular biomarker for biological aging. The study included 59 BC and 65 HCT survivors. Median age was 60 years (range 27-81), 68.5% were female and 49.2% were 18-59 vs. 51.8% ≥60 years old. A total of 71 (57.3%) were "fit" (frailty score 0) vs. 53 (42.7%) were pre-frailty/frail (frailty scores ≥1), and of the latter 17 (32.1%) were BC and 36 (67.9%) HCT patients. On multivariate analysis, patients >60 years were twice as likely to be frail (OR 2.04, 95% CI, 0.96-4.33; p=0.07), HCT were more likely to be frail compared to BC patients, and female HCT had 2.43 (95% CI, 0.92-6.40) and male HCT patients had 3.25 (95% CI, 1.37-7.72) times higher risk of frail; p=0.02. Frailty was associated with significant decline in QOL, measured by Medical Outcomes Study (MOS) Short Form 36 (SF-36) Physical Component Summary (PCS) and Mental Component Summary (MCS), and FACT (Functional Assessment of Cancer Therapy) scores. p16INK4a expression was higher in those who were frail, older than 60, and with higher expression in frail vs. fit patients who are 18-59 years. Our study highlights the high prevalence of frailty in survivors with detrimental effects on physical and overall wellbeing, and supports an association between frailty and the senescence marker p16INK4a.
Keywords: aging; breast cancer; cellular senescence; frailty; hematopoietic cell transplantation.