Mitochondrial DNA content in peripheral blood as a biomarker for cancer-related fatigue in early-stage breast cancer patients: A prospective cohort study.

10018Background: Cancer-related fatigue (CRF) is reported to be associated with mitochondrial dysfunction. Hence, mitochondrial DNA (mtDNA) content, a biomarker of mitochondrial dysfunction, is hypothesized to correlate with the onset of CRF. This study aimed to evaluate the association between peripheral blood mtDNA content and CRF in patients receiving chemotherapy. Methods: This was a prospective cohort study. Early-stage breast cancer patients (Stages I to III) receiving anthracycline or taxane-based chemotherapy were recruited. CRF was assessed using the validated Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) at two time points: baseline (T1; prior to treatment) and 6 weeks after initiation of treatment (T2). Worsening of CRF was defined as ≥10% increase in the overall MFSI-SF score at T2. Peripheral blood mtDNA content was measured at both time points using real-time quantitative polymerase chain reaction. Multiple logistic regression was utilized to evaluate the association betwee...