Abstract 438P
Background
Given that CRF is characterized by a lack of energy, it is postulated that mitochondrial dysfunction may contribute to its etiology. Using mitochondrial DNA (mtDNA) copy number and displacement-loop (D-loop) mutation status, this study aims to evaluate mtDNA content between fatigue subclasses, over the course of chemotherapy.
Methods
In a prospective cohort study, early-stage breast patients’ fatigue levels were assessed using the validated Multi-Dimensional Fatigue Symptom Inventory–Short Form (MFSI-SF) and their blood was drawn before, during and after treatment. Relative mtDNA copy number was determined via real-time quantitative polymerase chain reaction while mitochondrial genome was sequenced directly for D-loop mutations at nucleotide positions 303, 489 and 514. Subclasses of extent of fatigue was derived using latent class analysis, based on magnitude of change in sub-domain scores after treatment, with respect to baseline. Clinically relevant factors that differentiate the identified subclasses were then compared between the fatigued groups.
Results
A total of 133 patients (mean age ± SD: 51.2 ± 8.8 years, median mtDNA: 71.0) were classified into two fatigue subclasses: mild fatigue (75.2%) and fatigued group (24.8%) respectively. Based on mtDNA trajectory, patients who are predisposed to CRF started off with lower baseline values and experienced slower recovery. Median mtDNA content was reduced over 12 weeks after initiation of chemotherapy (p < 0.001) and was reported to be consistently lower in fatigued group (T2: 48.0 vs 56.0; T3: 61.4 vs 66.0) although the difference was not found to be statistically significant. The proportion of patients with D-loop mutation status was comparable between fatigued group and mild fatigue (303: 81.8% vs 73.0%, 489: 45.5% vs 47.0% and 514: 45.5% vs 53.0%). However, no association was reported between mtDNA levels over time or D-loop mutation with CRF status.
Conclusions
mtDNA content and D-loop mutation status do not sufficiently differentiate fatigue subclasses, suggesting that future research may be needed to study the differential expression of mitochondrial dysfunction-related genes and the pathways they may perturb.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
National University of Singapore.
Funding
National Medical Research Council.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
51P - Enhancing the anti-breast tumour activity of STING through a novel sting transcriptional regulator
Presenter: Hanchu Xiong
Session: Poster display session
Resources:
Abstract
52P - Reverse Warburg effect-related mitochondrial activity and 18F-FDG uptake in invasive ductal carcinoma
Presenter: Byung Wook Choi
Session: Poster display session
Resources:
Abstract
53P - Phase II study of atorvastatin in combination with radiotherapy and temozolomide in patients with glioblastoma (ART): Final analysis report
Presenter: Abdullah Altwairgi
Session: Poster display session
Resources:
Abstract
54P - Association between Parkinson’s disease and brain tumours: A nationwide population-based cohort study
Presenter: Joo-hyun Park
Session: Poster display session
Resources:
Abstract
55P - Toxicity profiles of treatment with modern fractionated radiotherapy, contemporary stereotactic radiosurgery, or transsphenoidal surgery in non-functioning pituitary macroadenoma
Presenter: Kevin Sheng-Po Yuan
Session: Poster display session
Resources:
Abstract
56P - Hippocampal avoidance in WBRT for metastases: Comparative neurocognitive and dosimetric assessment
Presenter: Vibhay Pareek
Session: Poster display session
Resources:
Abstract
57P - Multidisciplinary brain metastasis clinic: Is it effective and worthwhile?
Presenter: Annu Rajpurohit
Session: Poster display session
Resources:
Abstract
58P - Functional status as a determinant prognostic factor for overall survival in adult patients with medulloblastoma treated with chemotherapy and radiotherapy
Presenter: Juan Ayala Alvarez
Session: Poster display session
Resources:
Abstract
59P - Pattern of care in high-grade gliomas after recurrence
Presenter: Nandini Menon
Session: Poster display session
Resources:
Abstract
60P - Five fractions plus “SRS” boost combined with temozolamide for newly diagnosed and recurrent glioblastoma multiforme (GBM)
Presenter: Azhar Rashid
Session: Poster display session
Resources:
Abstract