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
303P - Segmental mandibulectomy without reconstruction
Presenter: Yohei Morishita
Session: Poster display session
Resources:
Abstract
304P - Survival outcomes and survival predictors in recurrent and metastatic head and neck squamous cell cancer (R/M-HNSCC) patients treated with chemotherapy (CT) plus cetuximab as first-line therapy in a real-world study
Presenter: Filipa Pontes
Session: Poster display session
Resources:
Abstract
305P - A retrospective study to evaluate patient characteristics for recurrent head and neck cancer after definitive treatment
Presenter: Tetsuro Wakasugi
Session: Poster display session
Resources:
Abstract
306P - Efficacy and safety of apatinib in heavily pretreated metastatic adenocarcinoma of the head and neck
Presenter: Lin Gui
Session: Poster display session
Resources:
Abstract
307P - Lacrimal gland tumours: Clinical and epidemiological patterns in the United States
Presenter: Mahmoud KhalafAllah
Session: Poster display session
Resources:
Abstract
308P - Dental prophylaxis and 5-fluorouracil related oral mucositis in head and neck cancer patients: A population-based cohort study
Presenter: Yi-Fang Huang
Session: Poster display session
Resources:
Abstract
309P - Evaluation of a pharmacist-led opioid de-escalation (PLODE) program after chemoradiotherapy completion in head and neck cancer patients
Presenter: Ai Horinouchi
Session: Poster display session
Resources:
Abstract
310P - Laser and PDT for the oral leukoplakia
Presenter: Sadykov Rasul
Session: Poster display session
Resources:
Abstract
311P - Incidence of thyroid carcinoma in the Philippines: A retrospective study from a tertiary university hospital
Presenter: Priscilla Caguioa
Session: Poster display session
Resources:
Abstract
312P - Oral health disparities among privileged and underprivileged tribes of south India - A study on precancerous oral lesions prevalence
Presenter: Shanavas Palliyal
Session: Poster display session
Resources:
Abstract