Subgroups of cancer patients with unique pain and fatigue experiences during chemotherapy

Context. Some cancer patients experience pain and fatigue, whereas others experience only one of the two symptoms. Yet, it is not clear who experiences these unique patterns and why. Objectives. This study aimed to identify subgroups of cancer patients with unique pain and fatigue experiences in two different chemotherapy cycles to examine how selected factors influenced subgroup membership and identify how subgroups differed in concurrently measured functional limitation outcome. Methods. The sample included 276 patients with diverse cancer types from four U.S. sites. To investigate subgroups, latent profile analyses were performed. Multinomial logistic regression and one-way analysis of variance-type analyses were conducted to examine the influencing variables of subgroup membership and to examine differences among subgroups in patient outcome. Results. The high-pain/high-fatigue (HPHF) and low-pain/low-fatigue subgroups were found at both time points. The low-pain/high-fatigue subgroup was present only in the first chemotherapy cycle. Pain and fatigue levels significantly differentiated subgroups at each time point (all P \u3c 0.05). Across the two time points, experiencing higher depressed mood increased the risk to be in the HPHF subgroup (all P \u3c 0.01). The HPHF subgroup had the most serious limitations in activities (all P \u3c 0.01). Conclusion. This study confirmed the existence of a unique symptom experience of pain and fatigue. This pattern should be acknowledged for symptom assessment and management

Recommendations for high-priority research on cancer-related fatigue in children and adults.

Over the past decades, some scientific progress has been made in understanding and treating cancer-related fatigue (CRF). However, three major problems have limited further progress: lack of agreement about measurement, inadequate understanding of the underlying biology, and problems in the conduct of clinical trials for CRF. This commentary reports the recommendations of a National Cancer Institute Clinical Trials Planning Meeting and an ongoing National Cancer Institute working group to address these problems so that high-priority research and clinical trials can be conducted to advance the science of CRF and its treatment. Recommendations to address measurement issues included revising the current case definition to reflect more rigorous criteria, adopting the Patient Reported Outcomes Measurement Information System fatigue scales as standard measures of CRF, and linking legacy measures to the scales. With regard to the biology of CRF, the group identified the need for longitudinal research to examine biobehavioral mechanisms underlying CRF and testing mechanistic hypotheses within the context of intervention research. To address clinical trial issues, recommendations included using only placebo-controlled trial designs. setting eligibility to minimize sample heterogeneity or enable subgroup analysis, establishing a CRF severity threshold for participation in clinical trials, conducting dissemination trials of efficacious interventions (such as exercise), and combining nonpharmacologic and pharmacologic interventions to exploit the potential synergy between these approaches. Accomplishing these goals has the potential to advance the science of CRF and improve the clinical management of this troubling symptom

The establishment of the GENEQOL consortium to investigate the genetic disposition of patient-reported quality-of-life outcomes

To our knowledge, no comprehensive, interdisciplinary initiatives have been taken to examine the role of genetic variants on patient-reported quality-of-life outcomes. The overall objective of this paper is to describe the establishment of an international and interdisciplinary consortium, the GENEQOL Consortium, which intends to investigate the genetic disposition of patient-reported quality-of-life outcomes. We have identified five primary patient-reported quality-of-life outcomes as initial targets: negative psychological affect, positive psychological affect, self-rated physical health, pain, and fatigue. The first tangible objective of the GENEQOL Consortium is to develop a list of potential biological pathways, genes and genetic variants involved in these quality-of-life outcomes, by reviewing current genetic knowledge. The second objective is to design a research agenda to investigate and validate those genes and genetic variants of patient-reported quality-of-life outcomes, by creating large datasets. During its first meeting, the Consortium has discussed draft summary documents addressing these questions for each patient-reported quality-of-life outcome. A summary of the primary pathways and robust findings of the genetic variants involved is presented here. The research agenda outlines possible research objectives and approaches to examine these and new quality-of-life domains. Intriguing questions arising from this endeavor are discussed. Insight into the genetic versus environmental components of patient-reported quality-of-life outcomes will ultimately allow us to explore new pathways for improving patient care. If we can identify patients who are susceptible to poor quality of life, we will be able to better target specific clinical interventions to enhance their quality of life and treatment outcome

I’m so tired: biological and genetic mechanisms of cancer-related fatigue

Objective The goal of this paper is to discuss cancer-related fatigue (CRF) and address issues related to the investigation into potential biological and genetic causal mechanisms. The objectives are to: (1) describe CRF as a component of quality of life (QOL); (2) address measurement issues that have slowed progress toward an understanding of mechanisms underlying this symptom; (3) review biological pathways and genetic approaches that have promise for the exploration of causal mechanisms of CRF; and (4) offer directions for future research. Methods Review, synthesis, and interpretation of the literature. Results Until recently, CRF and QOL have been understood primarily as subjective patient-reported experiences. With increased understanding of human genetics, theories and research are being expanded to incorporate biological and genetic understandings of these subjective experiences. Proposed biological and genetic mechanisms of CRF that have been examined include cytokine dysregulation, hypothalamic-pituitary-adrenal (HPA) axis dysfunction, five hydroxy tryptophan (5-HT) neurotransmitter dysregulation, circadian rhythm disruption, alterations in adenosine triphosphate (ATP) and muscle metabolism, and vagal afferent activation. Approaches to the study of genetic mechanisms have also been addressed including candidate genes, genome-wide scanning, and gene expression. Based on the review and synthesis of the literature, directions for future research are proposed. Conclusions Understanding the biological and genetic basis of CRF has the potential to contribute to a more complete understanding of the genetic determinants of QO