Mitigating long-term and delayed adverse events associated with cancer treatment: implications for survivorship

Despite the importance of chemotherapy-associated adverse events in oncology practice and the broad range of interventions available to mitigate them, limited systematic efforts have been made to identify, critically appraise and summarize the totality of evidence on the effectiveness of these interventions. Herein, we review the most common long-term (continued beyond treatment) and late or delayed (following treatment) adverse events associated with chemotherapy and other anticancer treatments that pose major threats in terms of survival, quality of life and continuation of optimal therapy. These adverse effects often emerge during and continue beyond the course of therapy or arise among survivors in the months and years following treatment. For each of these adverse effects, we discuss and critically evaluate their underlying biological mechanisms, the most commonly used pharmacological and non-pharmacological treatment strategies, and evidence-based clinical practice guidelines for their appropriate management. Furthermore, we discuss risk factors and validated risk-assessment tools for identifying patients most likely to be harmed by chemotherapy and potentially benefit from effective interventions. Finally, we highlight promising emerging supportive-care opportunities for the ever-increasing number of cancer survivors at continuing risk of adverse treatment effects.

Corticosteroids for the management of cancer-related fatigue in adults with advanced cancer

BACKGROUND

Fatigue is the most commonly reported symptom in people with advanced cancer. Cancer-related fatigue (CRF) is pervasive and debilitating, and can greatly impact quality of life (QoL). CRF has a highly variable clinical presentation, likely due to a complex interaction of multiple factors. Corticosteroids are commonly used to improve CRF, but the benefits are unclear and there are significant adverse effects associated with long-term use. With the increasing survival of people with metastatic cancer, the long-term effects of medications are becoming increasingly relevant. Since the impact of CRF can be immensely debilitating and can negatively affect QoL, its treatment warrants further review.

OBJECTIVES

To determine the benefits and harms of corticosteroids compared with placebo or an active comparator in adults with advanced cancer and CRF.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, Science Citation Index (ISI Web of Science), LILACS, and two clinical trial registries from inception to 18 July 2022.  SELECTION CRITERIA: We included randomised controlled trials in adults aged ≥18 years. We included participants with advanced cancer who were suffering from CRF. We included trials that randomised participants to corticosteroids at any dose, by any route, administered for the relief of CRF; compared to placebo or an active comparator, including supportive care or non-pharmacological treatments.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed titles identified by the search strategy; two review authors assessed risk of bias; and two extracted data. We extracted the primary outcome of participant-reported fatigue relief using validated scales and secondary outcomes of adverse events, serious adverse events and QoL. We calculated the risk ratio with 95% confidence intervals (CIs) between groups for dichotomous outcomes. We measured arithmetic mean and standard deviation, and reported the mean difference (MD) with 95% CI between groups for continuous outcomes. We used standardised mean difference (SMD) with 95% CIs when an outcome was measured with different instruments measuring the same construct. We used a random-effects model to meta-analyse the outcome data. We rated the certainty of the evidence using GRADE and created two summary of findings tables.  MAIN RESULTS: We included four studies with 297 enroled participants; data were available for only 239 participants. Three studies compared corticosteroid (equivalent ≤ 8 mg dexamethasone) to placebo. One study compared corticosteroid (dexamethasone 4 mg) to an active comparator (modafinil 100 mg). There were insufficient data to evaluate subgroups, such as dose and duration of treatment. One study had a high risk of performance and detection bias due to lack of blinding, and one study had a high risk of attrition bias. Otherwise, we assessed risks of bias as low or unclear. Comparison 1: corticosteroids compared with placebo Participant-reported fatigue relief The was no clear difference between corticosteroids and placebo (SMD -0.46, 95% CI -1.07 to 0.14; 3 RCTs, 165 participants, very low-certainty evidence) for relief of fatigue at one week of the intervention. We downgraded the certainty of the evidence three times for study limitations due to unclear risk of bias, imprecision, and inconsistency. Adverse events There was no clear difference in the occurrence of adverse events between groups, but the evidence is very uncertain (3 RCTs, 165 participants; very low-certainty evidence). Serious adverse events There was no clear difference in the occurrence of serious adverse events between groups, but the evidence is very uncertain (2 RCTs, 118 participants; very low-certainty evidence). Quality of lIfe One study reported QoL at one week using the Edmonton Symptom Assessment System (ESAS) well-being, and found no clear difference in QoL between groups (MD -0.58, 95% CI -1.93 to 0.77). Another study measured QoL using the Quality of Life Questionnaire for Cancer Patients Treated with Anticancer Drugs (QoL-ACD), and found no clear difference between groups. There was no clear difference between groups for either study, but the evidence is very uncertain (2 RCTs, 118 participants; very low-certainty evidence).  Comparison 2: corticosteroids compared with active comparator (modafinil) Participant-reported fatigue relief There was improvement in fatigue from baseline to two weeks in both groups (modafinil MD 10.15, 95% CI 7.43 to 12.87; dexamethasone MD 9.21, 95% CI 6.73 to 11.69), however no clear difference between the two groups (MD -0.94, 95% CI -4.49 to 2.61; 1 RCT, 73 participants, very low-certainty evidence). We downgraded the certainty of the evidence three times for very serious study limitations and imprecision. Adverse events There was no clear difference in the occurrence of adverse events between groups, but the evidence is very uncertain (1 RCT, 73 participants; very low-certainty evidence).  Serious adverse events There were no serious adverse events reported in either group (1 RCT, 73 participants; very low-certainty evidence).  Quality of lIfe One study measured QoL at two weeks, using the ESAS-well-being. There was marked improvement in QoL from baseline in both groups (modafinil MD -2.43, 95% CI -2.88 to -1.98; dexamethasone MD -2.16, 95% CI -2.68 to -1.64), however no clear difference between the two groups (MD 0.27, 95% CI -0.39 to 0.93; 1 RCT, 73 participants, very low-certainty evidence).

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the use of systemic corticosteroids in adults with cancer and CRF. We included four small studies that provided very low-certainty of evidence for the efficacy of corticosteroids in the management of CRF. Further high-quality randomised controlled trials with larger sample sizes are required to determine the effectiveness of corticosteroids in this setting.

Exercise oncology: an emerging discipline in the cancer care continuum

Exercise is an essential component of healthy living and well-being. While there is a global acceptance of the benefits of exercise for the general population, there exists hesitancy and confusion among health-care professionals, particularly oncologists, as to whether these benefits translate to cancer patients. Patient referrals to accessible, structured exercise programs in this setting are often overlooked by physicians when formulating a cancer management plan. There is however increasing awareness and acceptance of cancer survivorship as a part of the cancer care continuum, identifying multiple factors that contribute to well-being beyond just cancer outcomes. Efforts to optimize cancer survivorship have stimulated further academic interest in the benefits of healthy living and particularly exercise oncology. There is now compelling evidence that exercise, which includes daily activities such as walking, as well as structured programs, improves multiple-cancer outcomes such as fatigue, quality of life and likely survival, and warrants consideration in the multidisciplinary care of cancer patients. International guidelines have been established that recommend counseling cancer patients with regard to healthy lifestyle changes including exercise. However, there still remains a reluctance from oncology physicians to prescribe exercise for these patients, largely due to uncertainty with regard to their patients' ability to tolerate such an intervention, coupled with insufficient understanding of the potential benefits of these programs. There also exist patient barriers and attitudes that must be overcome. Exercise strategies and bespoke programs that are tailored to the unique abilities and goals of the patients will enhance participation. To move the field forward and integrate exercise oncology into standard practice, it is imperative to raise awareness of the benefits of exercise to cancer patients and their health-care providers. This will facilitate the prescription of exercise as part of the multimodal treatment plan with the ultimate aim of promoting an active lifestyle to optimize patient care and well-being.