For patients with advanced cancer-associated dyspnoea, a hierarchical approach beginning with an assessment and non-pharmacologic interventions before moving on to pharmacologic options is recommended, according to a new guideline from the American Society of Clinical Oncology (ASCO).
“[Dyspnoea] is one of the most common and distressing symptoms affecting patients with advanced cancer,” wrote guideline authors led by Dr David Hui, of MD Anderson Cancer Center in Houston. A longitudinal observational study of patients with lung cancer found it to be consistently ranked as the most distressing symptom, and its presence often indicates a poor prognosis of less than a few months.
The new guideline examined 48 randomised controlled trials and two retrospective cohort studies, with lung cancer and mesothelioma as the most commonly addressed types of cancer.
The guideline recommends a systematic assessment of dyspnoea at every inpatient and outpatient encounter in patients with advanced cancer, and patients experiencing the symptom should undergo a comprehensive evaluation for the severity, triggers, underlying causes, and associated symptoms, along with its emotional and functional impact.
Some patients will have potentially reversible dyspnoea associated with underlying etiologies such as pleural effusion, airway obstruction, anaemia, and others, and treatment for those causes can be offered if in accordance with a patient’s wishes and depending on their overall health status.
Support for pharmacologic interventions was “limited,” and as such clinicians should generally begin with non-pharmacologic interventions. These can include airflow interventions such as directing a fan at the cheek and supplemental oxygen, as well as breathing techniques, posture, relaxation, distraction, meditation, and physical therapy. Time-limited therapeutic trials of high-flow nasal cannula oxygen therapy may be offered to those with significant dyspnoea and hypoxaemia despite standard supplemental oxygen.
The authors, which included Prof. David Currow, Professor of palliative medicine at at ImPACCT, UTS, noted that evidence remains insufficient regarding the use of pulmonary rehabilitation in patients with advanced cancer and dyspnoea.
When non-pharmacologic interventions fail to provide relief, clinicians can offer systemic opioid therapy. Short-acting benzodiazepines are indicated for patients who experience dyspnoea-related anxiety and who continue to have symptoms despite opioids and other interventions.
Systemic corticosteroids are more rarely indicated, only in patients with airway obstruction or when inflammation is a likely key contributor. Bronchodilators should be used for palliation when patients have established obstructive pulmonary disorders or evidence of bronchospasm.
The authors noted that relatively few RCTs have been conducted on treatments for dyspnoea in advanced cancer. “These studies are particularly difficult to complete because the patients with advanced cancer and dyspnea are often in distress and have a poor performance status and short survival,” they wrote.
The evidence still remains insufficient regarding other pharmacologic interventions, including the use of antidepressants, neuroleptics, or inhaled furosemide. When other interventions have failed and patients have an expected life of days, continuous palliative sedation should be offered.
“Given the high prevalence of this symptom in patients with advanced cancer, its distressing nature, and functional impact, more high-quality research is needed to develop novel interventions to support patients and informal caregivers,” they concluded.