Rehabilitation is an integral part of cancer care and aims to maximise the functional ability and independence of patients, whatever the stage of their disease.1 To help achieve this, there is a need to identify which (if any) symptoms limit the patient’s ability to undertake activities of daily living. Patients with cancer commonly report breathlessness on exertion, and practitioners may assume that the breathlessness is the limiting symptom and may not enquire about peripheral muscle fatigue, even though this is known to contribute to exercise limitation in patients with cardiopulmonary disease and healthy volunteers.2 We have begun to explore whether breathlessness and peripheral muscle fatigue limit activities of daily living in patients with cancer who report breathlessness on exertion. Ethical approval was received from Nottingham City Hospital ethics committee.

Sixty-two patients (37 men) admitted to a specialist palliative care unit for symptom control or respite were included in the study. Their median age was 70 years (range 28–92) and median survival was 8 weeks (range 1–120). They had a variety of cancers (22 genitourinary, 8 gastrointestinal, 5 breast, 2 lymphoma, 4 other) with one-third having either primary (14 non-small cell lung cancer, 3 mesothelioma, 1 small cell lung cancer) or secondary (2 colorectal, 1 renal) thoracic cancer. None had received surgery, chemotherapy or radiotherapy within the last month or were limited by pain. Participants were asked to identify which one of the six statements (scored between 0 and 5) in the Dyspnoea Exertion Scale (DES) best described their experience of breathlessness. The DES is a modified version of the Medical Research Council Dyspnoea Scale which better discriminates patients breathless at lower levels of activity.3 4 They also indicated the limiting symptom for various activities of daily living which they undertook independently: breathlessness alone, limb muscle fatigue alone, or breathlessness and limb muscle fatigue equally.

All patients scored between 2 and 4 on the DES scale. The results suggest that, in patients with cancer experiencing breathlessness at various levels of exertion, muscle fatigue is also an important limiting symptom (table 1).

Our findings are consistent with those in other patient groups such as patients with chronic obstructive pulmonary disease or those with cardiac failure undertaking lower limb exercise, and with the importance given to limb muscle exercise in rehabilitation programmes.2 5 It may be most appropriate to examine whether a similar rehabilitative approach offered to patients with cancer soon after diagnosis could help those undergoing potentially curative treatment to recover more quickly, or for those with incurable disease to remain as independent as possible for as long as possible. A more detailed and prospective evaluation of which symptoms limit activity is warranted, and we are currently undertaking this in patients with lung cancer carrying out a walking exercise test.