The relation between muscle function and muscle pain in patients with chronic myeloid leukemia (CML): a pilot study

Chronic myeloid leukemia (CML) is a disease with a good prognosis since the
discovery of the targeted tyrosine kinase inhibitors (TKI) therapy last decade.
However, musculoskeletal pain/myalgia is a frequently reported adverse drug
reaction of TKIs (80% of patients reporting an adverse drug reaction, reports
muscle complaints), leading to poor drug adherence. To data little research has
been done on the pathogenesis and clinical management of musculoskeletal
problems during TKI therapy. This is of utmost importance since: i) the onset
of musculoskeletal problems contributes to the poor adherence to TKI therapy
and ii) continuous, potentially lifelong treatment with TKIs is required for
CML disease control. Therefore, this study will be performed to gain more
insight into the onset of TKI-induced muscle complaints, and whether they are
associated with changes in muscle function.

Primary Objective:
To investigate whether differences exist in muscle function, muscle energy
metabolism and cardiorespiratory fitness in CML patients with muscle
complaints, compared to CML patients without muscle complaints, and controls
(non-CML patients).

Secondary Objective(s):
To investigate whether differences in muscle function, energy metabolism and
cardiorespiratory fitness relate to pain intensity, fatigue and quality of
life.

A cross-sectional, observational study with invasive measurements will allow
comparison of muscle function, muscle energy metabolism and cardiorespiratory
fitness between CML patients with muscle complaints, CML patients without
muscle complaints and controls (non-CML patients).

During this study CML patients will not be exposed to a major risk, as standard
care will not be withheld: patients will not be taken off their medication and
will be carefully screened by a medical doctor.
Contra-indications for the maximal aerobic cycling test and muscle biopsy will
be checked during the medical screening procedure and are listed as exclusion
criteria for the study.
Venous blood withdrawal and collection of a muscle biopsy can induce a local
hematoma (<5%). However, this is completely reversible within 2 weeks and will
not induce permanent damage. Collection of a muscle biopsy will leave a small
scar.
Taken together, the nature and extent of burden and risks associated with the
different measurements are negligible.