Function and mobility are greatly affected in cancer survivors who have undergone treatment. The neurological system, muscles and bones are particularly vulnerable. Problems with limb weakness and loss, gait disturbance, imbalance, and other problems affecting normal walking are common in 25%–35% of cancer patients. Fatigue and visual changes may add to these mobility challenges. Mobility impairments present before the cancer may be magnified by cancer and treatment. 
Many cancer survivors have stated that their health-related quality of life is more often diminished due to physical impairments than due to psychological ones. 
Physical impairments can be assessed by an occupational therapist, a physiotherapist, or both. Often, certain cancers that are treated with surgery result in mobility or function problems. In these cases, a professional assessment and treatment might be required in the long term.
One study found that cancer survivors who participated in a community-based physical activity intervention were able to walk faster and further than those who did not participate. Their physical functioning was improved, and this was reflected in their quality of life at the end of the study. 
Evidence has shown that even though 90% of survivors need physical rehabilitation after cancer treatment, only 30% receive it, and that physical disability is the number one cause of psychological distress. 
 Silver, J. K., Baima, J., & Mayer, R. S. (2013). Impairment-driven cancer rehabilitation: An essential component of quality care and survivorship. A Cancer Journal for Clinicians, 63(5), pp. 295-317. doi: 10.3322/caac.21186