Tumors that press against a muscle Cancers that cause the body to produce too many white blood cells, such as certain types of leukemia Cancer and its treatment can cause problems that cause patients to have leg cramps and other types of muscle cramps. Leg cramps or spasms are painful contractions of the muscles in the leg, ankle, or foot. However, it's important to know that other conditions and medications not related to cancer can also cause problems that could cause leg cramps. Cancer patients may experience leg cramps as a side effect of their cancer treatment or because of the nature and location of the cancer.
Change positions frequently when you sit or lie in bed for long periods of time. Muscle contractions are caused by involuntary contractions in the area or by uncontrollable contractions of a muscle group that is served by a single motor nerve fiber. A muscle contraction and a muscle spasm are involuntary contractions of a muscle, but they're not exactly the same thing. Some types of cancer can cause leg cramps, especially in the case of tumors that start in the muscle or press on a muscle.