Randomized Pilot Study for the Treatment of Cutaneous Leiomyomas With Botulinum Toxin

Cutaneous leiomyomas are benign tumors of smooth muscle origin. They can be very painful, and current treatments for the tumors and for the associated pain do not produce satisfactory results. One potential treatment for localized severe muscle pain involves injections with botulinum toxin A. This study will investigate the effectiveness, side effects, and dosage of botulinum toxin A (BOTOX) as a treatment for patients with pain associated with cutaneous leiomyomas. This study will include 18 subjects, all of whom will be 18 years of age and older, who have pain associated with cutaneous leiomyomas. For the 24-week study, patients will be randomly assigned to one of two treatment groups. Neither the study team nor the patient will know to which group patients have been assigned. Before the study begins, all participants must provide a full medical history for research and evaluation purposes, fill out pain and quality-of-life questionnaires, and undergo an ice test in which researchers will apply ice to the site of the cutaneous leiomyomas and ask participants to evaluate the level of pain before and after ice application. Both groups will be required to keep a pain diary throughout the study to record their level of pain on a daily basis, and will be asked to avoid or restrict the use of specific medications or other remedies to treat the pain. At the first visit (Week 0), one group will receive a prescribed dose of botulinum toxin A, which will be administered as an injection into the leiomyoma, and the other (control) group will receive a placebo injection of a saline solution. Patients will return 4 weeks later, at which time they will undergo a medical examination, and the ice test, and complete questionnaires to assess responses and level of pain. Patients will return in Week 12, at which time the group assignment will be revealed (un-blinded) to investigators and patients. Patients who received placebo injections will be offered the opportunity to receive injection of botulinum toxin A into their leiomyomas. All patients will undergo a medical examination, the ice test, complete questionnaires, and continue completing their daily pain diaries at home. The final visit, in Week 24, will follow the same procedure as the Week 4 visit. At the end of the study, patients may be eligible to have one or more of the painful cutaneous leiomyomas surgically removed if the researchers believe that the skin lesions can be removed with a reasonable cosmetic result.