Treatment
In asymptomatic patients without functional impairment or significant cosmetic concerns, careful observation is warranted. If treatment is indicated, options include surgery, sclerotherapy, or medical treatment with sirolimus; either alone or in combination. Surgical treatment for LM is most successful in patients with localized malformations that do not invade important adjacent structures (37), but debulking procedures for large, complex malformations may be indicated. Surgery could be offered to the patient above, but sclerotherapy is the most reasonable approach given high success rates with treatment of macrocytic lesions. Sclerotherapy is the first line treatment for macrocystic or mixed micro/macrocystic lesions (64), but is less efficacious for microcystic LMs (65). In microcystic lesions medical therapy with sirolimus has been shown to be beneficial in softening the lesions and also decreasing the size in general, leading to an improved quality of life (66).
Unless symptomatic, sclerotherapy is often not performed until the patient is at least 6 months of age. Given the location and symptomatic nature of the patient above, sclerotherapy would be the preferred treatment course for this patient. For treatment of LMs, a needle is inserted into the cystic space, lymphatic fluid is drained, and sclerosing agent is injected. Large cysts may require multiple injections over 24 to 48 hours, so a pigtail catheter is inserted to facilitate repeated injections (37,64). Similar to VMs, success of sclerotherapy is dependent on the sclerosing agent used, dwell time, and type of LM. Higher rates of cure are seen in macrocystic LMs, as the entire endothelium can be treated. Doxycycline has the highest success rates for LM, with a meta-analysis of treated head and neck LM demonstrating an 80% efficacy rate (34). For lesions in the head and neck area, which involve the airway, orbit or are close to nerves, bleomycin, which causes minimal swelling, is the agent of choice (65). Dose dependent pulmonary toxicity is a potential complication of bleomycin therapy. Bleomycin doses in sclerotherapy are typically much smaller than the cumulative dose of 400 mg or greater that is associated with toxicity (68). Macrocystic LMs respond well to treatment with OK-432, but microcystic or mixed lesions have a less favorable response (37). LMs can re-expand over time and require repeated procedures.