LMs may start to form during the embryonic stage, and the age at which they present in children varies, noted Dr. Smith.
Explore this issue:June 2009
Some lesions present during early childhood, whereas others present during the teen years or even during the adult years, noted Dr. Bauman.
Obtaining an MRI with contrast allows physicians to differentiate among the macrocystic, microcystic, and mixed macrocystic-microcystic lymphatic malformation subtypes, said Dr. Smith. CT scans can sometimes be misleading, as truly microcystic lesions may appear as macrocystic, he added.
Ultrasound is usually reserved for intraoperative identification of individual cysts for injection sclerotherapy; it can be used as a diagnostic tool as well, but is not as precise as MRI, he said.
Most LMs are not life-threatening, but lead to unsightly swellings of the face and neck, said Dr. Smith. Severe complications can develop when LMs expand and obstruct the upper aerodigestive tract, interfering with breathing or eating, he said.
Large LMs can compress the airway and be life-threatening, but they are fairly rare, said Dr. Kerschner. If a large lesion grows in and around the head and neck it can also affect vision, he added.
Some physicians opt for watchful waiting of these lesions if they are not causing any functional problems because a small percentage-between 1% and 5%-resolve spontaneously, said Dr. Kerschner.
Surgical excision is a treatment option for problematic macrocystic lesions, he said. However, one challenge of surgery is that LMs tend to be in close proximity to important structures such as major arteries and nerves. Given that LMs are benign lesions, resection needs to preserve as much normal function as possible, he noted.
Although a common form of therapy, surgical excision is frequently incomplete and unsatisfying, said Dr. Smith. These malformations often insinuate themselves around important nerves and blood vessels, so removal is often incomplete and associated with recurrence and morbidity. Even with meticulous dissection, disruption of the tissue lymphatics in the surgical field can lead to poor cosmetic results, he said.
Sclerotherapy is a relatively new treatment approach to macrocystic LMs that has a high success rate, said Dr. Kerschner. This treatment involves injecting a material inside the cyst cavity to irritate its contents and to make the cyst wall collapse on itself to prevent fluid from re-entering, he explained.
Agents injected into the cyst include alcohol and doxycycline, said Dr. Kerschner. However, he and his colleagues primarily use OK-432 (picibanil), an investigational drug that is a derivative of a Streptococcus organism. When injected into the cyst cavity, OK-432 creates an inflammatory response, he explained.