Lymphatic and Mixed Malformations.

Lymphatic and mixed malformations are rare and variable in presentation. They arise due to errors in vascular and lymphatic formation during early embryonic development. This leads to persistent infiltration of lymph fluid into soft tissues and causes a locally invasive mass with pathologic sequelae. Departing from historically descriptive terminology, such as "cystic hygroma," lymphatic malformations are now categorized as macrocystic, microcystic, or mixed lesions, based on size. Advances in imaging modalities, such as ultrasonography and magnetic resonance imaging, have made accurate characterization of these lesions possible and ultimately allow for early diagnosis and implementation of appropriate treatment based on the morphology of the lymphatic malformation. Management of lymphatic malformations can be quite challenging, and a multidisciplinary approach is most effective for optimum aesthetic and functional outcomes. New discoveries in the molecular biology of lymphatic malformations have provided treatment targets and established a role for pharmacotherapy. Sclerotherapy, laser, and radiofrequency ablation have all proven to be effective as minimally invasive treatment options for lymphatic malformations. Surgical intervention has a role in the treatment of focal lesions recalcitrant to these less invasive techniques. Operative planning is dictated by clinical goals, size, anatomic location, characteristics, and extent of infiltration.