Introduction: Lymphatic malformations (LM) are benign structural defects that can cause serious complications because of their size and location. Traditionally, surgical removal was the first treatment modality, but this could be associated with many complications and risks. Since Ogita introduced OK-432 (picibanil) in 1987 as a treatment method, this sclerosant has become popular. This paper is a review of the trials published so far on this topic.
Patients and methods: A literature search of English trials with 5 or more patients in it with LM who had never been treated before was done. The paper had to use the microcystic-macrocystic classification and have a mean follow-up of more than a year to be included in this review. Results were classified as "excellent" when the lesions show a regression of more than 90%, "good" when regression is more than 50%, and "poor" when shrinkage is less than 50% (this also includes no response at all).
Results: Twenty-seven percent of microcystic LMs show an excellent result; 33%, a good result; and 40%, a poor result. Of the macrocystic LMs, 88% have excellent results. Recurrence rates vary from 5% to 8%. The adverse effects are mostly mild.
Discussion: Most trials have a short follow-up; therefore, there are uncertainties when it comes to cure and regression. Mostly, the adverse effects of OK-432 are trivial and disappear after a week, but the need for a temporary tracheostomy has been described. Screening for allergic reactions to penicilline is needed, with the risk of anaphylactic shock in mind. It is difficult to compare the different techniques used by the authors, and none of the trials included in this study are randomized controlled trials; most are retrospective and were so-called level 4 studies.
Conclusions: This review demonstrates that OK-432 is an effective way to treat LM. Because of a possible risk of airway obstruction, treatment should always take place in specialized treatment facilities. Macrocystic lesions show a better response to OK-432 treatment than microcystic lesions. Serious complications with OK-432 are infrequent, and this type of sclerotherapy seems to have no influence on future surgery. We therefore suggest the use of OK-432 as an effective first-line treatment of LMs.