Patients with lymphatic malformations who receive the immunostimulant OK-432 experience excellent long-term outcomes.

Aim: Sclerotherapy is the primary treatment for lymphatic malformations. The aim of this study was to evaluate the long-term outcome in patients with lymphatic malformations treated with the immunostimulant OK-432 as a sclerosant.

Methods: Between 1998 and 2013, we enrolled 131 of 138 eligible patients treated with OK-432 for lymphatic malformations in a retrospective study. The malformations were categorised according to the International Society for the Study of Vascular Anomalies. The outcome was assessed with a clinical examination and a questionnaire.

Results: The lymphatic malformations were localised to the head/neck (60%), the trunk (20%) and the extremities (6%) or involved with more than one region (14%). Patients with microcystic (10%), macrocystic (21%) and mixed lymphatic malformations (69%) underwent a median number of three, two and two injection treatments, respectively. The median age at the first injection was 3.4 years. Good or excellent clinical outcomes were seen in 70% of the patients. The number of injections, previous treatment and lesion localisation, but not time to follow-up and cyst size, predicted the clinical outcome.

Conclusion: OK-432 treatment resulted in a successful outcome in 70% of patients with lymphatic malformations. The long-term outcome was comparable to the short-term outcome.