This is a case of histologically-confirmed mediastinal lymphatic malformation.

Patient first presented with chest pain and difficulty breathing, and a mediastinal mass was detected on chest radiograph and CT. After that, the patient underwent a draining procedure and had a Chamberlain procedure to biopsy the wall, which was positive for lymphatic malformation. However, the cyst kept recurring despite multiple draining and sclerotherapy procedures with doxycycline and the patient continued to be symptomatic. Because of that, the decision was made to excise the lesion thoracoscopically. The procedure was successful, and most of the cyst was removed and the patient has had no recurrence on 8 years follow-up chest radiograph.