Abstract No. 17 Diagnosis and Lymphatic Embolization in Managing Plastic Bronchitis: Risk Factors, Outcomes, and Long-Term Follow-up

Lymphatic plastic bronchitis (LPB) is a rare condition with expectoration of bronchial casts that can result in airway obstruction. The cause of LPB is shown to be abnormal lymphatic flow into the bronchial tree. The objective of the study is to summarize our experience in the diagnosis and treatment of LPB. A prospectively collected, retrospective reviewed database identified 57 patients who were referred for the management of LPB. Initially dynamic contrast-enhanced MR lymphangiography (DCMRL) was performed if possible to confirm the diagnosis followed by embolization of the thoracic duct (TD) and/or TD branches. Baseline demographics, comorbidities, DCMRL findings, technical success, immediate and long-term clinical outcomes, and follow-up length were collected. Baseline demographics were summarized in Table 17.1. 42 (73%) patients were obese, 10 (18%) overweight, and 4 (9%) normal BMI. 46/57 patients underwent DCMRL and 11/57 could not tolerate or were contraindicated to DCMRL. In 44/46 patients DCMRL showed abnormal pulmonary lymphatic flow and in 2 patients DCMRL was not diagnostic. TD cannulation was attempted with a technical success rate of 97.8% (56/57). In all 56 patients, TD lymphangiography demonstrated abnormal pulmonary lymphatic flow. TD embolization (TDE) was performed in all 56 patients. Immediate complete clinical success was 98% (55/56). In 1 patient the clinical success was partial, due to concurrent communication between liver lymphatics and bronchial tree and the patient refused repeat procedure. 53 patients were available for long-term follow-up (mean follow-up length: 1265 days; range 31–3364 days). LPB recurred in 8 patients after average 607 days (range 16–3364 days). 5 underwent repeat lymphatic imaging and/or intervention with complete resolution in 4 patients. Median number of TDE procedure was 1 (range 1-4). The overall clinical success rate of patients with long-term follow up was 92.4% (49/53). The incidence of obesity is high in LPB patients suggesting obesity may be a risk factor of LPB. DCMRL can identify abnormal lymphatic pulmonary perfusion to confirm the diagnosis. TDE is an effective treatment in the majority of patients both immediately and at long-term follow up with low incidence of recurrence.