REFRACTORY CHYLOTHORAX SECONDARY TO WALDENSTROM MACROGLOBULINEMIA

Abstract

TOPIC: Pulmonary Manifestations of Systemic Disease TYPE: Medical Student/Resident Case Reports INTRODUCTION: A chylothorax is defined by the presence of chyle within the pleural cavity. Chylothoraces can be observed as a complication of malignancy; however, Waldenstrom Macroglobulinemia (WM) has rarely been described as a potential cause. We present a case of a refractory chylothorax secondary to WM presenting as a periaortic mass, which eventually required thoracic duct embolization (TDE). CASE PRESENTATION: A 76-year-old male former heavy smoker underwent a low-dose chest CT that showed a large right-sided pleural effusion with suggestion of subcarinal lymphadenopathy. The patient underwent a right-sided thoracentesis, and pleural fluid appeared milky-orange (Figure 1) with triglyceride concentration of 410 mg/dL, diagnostic of a chylothorax. Contrast chest CT revealed a soft tissue mass encasing the descending aorta (Figure 2). Tissue sampling via endobronchial ultrasound (EBUS) demonstrated a monomorphic population of small lymphocytes expressing CD19, CD20, and CD22, while being negative for CD5 and CD10. Additional oncological evaluation including the detection of a MYD88 L265P mutation led to a diagnosis of WM. The patient was started on combination chemoimmunotherapy and had notable tumor response; however, he continued to require high-volume therapeutic thoracentesis (2.5 liters per week). The patient was referred to interventional radiology and underwent successful TDE without complications. Within weeks of thoracic duct embolization, the patient's milky pleural effusion decreased significantly in amount and transitioned to a serosanguinous appearance with a triglyceride concentration of 60 mg/dL. The patient had significant dyspnea relief with decreased frequency of thoracentesis leading to an improved quality-of-life. DISCUSSION: Lymphoma is the most common malignancy-associated cause of a chylothorax. WM is rarely described as a cause in the literature, especially in the setting of a periaortic mass. Malignancy-associated chylothoraces commonly improve with chemotherapy; however, this patient continued to require therapeutic thoracentesis after months of effective chemotherapy. Pedal lymphangiography identified a lymphatic leak within the chest, and TDE was successfully performed without complications. CONCLUSIONS: In patients with a non-traumatic chylothorax, malignancy should be high on the differential diagnosis. Refractory chylothorax can cause serious decrement in quality-of-life due to chronic dyspnea, malnutrition, and recurrent pleural procedures. Early referral for TDE should be considered by chest physicians in patients with refractory chylothorax. REFERENCE #1: Rudrappa M, Paul M. Chylothorax. In: StatPearls. Treasure Island: StatPearls Publishing; 2021 Jan. REFERENCE #2: Otoupalova E, Meka SG, Dogra S, Dalal B. Recurrent chylothorax: a clinical mystery. BMJ Case Rep. 2017;2017:bcr2017220750. Published 2017 Oct 6. doi:10.1136/bcr-2017-220750 DISCLOSURES: No relevant relationships by Ali Bukhari, source=Web Response No relevant relationships by Matthew Koroscil, source=Web Response No relevant relationships by Nathan Mullen, source=Web Response