[Waldenström macroglobulinemia complicated with chylothorax].

An 81-year-old male had been diagnosed with Waldenström macroglobulinemia (WM) eight years previously and had thus been administered appropriate treatment. Left chylothorax later developed at 3 years and 8 months after the initial diagnosis. He was hospitalized with severe anemia, general fatigue, and appetite loss one year prior to this presentation and died due to a severe fungal infection. Autopsy revealed the presence of 1,300 ml chylothorax and infiltration of lymphoplasmacytic lymphoma (LPL) cells throughout his entire body. LPL cells were found to have invaded the excitation conducting system in the heart. In an evaluation of a resected lung tissue specimen of pneumothorax, subpleural infiltrated lymphoid cells were observed to show immunohistochemical positivity for IgM and bcl-2. Although these lymphoid cells were initially considered to be non-neoplastic lymphocytes, they were later determined to be LPL cells, which thus induced dilatation and proliferation of the lymph vessels. Chylothorax complications in patients with WM are rare events and only six such cases have so far been reported. The present case is considered to be an instructive one in which autopsy suggested the invasion of LPL cells to be involved in the development of arrhythmia, pneumothorax, and chylothorax before death.