Masquerading as an Interstitial Lung Disease: Intravascular Large B-Cell Lymphoma With Prominent Neo-Angiogenesis

Intravascular large B-cell lymphoma forms a rare entity that may mimic disease symptoms according to the affected sites. It is characterized by the presence of large atypical lymphoid B cells restricted to intravascular spaces, especially capillaries. We present a 65-year-old man who presented with a concurrent intravascular large B-cell lymphoma and Waldenström macroglobulinemia with prominent pulmonary symptoms masquerading as a hypersensitivity pneumonitis. A subsequent surgical lung biopsy illustrated peribronchial and interstitial nodular aggregates which consisted of numerous capillary structures filled with neoplastic B lymphocytes. This report hints toward potential induction of prominent neo-angiogenesis by intravascular large B-cell lymphoma, with development of intrapulmonary nodular aggregates mimicking interstitial lung disease.