Extramedullary plasmacytoma associated with angiofollicular lymph node hyperplasia.

We report a case of hyaline-vascular type of angiofollicular lymph node hyperplasia involving the left pulmonary lymph nodes and lung. It clinically presented as an obstruction of the left lower lobe main bronchus secondary to the development of an extramedullary plasmacytoma in the lesion. An immunoperoxidase stain revealed a monoclonal IgG-lambda pattern of the tumor, contrasting with the polyclonal plasma cell population of the angiofollicular lymph node hyperplasia. This case demonstrates the neoplastic potential of angiofollicular lymph node hyperplasia.