Primary pulmonary lymphoproliferative neoplasms

Pulmonary lymphoproliferative neoplasms are rare lung tumors and account for <1% of all lung tumors. Among them, primary pulmonary lymphomas (PPL) constitute the majority, which include Non-Hodgkin's lymphoma (NHL) that comprise of mucosa-associated lymphoid tissue lymphoma, diffuse large B-cell lymphomas and other rare types of NHL and lymphomatoid granulomatosis. HL, which arises secondary to contiguous spread from the mediastinum, is the rarest type of PPL. Other entities described within the umbrella of pulmonary lymphoproliferative neoplasms include pleural lymphomas and posttransplant lymphoproliferative disorders (PTLD) - which occurs in the poststem cell and organ transplant patients. These neoplasms although rare, have a favorable prognosis, which does not depend on disease resectability. Moreover, with its nonspecific presentation, diagnosis is challenging, which often leads to delayed diagnosis or misdiagnosis in many cases. Therefore, knowledge of this entity is important for the practicing pulmonologist. This review article aims to describe the clinical presentation, diagnosis and management of primarily the entities within PPL, as well as pleural lymphomas and PTLD.