Primary pulmonary lymphoproliferative neoplasms

Abstract

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.

Keywords: Acquired immune-deficiency syndrome; lymphoma; primary pulmonary lymphoma; rare lung neoplasms.

Figure 1

Bronchoscopy showing secondary involvement and encroachment into right mainstem bronchus from systemic diffuse large B cell lymphoma

Figure 2

Computed tomography scan showing right lower lobe mass (a) with mediastinal adenopathy, as secondary involvement from mantle cell lymphoma. (b) Cyclin D 1 positivity on tumor cells from transbronchial biopsy, confirming Mantle cell lymphoma

Figure 3

Computed tomography with mass in the right lower lobe and pleural effusion of 2 years duration. (a) The patient underwent thoracotomy and surgical excision, which demonstrated large sheets of CD 20 positive B cells (b) and confirmed as mucosa associated lymphoid tissue-primary pulmonary lymphomas. (c) H and E, under high power (×400) showing large sheets of B cells. The patient was lost to follow up

Figure 4

Computed tomography scan showing large necrotic opacity in the right upper lobe (a). Bronchoscopy with transbronchial lung biopsy revealing large population of B cells. (b) Large B cells in clusters consistent with diffuse large B-cell Lymphoma. The patient was started on cyclophosphamide, doxorubicin, vincristine and prednisone with remission achieved and is doing well at 2 years after follow-up (H and E, ×400)

Figure 5

Computed tomography scan showing bilateral pleural effusions in a patient with human immunodeficiency virus/acquired immune-deficiency syndrome (a). Thoracentesis done subsequently revealed large B cells, (b) Diff-Quik stain on cytological evaluation revealing rare large lymphoid cells (×600) confirming primary effusion lymphoma