Lymphoma - B cell neoplasms - Mediastinal (thymic) large B cell lymphoma

Home Chapter Home Jobs Conferences Fellowships Books

Lymphoma - B cell neoplasms

B cell lymphoma subtypes

Mediastinal (thymic) large B cell lymphoma subtype

Reviewer: Nikhil Sangle, M.D., University of Utah and ARUP Laboratories (see Reviewers page)
Revised: 27 February 2011, last major update February 2011
Copyright: (c) 2001-2011, PathologyOutlines.com, Inc.

Definition
=========================================================================

● A type of diffuse large B cell lymphoma, often presents as antero-superior mediastinal mass, superior vena cava syndrome or tracheobronchial compression
● Absence of lymph node or bone marrow involvement essential to exclude secondary involvement by diffuse large B cell lymphoma

Epidemiology
=========================================================================

● Young adults, 2/3 female

Etiology
=========================================================================

● May derive from thymic medullary B cells or from germinal center (Am J Surg Pathol 2001;25:1277)

Clinical features
=========================================================================

● Aggressive; 50% present with stage 1 or 2 disease
● Poor prognosis, with adjacent thoracic visceral involvement, pleural or pericardial effusion
● 5 year survival is 50%, with relapses to kidney, breast, adrenal cortex, ovary, liver, pancreas, GI

Gross
=========================================================================

● Large, bulky, locally invasive, often fibrotic

Micro description
=========================================================================

● Pleomorphic large cells including centroblasts and immunoblasts with abundant cytoplasm and distinct cell borders
● Oval, cleaved or multilobated nuclei resembling Reed-Sternberg cells
● Also histiocytes, small lymphocytes, sclerosis
● Variable residual thymic tissue

Positive stains
=========================================================================

● CD19, CD20, CD45, CD79a
● Also CD22, bcl6
● Lacks surface immunoglobulin expression (Am J Path 1995;146:735)
● Variable CD10 (33%), CD23, CD30, CD45, TdT
● Rarely beta-hCG (Am J Surg Pathol 1999;23:717)

Negative stains
=========================================================================

● CD3, CD5, CD15, CD21

Molecular
=========================================================================

● Clonal IgH and IgL rearrangements, 9p24 and 2p15 amplification involving REL and BCL11A genes respectively

Differential diagnosis
=========================================================================

● Hodgkin’s lymphoma, lymphoblastic lymphoma, germ cell tumors, thymoma

End of Lymphoma - B cell neoplasms > B cell lymphoma subtypes > Mediastinal (thymic) large B cell lymphoma subtype

This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).