Does Functional Imaging Distinguish Nodular Lymphocyte-Predominant Hodgkin Lymphoma From T-Cell/Histiocyte-Rich Large B-Cell Lymphoma?

Metabolic tumor volume, cancer cell fraction, and prognosis - the case of T-cell/histiocyte-rich large B-cell lymphoma

T-cell/histiocyte-rich large B-cell lymphoma (THRLBCL) is a rare aggressive lymphoma characterized by a paucity of neoplastic B-cells and a majority of reactive T-cells with or without histiocytes. In the 'Positron Emission Tomography-Guided Therapy of Aggressive Non-Hodgkin Lymphomas' trial (clinicaltrials.gov NCT00554164; EudraCT 2006-001641-33), its frequency was less than 3%. While cancer cell content by quantitative histology was 10-times lower, baseline total metabolic tumor volume (TMTV) by 18-fluorodesoxyglucose positron emission tomography was 10-times higher in THRLBCL than in diffuse large B-cell lymphoma (DLBCL). When THRLBCL and DLBCL populations were matched for TMTV, the survival curves were superimposable. However, when the populations were matched for cancer cell volume by multiplying TMTV by cancer cell fraction, outcome in THRLBCL was worse than in DLBCL. Whether genetic differences between cancer cells, tumor-promoting properties of non-neoplastic cells, or both are responsible for inferior cancer cell volume-related outcome in THRLBCL, remains to be elucidated.

Treatment of Nodular Lymphocyte Hodgkin Lymphoma: The Goldilocks Principle

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.

Multimodality imaging of indolent B cell lymphoma from diagnosis to transformation: what every radiologist should know

Indolent B cell lymphomas are a group of lymphoid malignancies characterized by their potential to undergo histologic transformation to aggressive lymphomas. While different subtypes of indolent B cell lymphomas demonstrate specific clinical and imaging features, histologic transformation can be suspected on cross-sectional imaging when disproportionate lymph node enlargement or new focal lesions in extranodal organs are seen. On PET/CT, transformed indolent lymphoma may show new or increased nodal FDG avidity or new FDG-avid lesions in different organs. In this article, we will (1) review the imaging features of different subtypes of indolent B cell lymphomas, (2) discuss the imaging features of histologic transformation, and (3) propose a diagnostic algorithm for transformed indolent lymphoma. The purpose of this review is to familiarize radiologists with the spectrum of clinical and imaging features of indolent B cell lymphomas and to define the role of imaging in raising concern for transformation and in guiding biopsy for confirmation.

Image-guided radiation therapy in lymphoma management

Image-guided radiation therapy (IGRT) is a process of incorporating imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), Positron emission tomography (PET), and ultrasound (US) during radiation therapy (RT) to improve treatment accuracy. It allows real-time or near real-time visualization of anatomical information to ensure that the target is in its position as planned. In addition, changes in tumor volume and location due to organ motion during treatment can be also compensated. IGRT has been gaining popularity and acceptance rapidly in RT over the past 10 years, and many published data have been reported on prostate, bladder, head and neck, and gastrointestinal cancers. However, the role of IGRT in lymphoma management is not well defined as there are only very limited published data currently available. The scope of this paper is to review the current use of IGRT in the management of lymphoma. The technical and clinical aspects of IGRT, lymphoma imaging studies, the current role of IGRT in lymphoma management and future directions will be discussed.