Whole-Body Diffusion-weighted Imaging in Hodgkin Lymphoma and Diffuse Large B-Cell Lymphoma

Abstract

Whole-body imaging, in particular molecular imaging with fluorine 18 ((18)F)-fluorodeoxyglucose (FDG) positron emission tomography (PET), is essential to management of lymphoma. The assessment of disease extent provided by use of whole-body imaging is mandatory for planning appropriate treatment and determining patient prognosis. Assessment of treatment response allows clinicians to tailor the treatment strategy during therapy if necessary and to document complete remission at the end of treatment. Because of rapid technical developments, such as echo-planar sequences, parallel imaging, multichannel phased-array surface coils, respiratory gating, and moving examination tables, whole-body diffusion-weighted (DW) magnetic resonance (MR) imaging that reflects cell density is now feasible in routine clinical practice. Whole-body DW MR imaging allows anatomic assessment as well as functional and quantitative evaluation of tumor sites by calculation of the apparent diffusion coefficient (ADC). Because of their high cellularity and high nucleus-to-cytoplasm ratio, lymphomatous lesions have low ADC values and appear hypointense on ADC maps. As a result, whole-body DW MR imaging with ADC mapping has become a promising tool for lymphoma staging and treatment response assessment. The authors review their 4 years of experience with 1.5-T and 3-T whole-body DW MR imaging used with (18)F-FDG PET/computed tomography at baseline, interim, and end of treatment in patients with Hodgkin lymphoma and diffuse large B-cell lymphoma and discuss the spectrum of imaging findings and potential pitfalls, limitations, and challenges associated with whole-body DW MR imaging in these patients.

Diffusion-Weighted MRI for Lymphoma Restaging—Response

“…We would also like to emphasize that our DWI criteria for lymphoma involvement are consistent with those recommended in the literature-for instance, see the recent publication by Toledano-Massiah and colleagues (4). Furthermore, a body of published evidence supports the observation that apparent diffusion coefficients (ADC) can differentiate between normal and malignant lymph nodes; lymphomatous nodes even show particularly low ADCs (5).…”

“…Furthermore, a body of published evidence supports the observation that apparent diffusion coefficients (ADC) can differentiate between normal and malignant lymph nodes; lymphomatous nodes even show particularly low ADCs (5). These publications also contain cases that illustrate the visually assessable differences between benign and lymphomatous nodes on DWI (4,5).…”

Targeted PET imaging strategy to differentiate malignant from inflamed lymph nodes in diffuse large B-cell lymphoma

“…To address the systemic nature of DLBCL, whole-body imaging techniques, such as positron emission tomography (PET), computed tomography (CT), and magnetic resonance imaging (MRI), were adopted to improve the diagnosis and disease staging of DLBCL (5). PET imaging is an important imaging modality for diagnosing DLBCL owing to its high sensitivity, short acquisition time, and availability of several imaging probes (6,7).…”

Current whole-body MRI applications in the neurofibromatoses

“…It has been extensively investigated for the detection and staging of visceral and osseous tumors [1][2][3][4][5][6] and is well-suited to tumor syndromes including neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2), and schwannomatosis (SWN), 7-9 as these patients often have a high burden of tumors as well as large tumors that cross anatomic planes (figure). WB-MRI has been used to evaluate tumor burden and to characterize neoplasms in patients with NF syndromes [10][11][12][13][14][15][16][17][18][19][20][21][22][23] and is being used in some clinical trials to evaluate response to therapy (NCT01207687).…”