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18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Management of Aggressive Non-Hodgkin's B-Cell Lymphoma.

Shelly MJ, McDermott S, O'Connor OJ, Blake MA - ISRN Hematol (2012)

Bottom Line: 18-Fluorodeoxyglucose (FDG-PET/CT) is an established imaging modality that has been proven to be of benefit in the management of aggressive B-cell non-Hodgkin's lymphoma, such as diffuse large B-cell lymphoma and advanced stage follicular lymphoma.The combination of anatomic and functional imaging afforded by FDG-PET/CT has led to superior sensitivity and specificity in the primary staging, restaging, and assessment of response to treatment of hematological malignancies when compared to FDG-PET and CT alone.The use of FDG-PET/CT for posttreatment surveillance imaging remains controversial, and further study is needed to ascertain whether this modality is cost effective and appropriate for use in this setting.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Massachusetts General Hospital, Boston, MA 02114, USA.

ABSTRACT
18-Fluorodeoxyglucose (FDG-PET/CT) is an established imaging modality that has been proven to be of benefit in the management of aggressive B-cell non-Hodgkin's lymphoma, such as diffuse large B-cell lymphoma and advanced stage follicular lymphoma. The combination of anatomic and functional imaging afforded by FDG-PET/CT has led to superior sensitivity and specificity in the primary staging, restaging, and assessment of response to treatment of hematological malignancies when compared to FDG-PET and CT alone. The use of FDG-PET/CT for posttreatment surveillance imaging remains controversial, and further study is needed to ascertain whether this modality is cost effective and appropriate for use in this setting.

No MeSH data available.


Related in: MedlinePlus

Coronal PET maximum intensity projection (MIP) image (a) displaying foci of increased radiotracer uptake bilaterally in the neck in a patient with treated DLBSL. The corresponding coronal CT (b) and fused FDG-PET/CT (c) demonstrate no abnormality and the areas with increased FDG uptake correspond to regions of fat density (arrows). This is the characteristic appearance of hypermetabolic brown fat on FDG-PET/CT.
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fig1: Coronal PET maximum intensity projection (MIP) image (a) displaying foci of increased radiotracer uptake bilaterally in the neck in a patient with treated DLBSL. The corresponding coronal CT (b) and fused FDG-PET/CT (c) demonstrate no abnormality and the areas with increased FDG uptake correspond to regions of fat density (arrows). This is the characteristic appearance of hypermetabolic brown fat on FDG-PET/CT.

Mentions: The management of lymphoma depends on histologic subtype, stage, and grade. HL and the more aggressive forms of NHL share similar radiologic imaging patterns with the near universal use of combined FDG-PET/CT for assessment [6, 7]. Combined FDG-PET/CT is now considered the most accurate tool for diagnosis, assessment of treatment response, and prognosis in patients with aggressive NHL [8]. There are a number of caveats that one must be aware of when interpreting FDG-PET/CT in the setting of lymphoma. Certain subtypes of B-cell lymphoma, particularly extranodal marginal zone lymphoma and peripheral T-cell lymphoma, display variable FDG uptake and can also be sometimes difficult to identify on contrast enhanced CT (CECT) [9]. In these cases, a baseline FDG-PET/CT is essential to facilitate meaningful interpretation of posttreatment imaging in terms of treatment response. A number of subtypes of lymphoma may be difficult or almost impossible to detect with FDG-PET/CT such as primary CNS lymphoma, testicular lymphoma, and gastric lymphoma. The normal brain and testes demonstrate intense FDG avidity and against this high background FDG activity, primary CNS and testicular lymphoma may be very difficult to detect without adjusting the image intensity thresholds [10]. Gastric lymphoma displays an extremely variable FDG uptake that may be difficult or impossible to differentiate from normal physiologic FDG uptake in the gastric mucosa [11]. Diffuse or heterogeneous bone marrow uptake of radiotracer in a pretreatment scan should not immediately suggest bone marrow involvement by lymphoma as this pattern of uptake can be seen in reactive myeloid hyperplasia [5, 12]. Focally increased FDG uptake can also be seen in the musculoskeletal system due to trauma, muscle activity, and degenerative change in synovial joints and also in brown fat which has a higher basal metabolic rate than adjacent tissues and may be mistaken for a lymphoma deposit. However, brown fat has a characteristic distribution and its detection is usually reasonably straightforward on FDG-PET/CT [13] (Figure 1). If patients with lymphoma are treated with granulocyte-colony stimulating factors, their bone marrow may show a diffuse increase in FDG uptake. It is very important to recognize the aforementioned pitfalls to avoid false-positive interpretation of FDG-PET/CT scans and hence potential overstaging of patients.


18-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Management of Aggressive Non-Hodgkin's B-Cell Lymphoma.

Shelly MJ, McDermott S, O'Connor OJ, Blake MA - ISRN Hematol (2012)

Coronal PET maximum intensity projection (MIP) image (a) displaying foci of increased radiotracer uptake bilaterally in the neck in a patient with treated DLBSL. The corresponding coronal CT (b) and fused FDG-PET/CT (c) demonstrate no abnormality and the areas with increased FDG uptake correspond to regions of fat density (arrows). This is the characteristic appearance of hypermetabolic brown fat on FDG-PET/CT.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3313577&req=5

fig1: Coronal PET maximum intensity projection (MIP) image (a) displaying foci of increased radiotracer uptake bilaterally in the neck in a patient with treated DLBSL. The corresponding coronal CT (b) and fused FDG-PET/CT (c) demonstrate no abnormality and the areas with increased FDG uptake correspond to regions of fat density (arrows). This is the characteristic appearance of hypermetabolic brown fat on FDG-PET/CT.
Mentions: The management of lymphoma depends on histologic subtype, stage, and grade. HL and the more aggressive forms of NHL share similar radiologic imaging patterns with the near universal use of combined FDG-PET/CT for assessment [6, 7]. Combined FDG-PET/CT is now considered the most accurate tool for diagnosis, assessment of treatment response, and prognosis in patients with aggressive NHL [8]. There are a number of caveats that one must be aware of when interpreting FDG-PET/CT in the setting of lymphoma. Certain subtypes of B-cell lymphoma, particularly extranodal marginal zone lymphoma and peripheral T-cell lymphoma, display variable FDG uptake and can also be sometimes difficult to identify on contrast enhanced CT (CECT) [9]. In these cases, a baseline FDG-PET/CT is essential to facilitate meaningful interpretation of posttreatment imaging in terms of treatment response. A number of subtypes of lymphoma may be difficult or almost impossible to detect with FDG-PET/CT such as primary CNS lymphoma, testicular lymphoma, and gastric lymphoma. The normal brain and testes demonstrate intense FDG avidity and against this high background FDG activity, primary CNS and testicular lymphoma may be very difficult to detect without adjusting the image intensity thresholds [10]. Gastric lymphoma displays an extremely variable FDG uptake that may be difficult or impossible to differentiate from normal physiologic FDG uptake in the gastric mucosa [11]. Diffuse or heterogeneous bone marrow uptake of radiotracer in a pretreatment scan should not immediately suggest bone marrow involvement by lymphoma as this pattern of uptake can be seen in reactive myeloid hyperplasia [5, 12]. Focally increased FDG uptake can also be seen in the musculoskeletal system due to trauma, muscle activity, and degenerative change in synovial joints and also in brown fat which has a higher basal metabolic rate than adjacent tissues and may be mistaken for a lymphoma deposit. However, brown fat has a characteristic distribution and its detection is usually reasonably straightforward on FDG-PET/CT [13] (Figure 1). If patients with lymphoma are treated with granulocyte-colony stimulating factors, their bone marrow may show a diffuse increase in FDG uptake. It is very important to recognize the aforementioned pitfalls to avoid false-positive interpretation of FDG-PET/CT scans and hence potential overstaging of patients.

Bottom Line: 18-Fluorodeoxyglucose (FDG-PET/CT) is an established imaging modality that has been proven to be of benefit in the management of aggressive B-cell non-Hodgkin's lymphoma, such as diffuse large B-cell lymphoma and advanced stage follicular lymphoma.The combination of anatomic and functional imaging afforded by FDG-PET/CT has led to superior sensitivity and specificity in the primary staging, restaging, and assessment of response to treatment of hematological malignancies when compared to FDG-PET and CT alone.The use of FDG-PET/CT for posttreatment surveillance imaging remains controversial, and further study is needed to ascertain whether this modality is cost effective and appropriate for use in this setting.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Massachusetts General Hospital, Boston, MA 02114, USA.

ABSTRACT
18-Fluorodeoxyglucose (FDG-PET/CT) is an established imaging modality that has been proven to be of benefit in the management of aggressive B-cell non-Hodgkin's lymphoma, such as diffuse large B-cell lymphoma and advanced stage follicular lymphoma. The combination of anatomic and functional imaging afforded by FDG-PET/CT has led to superior sensitivity and specificity in the primary staging, restaging, and assessment of response to treatment of hematological malignancies when compared to FDG-PET and CT alone. The use of FDG-PET/CT for posttreatment surveillance imaging remains controversial, and further study is needed to ascertain whether this modality is cost effective and appropriate for use in this setting.

No MeSH data available.


Related in: MedlinePlus