IMAGING VIGNETTE PET-MR Imaging in Evaluation of Cardiac and Paracardiac Masses With Histopathologic Correlation Kavitha Yaddanapudi, MD,* Richard Brunken, MD,y Carmela D. Tan, MD,z E. Rene Rodriguez, MD,z Michael A. Bolen, MD* CARDIAC TUMORS ARE INFREQUENT, AND MANAGEMENT STRATEGY DEPENDS ON WHETHER THE TUMOR is benign or malignant, as well as its location within the heart. Imaging characteristics aid in prognostication and direct management. Magnetic resonance imaging (MRI) is a useful tool providing multiplanar imaging, wide field of view, and inherent tissue characterization; however, MRI alone often cannot predict whether a tumor is benign or malignant. 18 F-fluorodeoxyglucose positron emission tomography (PET) imaging may help identify malignant lesions, as hypermetabolism is a marker for malignant potential. A combined approach that uses the relative strengths of both MRI and PET imaging could potentially yield extensive anatomic and metabolic information about cardiac masses. We present 6 cases (Figures 1 to 6) that demonstrate the potential utility of fused MRI and PET imaging in the assessment of suspected cardiac masses, with corresponding histopathology. We utilized basic fusion and co-registration software to create the fused PET–MRI image from separately acquired MRI and PET images. Fused PET–MRI may provide increased confidence in decision making in diagnosis of cardiac masses, as well as a means of re-evaluation. Images may be acquired concurrently or fused after separate acquisitions, as in this series. This approach requires investigation in larger cohorts to further delineate its clinical role. From the *Imaging Institute, Cleveland Clinic, Cleveland, Ohio; yDepartment of Nuclear Medicine, Cleveland Clinic, Cleveland, Ohio; and the zDepartment of Pathology, Cleveland Clinic, Cleveland, Ohio. The authors have reported that they have no relationships relevant to the contents of this paper to disclose. Manuscript received February 11, 2015; revised manuscript received April 7, 2015, accepted April 9, 2015. JACC: CARDIOVASCULAR IMAGING VOL. 9, NO. 1, 2016 ª 2016 BY THE AMERICAN COLLEGE OF CARDIOLOGY FOUNDATION ISSN 1936-878X/$36.00 PUBLISHED BY ELSEVIER http://dx.doi.org/10.1016/j.jcmg.2015.04.028
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IMAGING VIGNETTE
PET-MR Imaging in Evaluationof Cardiac and Paracardiac MassesWith Histopathologic Correlation
Kavitha Yaddanapudi, MD,* Richard Brunken, MD,y Carmela D. Tan, MD,z E. Rene Rodriguez, MD,zMichael A. Bolen, MD*
CARDIAC TUMORS ARE INFREQUENT, AND MANAGEMENT STRATEGY DEPENDS ON WHETHER THE TUMOR
is benign or malignant, as well as its location within the heart. Imaging characteristics aid in prognosticationand direct management. Magnetic resonance imaging (MRI) is a useful tool providing multiplanar imaging,wide field of view, and inherent tissue characterization; however, MRI alone often cannot predict whether atumor is benign or malignant. 18F-fluorodeoxyglucose positron emission tomography (PET) imaging may helpidentify malignant lesions, as hypermetabolism is a marker for malignant potential. A combined approach thatuses the relative strengths of both MRI and PET imaging could potentially yield extensive anatomic andmetabolic information about cardiac masses.
We present 6 cases (Figures 1 to 6) that demonstrate the potential utility of fused MRI and PET imaging in theassessment of suspected cardiac masses, with corresponding histopathology. We utilized basic fusion andco-registration software to create the fused PET–MRI image from separately acquired MRI and PET images.
Fused PET–MRI may provide increased confidence in decision making in diagnosis of cardiac masses, as wellas a means of re-evaluation. Images may be acquired concurrently or fused after separate acquisitions, as inthis series. This approach requires investigation in larger cohorts to further delineate its clinical role.
From the *Imaging Institute, Cleveland Clinic, Cleveland, Ohio; yDepartment of Nuclear Medicine, Cleveland Clinic, Cleveland,
Ohio; and the zDepartment of Pathology, Cleveland Clinic, Cleveland, Ohio. The authors have reported that they have no
relationships relevant to the contents of this paper to disclose.
Manuscript received February 11, 2015; revised manuscript received April 7, 2015, accepted April 9, 2015.
FIGURE 1 A 37-Year-Old Man With Chest Pain and Myalgia, Work-Up Negative for Myocardial Infarction
Magnetic resonance imaging (MRI) demonstrated a heterogeneously enhancing mass (pink arrow) inseparable from the right atrial wall on
MRI: (A) dark blood image, (B) T1 post-contrast image, and (C) delayed post-contrast inversion recovery image. Fused positron emission
tomography–MRI images (PET-MRI) (D, green arrow) with 18F-fluorodeoxyglucose uptake in peripheral non-necrotic portion of the mass with
maximum standardized uptake value of 6.6 were suggestive of malignant neoplasm, with liver metastases suspected. Biopsy of liver mass
showed a vascular tumor with endothelial lining that exhibited cellular atypia and papillary tufting consistent with low-grade angiosarcoma (E).
FIGURE 2 A 48-Year-Old Man With
History of Chest Discomfort
Computed tomography of chest (A, pink
arrow) revealed a paracardiac mass that
consisted of soft-tissue serpiginous
structures and phleboliths. Cardiac
magnetic resonance demonstrated the
mass, with indistinct tissue borders
adjacent to left ventricle (B, pink arrow).
There was no 18F-fluorodeoxyglucose
uptake (C, green arrow), consistent with
a benign mass. Surgical biopsy and par-
tial en bloc resection revealed a lesion
composed of variably sized vessels
infiltrating through fat (D) that were
histologically benign. Three-year follow-
up imaging revealed no significant
change in the mass, with the patient
reporting only mild residual pain at the
site of the thoracotomy.
J A C C : C A R D I O V A S C U L A R I M A G I N G , V O L . 9 , N O . 1 , 2 0 1 6 Yaddanapudi et al.J A N U A R Y 2 0 1 6 : 8 2 – 5 Fused PET-MRI in Cardiac Masses
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FIGURE 3 A 52-Year-Old Man With Multiple Cardioembolic Events Despite Anticoagulation
Echocardiogram demonstrated a 2-cm mitral annulus mass with suspected friability (D). Magnetic resonance imaging (MRI) revealed the mass
to be of intermediate signal intensity on steady-state free precession imaging (A, pink arrow), with enhancement on delayed post-contrast
images (B, pink arrow). Fused MRI–positron emission tomography imaging revealed intense uptake (C, green arrow). A decision was made to
proceed with surgery, including decalcification of the posterior leaflet of mitral valve and repair. Surgical pathology revealed organizing
thrombus with neovascularization, and chronic inflammation (E). No further embolic events have been observed.
FIGURE 4 A 49-Year Old Woman With Chest Pain
A 5 � 7 cm mass was identified abutting the right atrium in the atrioventricular groove region (A, pink arrow) (dark blood image), with no
invasive features. The lesion was diffusely hyperintense on T2-weighted fat-saturated dark blood images (B, pink arrow) and on steady-state
free precession images (C, pink arrow). Mild 18F-fluorodeoxyglucose uptake on the fused positron emission tomography–cardiac magnetic
resonance images with a maximum standardized uptake value of 2.7, comparable to blood pool, suggestive of the benign nature of the mass
(D, blue arrow). Surgical biopsy revealed benign hemangioma (E). At 1-year follow-up, the mass was stable in appearance on cardiac magnetic
resonance.
Yaddanapudi et al. J A C C : C A R D I O V A S C U L A R I M A G I N G , V O L . 9 , N O . 1 , 2 0 1 6
Fused PET-MRI in Cardiac Masses J A N U A R Y 2 0 1 6 : 8 2 – 5
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FIGURE 5 A 22-Year-Old Man With Synovial
Sarcoma of Right Ventricle Treated With Surgical
Resection and Chemotherapy
On surveillance imaging (3 years after resection), a
large lobular mass was noted, inseparable from the
right atrium, with intermediate signal intensity on
dark blood images (A, pink arrow), and hyperintense
on edema-sensitive inversion recovery images (B).
On fused positron emission tomography–cardiac
magnetic resonance images, the entire mass had
increased 18F-fluorodeoxyglucose uptake and a
maximum standardized uptake value of 7.8, consis-
tent with recurrence (C, green arrow). Reoperation
was performed, and surgical pathology demon-
strated undifferentiated spindled cells harboring a
translocation in the SYT gene, diagnostic of synovial
sarcoma (D).
FIGURE 6 A 63-Year-Old Man With Intermittent Dyspnea
Magnetic resonance imaging (MRI) depicted a mass in
the aortopulmonary groove and right ventricular
outflow tract, with intermediate signal intensity on dark
blood (A, pink arrow) and diffuse enhancement (B, pink
arranged in nests (left) positive for synaptophysin
(right), consistent with paraganglioma. Genetic testing
revealed an SDHB mutation, and the patient was treated
with debulking and chemotherapy.
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REPRINT REQUESTS AND CORRESPONDENCE: Dr. Kavitha Yaddanapudi, Department of Radiology, HSCtower, Level 4, Room 120, Stony Brook, New York 11794-8460. E-mail: [email protected].
