Radiologic Evaluation of Carotid Body Tumor

Transcription

1 March 2006 Radiologic Evaluation of Carotid Body Tumor Mina Le, Harvard Medical School Year III 1

2 A.G. s Story A.G. was a 71-year-old Ethiopian woman who periodically traveled to Boston to visit her daughter. She would frequent the BIDMC for diverse GI issues. One day, a mass was felt on the left side of her neck. 2

3 Ever Larger With Time By radiology and biopsy, the mass in A.G. s neck was found to be a carotid body tumor (paraganglioma). She was advised to have it removed, but opted not to. Over the years, on subsequent visits from Ethiopia to Boston, A.G. s tumor was followed as it slowly grew. We will discuss its appearance on MRI, MRA, CT, CTA. 3

4 Four Ways of Looking at a Tumor Images courtesy of Dr. Lai (1) MRI, August (2) MRA, August

5 Four Ways of Looking at a Tumor Images courtesy of Dr. Lai (3) CT, August (4) CTA, February

6 DDx for a Solid Mass in the Carotid Sheath 1. Lymphadenopathy inflammatory, infectious 2. Traumatic neuroma 3. Benign tumor a. Granular cell tumor (rhabdomyoblastoma) b. Hemangiolymphangioma c. Lipoma d. Nerve sheath tumor (schwannoma, neurofibroma, ganglioneuroma, ganglioblastoma, ganglioneuroblastoma) e. Paraganglioma (glomus jugulare tumor, glomus vagale tumor, carotid body tumor) f. Thyroid and parathyroid tumors (e.g. adenoma) 4. Malignant tumor lymphoma, metastatic lymphadenopathy Reeder MM. Gamuts in Radiology, p

7 DDx for a Solid Mass in the Carotid Sheath 1. Lymphadenopathy inflammatory, infectious 2. Traumatic neuroma 3. Benign tumor a. Granular cell tumor (rhabdomyoblastoma) b. Hemangiolymphangioma c. Lipoma d. Nerve sheath tumor (schwannoma, neurofibroma, ganglioneuroma, ganglioblastoma, ganglioneuroblastoma) e. Paraganglioma (glomus jugulare tumor, glomus vagale tumor, carotid body tumor) f. Thyroid and parathyroid tumors (e.g. adenoma) 4. Malignant tumor lymphoma, metastatic lymphadenopathy Reeder MM. Gamuts in Radiology, p

8 Biopsy Not Recommended The diagnosis of paraganglioma was made in A.G. s case through fine-needle aspiration and cytology. However, when paraganglioma is being considered, biopsy is generally not advised because of the hypervascular nature of these tumors. Imaging is the preferred way to make the diagnosis. Boedeker CC et al. Fam Cancer. 2005;4(1):

9 Menu of Imaging Choices for Diagnosis and Evaluation of a Lateral Neck Mass B-mode sonography + color-coded Doppler sonography Magnetic resonance imaging Computed tomography Digital subtraction angiography Boedeker CC et al. Fam Cancer. 2005;4(1):

10 Merits of Ultrasound Useful as the first step in assessment but not the last. Inexpensive. Non-invasive. Readily available. Boedeker CC et al. Fam Cancer. 2005;4(1):

11 Carotid Body Tumor on Ultrasound Stoeckli SJ et al. Laryngoscope Jan;112(1):

12 Carotid Body Tumor on Ultrasound External carotid artery (anterior) Intratumoral vessels Internal carotid artery (posterior) Stoeckli SJ et al. Laryngoscope Jan;112(1): Internal jugular vein 12

13 Abnormalities on Ultrasound Splaying at the bifurcation: external carotid displaced anteriorly, internal carotid and internal jugular displaced posteriorly Stoeckli SJ et al. Laryngoscope Jan;112(1): Solid, well-defined, hypoechoic, hypervascular mass Tumor-vessel flow direction predominantly upward (red) 13 Boedeker CC et al. Fam Cancer. 2005;4(1):55-59.

14 Differential Diagnosis on Ultrasound Non-paraganglioma masses, e.g. enlarged lymph node: would look similar on B-mode sonography, would not be hypervascular on Doppler. Vagal paraganglioma: can also splay the bifurcation and look hypervascular, but the intratumoral flow signal is directed downward (blue). Stoeckli SJ et al. Laryngoscope Jan;112(1): Boedeker CC et al. Fam Cancer. 2005;4(1):

15 Contribution of MRI MRI helps diagnose paragangliomas by representing their hypervascularity as multiple low-signal areas due to flow void. It is superior to CT scanning in delineating these tumors and in distinguishing them from inflammation and hemorrhage. MRI is also better able to demonstrate the relationship of carotid body tumors to adjacent vascular structures. Mafee MF et al. Radiol Clin North Am Sep;38(5):

16 Carotid Body Tumor on MRI Courtesy of Dr. Lai 16

17 Carotid Body Tumor on MRI Courtesy of Dr. Lai External carotid Internal carotid Carotid body 17

18 Carotid Body Tumor on MRA Courtesy of Dr. Lai 18

19 Carotid Body Tumor on MRA R external carotid R internal carotid R vertebral artery L external carotid L internal carotid L vertebral artery Courtesy of Dr. Lai 19

20 Abnormalities on MRI Mass splaying the internal and external carotid arteries Courtesy of Dr. Lai No definite flow voids High signal on STIR Enhances with gadolinium Courtesy of Dr. Lai 20

21 Most Likely DDx on MRI Courtesy of Dr. Lai Courtesy of Dr. Lai Schwannoma vs. paraganglioma 21

22 Role of CT CT is excellent for defining the exact location of a mass and visualizing its effect on adjacent structures. Combined with a knowledge of anatomy and epidemiology, it can help distinguish among congenital, inflammatory, and neoplastic processes that all result in neck masses. It is quicker and more available than MRI. Reede DL et al. Radiol Clin North Am Mar;22(1):

23 Carotid Body Tumor on CT Courtesy of Dr. Lai 23

24 Carotid Body Tumor on CT ECA ICA IJV Courtesy of Dr. Lai 24

25 Silver AJ et al. Radiol Clin North Am Mar;22(1): Soft-tissue relations Sternocleidomastoid m. Anterior scalene muscles Middle scalene m. Courtesy of Dr. Lai 25

26 Abnormalities On CTA Coarse hypervascularity Incorporation of feeding vessels Courtesy of Dr. Lai Silver AJ et al. Radiol Clin North Am Mar;22(1):

27 Differential Diagnosis on CT Courtesy of Dr. Lai Courtesy of Dr. Lai Schwannoma Lucent Displaces adjacent vessels Paraganglioma Isodense Incorporates adjacent vessels Silver AJ et al. Radiol Clin North Am Mar;22(1):

28 Definitive Confirmation by DSA Digital subtraction angiography provides definitive preoperative characterization. It provides endovascular access for possible embolization; best maps the arterial supply; and, in later phases, visualizes the venous drainage, which allows the surgeon to avoid cutting it until the end, decreasing intraoperative blood loss. Boedeker CC et al. Fam Cancer. 2005;4(1):

29 Angiograms of paragangliomas Carotid body tumor, regular angiogram. Vagal paraganglioma, digital subtraction angiogram. van den Berg R et al. Am J Neuroradiol Jan;21(1):

30 References Boedeker CC, Ridder GJ, Schipper J. Paragangliomas of the head and neck: diagnosis and treatment. Fam Cancer. 2005;4(1): Klatt EC. Carotid body, paraganglioma, low power microscopic. WebPath: The Internet Pathology Laboratory Mafee MF, Raofi B, Kumar A, Muscato C. Glomus faciale, glomus jugulare, glomus tympanicum, glomus vagale, carotid body tumors, and simulating lesions. Radiol Clin North Am Sep;38(5): Reede DL, Whelan MA, Bergeron RT. CT of the soft tissue structures of the neck. Radiol Clin North Am Mar;22(1): Reeder MM. Reeder and Felson s Gamuts in Radiology: Comprehensive Lists of Roentgen Differential Diagnosis, 4 th ed. New York: Springer-Verlag New York, Inc., Silver AJ, Ganti SR, Hilal SK. The carotid region: normal and pathologic anatomy on CT. Radiol Clin North Am Mar;22(1): Stoeckli SJ, Schuknecht B, Alkadhi H, Fisch U. Evaluation of paragangliomas presenting as a cervical mass on color-coded Doppler sonography. Laryngoscope Jan;112(1): Van den Berg R et al. Vascularization of head and neck paragangliomas: comparison of three MR angiographic techniques with digital subtraction angiography. Am J Neuroradiol Jan;21(1):

31 Acknowledgments Dr. Ken Lai Dr. Katherine Krajewski Pamela Lepkowski Dr. Gillian Lieberman Larry Barbaras, webmaster 31