IMAGES THAT TEACH Incidentally found giant thymomas by SPECT myocardial perfusion imaging Ayman A. Farag, MD,a and Fadi G. Hage, MD, FASH, FACCa,b a
Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL b Section of Cardiology, Birmingham Veterans Affairs Medical Center, Birmingham, AL
doi:10.1007/s12350-014-0028-9
CASE 1 PRESENTATION A 70-year-old man with hypertension presented for evaluation of intermittent chest pain. The physical examination was unremarkable except for morbid obesity. He underwent regadenoson gated Tc-99m sestamibi SPECT. The rest and stress ECGs were normal. The SPECT images showed normal myocardial perfusion with a left ventricular ejection fraction of 72% (Figure 1). There was a very large extracardiac mass in the anterior mediastinum seen on the tomographic and the raw rotating images (Figures 1, 2). Computed tomography confirmed the presence of a giant mass in the anterior mediastinum (Figure 3). The patient underwent left thoracotomy with excision of the mass. Histologic analysis revealed a 9.5 9 8 9 5.5 cm spindle cell tumor-rich in lymphocytes consistent with AB thymoma (Figure 4). The mass did not invade any of the surrounding structures. Adjuvant radiotherapy was deemed unnecessary and the patient did well postoperatively.
ECGs were normal. The stress SPECT images showed normal myocardial perfusion and left ventricular systolic function. A giant mass was seen in the mediastinum on the rotating raw images (Figure 5). Computed tomography confirmed the presence of a 11.6 9 7.8 cm irregular mass anterior to the right heart and extending to the superior mediastinum (Figure 6). The patient subsequently underwent bronchoscopy that ruled out lung cancer followed by anterior mediastinotomy (Chamberlain procedure) with tissue biopsy that revealed spindle cell tumor-rich in lymphocytes consistent with AB thymoma. She is being treated with chemotherapy to reduce the tumor mass prior to possible surgical resection. Thymoma is known to be one of the most common anterior mediastinal tumors. Surgical excision is the treatment of choice. Thymomas have been
CASE 2 PRESENTATION A 66-year-old obese woman with hypertension, hyperlipidemia, chronic obstructive pulmonary disease, atrial fibrillation, and active tobacco smoker presented with episodic chest pain and dyspnea on exertion for several weeks. The physical examination was unremarkable. She underwent regadenoson gated technetium-99m sestamibi SPECT. The rest and stress Reprint requests: Ayman A. Farag, MD, Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, THT 311, 1900 University BLVD, Birmingham, AL 35294; [email protected] J Nucl Cardiol 2015;22:385–7. 1071-3581/$34.00 Copyright Ó 2014 American Society of Nuclear Cardiology.
Figure 1. Case 1. Stress Tc-99m sestamibi SPECT images showing normal myocardial perfusion. There is an extracardiac mass seen in the short-axis slices (arrows). 385
386
Farag and Hage Incidental finding of thymoma by SPECT
Journal of Nuclear CardiologyÒ March/April 2015
Figure 2. Case 1. The raw anterior planar images show an extracardiac mass in the anterior mediastinum (arrow). Figure 3. Case 1. Contrast-enhanced chest CT shows a large mass anterior to the ascending aorta in the anterior mediastinum (arrow).
Figure 4. Case 1. High power microscopy of the excised mass showing spindle cells (left panel) and spindle cells mixed with lymphocytic cells (middle panel) consistent with type AB thymoma. The low power microscopy demonstrates no extracapsular invasion (right panel).
described as incidental findings with technetium tracers or thallium-201 but to our knowledge these cases are the largest reported in the literature (previously reported thymomas which were incidentally detected
on cardiac SPTECT sized between 5 and 9 cm).1-7 The rotating images are helpful although in one of our patients the mass was evident on the SPECT images as well.
Journal of Nuclear CardiologyÒ Volume 22, Number 2;385–7
Farag and Hage Incidental finding of thymoma by SPECT
387
References
Figure 5. Case 2. The raw anterior planar images show an extracardiac mass in the anterior mediastinum extending to the lower right lung field (arrow).
Figure 6. Case 2. CT chest without contrast shows a large irregular mediastinal mass anterior to the right heart and extending into the superior mediastinum, measuring 11.6 9 7.8 cm (arrow).
1. AlJaroudi W, Dubovsky EV, Iskandrian AE. Extracardiac incidental findings. In: Iskandrian E, Garcia V, editors. Atlas of nuclear cardiology: Imaging companion to Braunwald’s heart disease, vol. 9. Philadelphia: Elsevier Inc.; 2012. p. 322-46. 2. Tseng JC, Tsai MF, Chang LC, Hua CC. Incidental detection of an invasive thymoma during thallium-201 imaging for coronary artery disease. Chang Gung Med J 2004;27:138-42. 3. Casson AG, Kirsh JC. Thymoma found during routine cardiac imaging. Can J Surg 1996;39:186-7. 4. Abo-Salem E, Gerson M. Mediastinal thymoma diagnosed with Tc99m tetrofosmin SPECT myocardial perfusion imaging. J Nucl Cardiol 2014. doi:10.1007/s12350-014-9947-8. 5. Aydın F, Budak ES, Dertsiz L, Belgi A, Arslan G, Gu¨ngo¨r F. Incidental detection of a benign thymoma on Tc-99m MIBI myocardial perfusion study. Mol Imaging Radionucl Therapy 2011;20:73-5. doi:10.4274/MIRT.019513. 6. Mohan P, Pathak V, Joshi P, Baruah B, Bal S. Incidental detection of mediastinal thymoma during Tc-99m tetrofosmin myocardial perfusion imaging. IJNM 2006;21:41-2. 7. Serra Arbeloa P, Lancha Hernandez C. Hallazgo casual de un timoma en un estudio de perfusio´n mioca´rdicacon 99mTc-tetrofosmin. Rev Esp Med Nucl 2008;27:279-80.
Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL b Section of Cardiology, Birmingham Veterans Affairs Medical Center, Birmingham, AL
doi:10.1007/s12350-014-0028-9
CASE 1 PRESENTATION A 70-year-old man with hypertension presented for evaluation of intermittent chest pain. The physical examination was unremarkable except for morbid obesity. He underwent regadenoson gated Tc-99m sestamibi SPECT. The rest and stress ECGs were normal. The SPECT images showed normal myocardial perfusion with a left ventricular ejection fraction of 72% (Figure 1). There was a very large extracardiac mass in the anterior mediastinum seen on the tomographic and the raw rotating images (Figures 1, 2). Computed tomography confirmed the presence of a giant mass in the anterior mediastinum (Figure 3). The patient underwent left thoracotomy with excision of the mass. Histologic analysis revealed a 9.5 9 8 9 5.5 cm spindle cell tumor-rich in lymphocytes consistent with AB thymoma (Figure 4). The mass did not invade any of the surrounding structures. Adjuvant radiotherapy was deemed unnecessary and the patient did well postoperatively.
ECGs were normal. The stress SPECT images showed normal myocardial perfusion and left ventricular systolic function. A giant mass was seen in the mediastinum on the rotating raw images (Figure 5). Computed tomography confirmed the presence of a 11.6 9 7.8 cm irregular mass anterior to the right heart and extending to the superior mediastinum (Figure 6). The patient subsequently underwent bronchoscopy that ruled out lung cancer followed by anterior mediastinotomy (Chamberlain procedure) with tissue biopsy that revealed spindle cell tumor-rich in lymphocytes consistent with AB thymoma. She is being treated with chemotherapy to reduce the tumor mass prior to possible surgical resection. Thymoma is known to be one of the most common anterior mediastinal tumors. Surgical excision is the treatment of choice. Thymomas have been
CASE 2 PRESENTATION A 66-year-old obese woman with hypertension, hyperlipidemia, chronic obstructive pulmonary disease, atrial fibrillation, and active tobacco smoker presented with episodic chest pain and dyspnea on exertion for several weeks. The physical examination was unremarkable. She underwent regadenoson gated technetium-99m sestamibi SPECT. The rest and stress Reprint requests: Ayman A. Farag, MD, Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, THT 311, 1900 University BLVD, Birmingham, AL 35294; [email protected] J Nucl Cardiol 2015;22:385–7. 1071-3581/$34.00 Copyright Ó 2014 American Society of Nuclear Cardiology.
Figure 1. Case 1. Stress Tc-99m sestamibi SPECT images showing normal myocardial perfusion. There is an extracardiac mass seen in the short-axis slices (arrows). 385
386
Farag and Hage Incidental finding of thymoma by SPECT
Journal of Nuclear CardiologyÒ March/April 2015
Figure 2. Case 1. The raw anterior planar images show an extracardiac mass in the anterior mediastinum (arrow). Figure 3. Case 1. Contrast-enhanced chest CT shows a large mass anterior to the ascending aorta in the anterior mediastinum (arrow).
Figure 4. Case 1. High power microscopy of the excised mass showing spindle cells (left panel) and spindle cells mixed with lymphocytic cells (middle panel) consistent with type AB thymoma. The low power microscopy demonstrates no extracapsular invasion (right panel).
described as incidental findings with technetium tracers or thallium-201 but to our knowledge these cases are the largest reported in the literature (previously reported thymomas which were incidentally detected
on cardiac SPTECT sized between 5 and 9 cm).1-7 The rotating images are helpful although in one of our patients the mass was evident on the SPECT images as well.
Journal of Nuclear CardiologyÒ Volume 22, Number 2;385–7
Farag and Hage Incidental finding of thymoma by SPECT
387
References
Figure 5. Case 2. The raw anterior planar images show an extracardiac mass in the anterior mediastinum extending to the lower right lung field (arrow).
Figure 6. Case 2. CT chest without contrast shows a large irregular mediastinal mass anterior to the right heart and extending into the superior mediastinum, measuring 11.6 9 7.8 cm (arrow).
1. AlJaroudi W, Dubovsky EV, Iskandrian AE. Extracardiac incidental findings. In: Iskandrian E, Garcia V, editors. Atlas of nuclear cardiology: Imaging companion to Braunwald’s heart disease, vol. 9. Philadelphia: Elsevier Inc.; 2012. p. 322-46. 2. Tseng JC, Tsai MF, Chang LC, Hua CC. Incidental detection of an invasive thymoma during thallium-201 imaging for coronary artery disease. Chang Gung Med J 2004;27:138-42. 3. Casson AG, Kirsh JC. Thymoma found during routine cardiac imaging. Can J Surg 1996;39:186-7. 4. Abo-Salem E, Gerson M. Mediastinal thymoma diagnosed with Tc99m tetrofosmin SPECT myocardial perfusion imaging. J Nucl Cardiol 2014. doi:10.1007/s12350-014-9947-8. 5. Aydın F, Budak ES, Dertsiz L, Belgi A, Arslan G, Gu¨ngo¨r F. Incidental detection of a benign thymoma on Tc-99m MIBI myocardial perfusion study. Mol Imaging Radionucl Therapy 2011;20:73-5. doi:10.4274/MIRT.019513. 6. Mohan P, Pathak V, Joshi P, Baruah B, Bal S. Incidental detection of mediastinal thymoma during Tc-99m tetrofosmin myocardial perfusion imaging. IJNM 2006;21:41-2. 7. Serra Arbeloa P, Lancha Hernandez C. Hallazgo casual de un timoma en un estudio de perfusio´n mioca´rdicacon 99mTc-tetrofosmin. Rev Esp Med Nucl 2008;27:279-80.
