|Patient: 52 year old male|
|History: 52-year-old man with chest pain, dyspnea, and nausea. He had a myocardial infarction in March 2007. He is status post stent placement. Evaluate for myocardial ischemia|
|Findings: RADIOPHARMACEUTICAL: 2.7 mCi Tl-201 chloride i.v. and 21.5 mCi Tc-99m sestamibi i.v.|
Normal myocardial perfusion. However, there is a focus of increased activity that is present near the right hilum, seen on the projection images as well as the SPECT images. A recent chest radiograph showed no definite correlate. Further evaluation with CT examination was recommended.
|DDx: Tracer uptake in an anterior mediastinal mass. Thymoma or lymphoma are most likely.|
|Diagnosis: CT demonstrated a 4 cm enhancing anterior mediastinal mass just to the right of midline and deep to the right internal mammary artery. There are small regions of low-attenuation centrally within the mass, which may reflect necrosis. This lesion is most consistent with a thymoma. An alternative and less likely diagnosis is lymphoma.|
To date, no pathologic confirmation has been obtained.
General Discussion: |
Specific Discussion: |
Extracardiac focal uptake is best visualized by evaluating cine images.Uptake of both Tl-201 and Tc-99m sestamibi in both benign and malignant thymomas has been previously described. A single focus of radiotracer uptake on Tl-201 images with no matching lesion on the Tc-99m study is suggestive of poorly-differentiated thymoma. In contrast, focal uptake on the Tc-99m study and no correlating lesion on the Tl-201 study is more consistent with a well-differentiated tumor and, hence, a more favorable outcome.
Clin Nucl Med. 1995 Aug;20(8):733-4.
Ann Nucl Med. 2000 Aug;14(4):293-8.
No comments posted.
Case Number: 96418Owner(s): Asif Moinuddin and Barry Siegel, Prof of RadiologyLast Updated: 12-15-2010 The reader is fully responsible for confirming the accuracy of this content.
The reader is fully responsible for confirming the accuracy of this content.