Clinical History

The patient is a 44-year-old male with known malignant pheochromocytoma. He has undergone several operative procedures, the most recent one being approximately 6 weeks ago at which time a major debulking operation was performed of the retroperitoneal tumor. The pathologist's at this time are classifying the tumor as a malignant paraganglioma. The patient has received three previous treatments with therapeutic doses of I-131 MIBG. He is seen on an outpatient basis today to determine if there is residual malignant paraganglioma or pheochromocytoma remaining.

Technique

On 08/14/96, the patient received a 1 millicurie injection of I-131 MIBG via an antecubital vein. Twenty-four hours later, anterior and posterior images of the head, neck, thorax, abdomen, and pelvis were obtained. Prior to injection, the patient's thyroid had been blocked the thyroblock tablets. Comparison is made with previous whole body MIBG scans.

Findings

There is now a marked increase in abdominal uptake seen in the paravertebral areas especially on the left. This is the site of previous known residual tumor which is invading the left psoas muscle. A distant metastasis is noted in the left clavicular area. This is a new finding. Additional irregular foci of increased activity is identified in the liver. These foci have occurred in the interval since the last examination, and probably represent metastatic neuroendocrine tumor. In the posterior aspect of the dome of the liver is the utmost prominent probable metastasis.

Impressions

In this case, a therapeutic dose of I-131 MIBG was administered on an inpatient basis. After informed consent, the patient was admitted to the hospital and administered 324 millicuries of I-131 MIBG during a slow infusion of approximately 90 minutes. The patient's blood pressure and heart rate were stable throughout the procedure. The patient tolerated the procedure well. The patient will remain in the hospital until the activity of the patient reaches 30 millicuries.

Comments

None.