Octreotide Scan

Definition:
An imaging test used to determine areas of abnormal tumor cells of neuroendocrine origin. These tumors constitute a group of unusual cancers that arise, from early development as an embryo, to cells related to the nervous system, but also produces hormones. These tumors are referred to as carcinoid tumors, most of which arise from the gastrointestional tract. Additionally, this agent can also detect another type of tumor arising from the adrenal gland referred to as a pheochromochytoma.

Indications / Risks / Benefits:
This exam is oftentimes used to determine the presence of the primary cancer as well as cancer cells which have spread (“metastatic”) from the primary site.

There are no significant risks associated with the examination.

The benefit is the ability for your doctor to contour your therapy specifically for your situation.

How we do the exam / procedure:
The examination is performed

Imaging camera

Anatomy

Octreotide Scan Images

Pre-test directions:
None.

What to expect during the exam / procedure:
The patient receives an intravenous injection of the slightly radioactive substance and returns to the department four to six hours later for a scan of the total body. Then three more scans follow at 24, 48, and 72 hours after the injection. At 24 and 48 hours in addition to the total body scans, additional scans are obtained (SPECT) where the camera slowly orbits around the patient to gather information for the computer to process three dimentional images. Each total body scan takes approximately 30 minutes, and the SPECT scans take an additional 40 minutes each.

Post care directions:
None.

Exam limitations:
This examination helps locate the primary cancer, for carcinoid is usually in the abdomen, and pheochromocytoma is usually in the abdomen. However, both of these tumors can be in other locations such as the chest or neck, which will be missed with the SPECT is performed over the abdomen as is the usual case. However, the total body scans should alert the nuclear physician of the usual location. Other limitations are small size, or a location next to a metabolically active area which doesn’t contain tumor cells.