Clinical History
The patient is a 47 year-old male with colorectal carcinoma first diagnosed in 12/98. His CT scans were thought to be normal in April of 1999 and in the July of 1999. In August of 1999 and FDG PET scan revealed obvious colon cancer with metastases. He has since undergone surgery and chemotherapy and he returns for re-evaluation. It is of interest that his CEA tumor markers have not been particularly elevated in 12/98 CEA was 1.9, 8/99 2.6, and 12/22/99 3.7. The previous CT scan reports have been evaluated, the images and report of the previous PET scan of 8/6/99 has been reviewed with this study.
Technique
The patient received intravenous injection of 10 mCi of F18 FDG and approximately an hour later whole body imaging
was carried out from shoulders to below the bladder. Comparison is made with a previous PET scan of 8/6/99.
Findings
Today's PET scan demonstrates remarkable improvement from the previous scan of 8/6/99. The main bulk of the tumor and
major metastases are no longer evident. There is no evidence of metastases in lungs or mediastinum. The heart has
concentrated an unusually large amount of FDG, but this is within normal limits. No definite metastases are noted in the
liver. In the left mid abdomen there is a small region of focal uptake which is confluent with the descending colon at the intersection of C56, T93, S83. This is at the most left lateral extent of the previously noted colon cancer as seen on the previous PET study. The activity is much reduced from what was noted previously, but this reducrion could be related to relatively successful chemotherapy. This focus and its position quite superficially may actually be in the abdominal wall. A healing drain site might have this appearance. More superiorly in the left abdomen at the intersection of C66, T71, S88 roughly in the location where one would expect a normal splenic flexure to be, there is another small focus of activity located
quite superficially and also quite laterally. Multiple contiguous sagittal slices about sagittal 88 suggest that this focus is in
bowel. A third site occurred at the intersection of coronal 66, transaxial 83, and sagittal 47. This is also in bowel as there is some linear extent to the focus. These three areas just mentioned may represent either healing or inflammation and do not
necessarily indicate recurrence of colon cancer. The normal bowel often can accumulate FDG to varying degrees as would
healing drainage tracts following the previous recent surgery.
Impressions
MARKED IMPROVEMENT SINCE THE PREVIOUS PET SCAN OF AUGUST 6, 1999. THE PREVIOUSLY MENTIONED SITE IN TODAY'S STUDY MAY INDICATE HEALING OR SOME DEGREE OF INFLAMMATION. RECURRENCE OF COLON CANCER CANNOT BE COMPLETELY EXCLUDED, BUT THE INTENSITY OF THESE THREE REGIONS ON TODAY'S STUDY IS MUCH LESS THAN WHAT WAS SEEN PREVIOUSLY.
Click on the button below to view the CT Scans related to this Colorectal case
