Colorectal Cancer Case Study 02


Clinical History
67-year-old female with history of colon cancer who underwent a left hemicolectomy with splenectomy one year previous, presented with a recently biopsied right pericolic soft tissue mass. PET/CT scan was recommended for restaging.

Imaging Findings
NUCLEAR MEDICINE PET/CT
STATED REASON FOR REQUEST: Restaging colorectal cancer
TECHNIQUE: Emission scanning was performed extending from the base of the skull through the pelvis approximately one-hour following radiotracer administration. Images were constructed with and without attenuation correction.
BLOOD GLUCOSE: 99 mg/dL.
COMPARISON: CT portion of PET/CT exam from same date

PET/CT FINDINGS: There were seven focal areas of abnormal intense increased uptake corresponding to soft tissue abnormalities in the abdomen and pelvis. In addition, a cystic area in the right ovary that was seen on the CT portion of the scan, showed a mural nodule which had moderate uptake of radiopharmaceutical on the PET portion. There was no other abnormal uptake identified in the chest or rest of the visualized body.

Diagnosis
Abnormal study with findings consistent with malignancy, suspicious for peritoneal implants in the abdomen and pelvis. In addition, the moderate uptake of radiopharmaceutical identified in a nodular density along the wall of the cystic lesion in the right ovary was slightly suspicious for an additional metastasis from the colon cancer, although primary malignancy could not be excluded.

Treatment
The patient was scheduled for chemotherapy.

Discussion

In this patient with colorectal cancer, small recurrent disease was easily identified and correctly localized utilizing PET/CT. Although PET/CT cannot detect microscopic disease, it is very good for finding small mesenteric implants that might be easily missed on CT alone. This patient was subsequently treated with chemotherapy without even having a biopsy to confirm recurrence because of the rising CEA levels and convincing imaging findings.

Data courtesy of Dr. Todd Blodgett, University of Pittsburgh Medical Center, Pittsburgh, PA, USA

* Any of the protocols presented herein are for informational purposes and are not meant to substitute for clinician judgment in how best to use any medical devices. It is the clinician that makes all diagnostic determinations based upon education, learning and experience.