Clinical

PET scan facilitates decision-making for colorectal metastases in liver

Last Updated: 2007-01-10 9:00:16 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Preoperative PET scanning improves the selection process for patients being considered for hepatic resection of colorectal metastases, according to a report in the December 2006 Archives of Surgery.

PET is emerging as a complementary imaging modality to detect metastases not identified by conventional diagnostic modalities such as MRI and CT, the authors explain.

Dr. David L. Joyce and colleagues from The Johns Hopkins Medical Institutions, Baltimore, Maryland evaluated the impact of incorporating PET or PET-CT with other imaging modalities on the clinical management decisions in 71 patients being considered for surgery for colorectal liver metastases.

Thirty of 229 lesions identified using all types of imaging were seen with conventional diagnostic imaging but not PET, the researchers report, and 46 were seen on PET but not conventional diagnostic imaging. One hundred fifty-three (67%) of the lesions were seen with both.

Of the 23 patients in whom PET studies detected additional disease, most had extra-abdominal findings (57%), the researchers note. Ten patients had intra-abdominal findings, including four with intrahepatic disease, five with extrahepatic disease, and one with both.

PET findings significantly changed the clinical management in 17 patients (24% overall), the investigators say, but no patients was denied resection on the basis of false-positive PET findings.

"These data suggest that PET is useful in confirming lesions that are suspected of being metastases on conventional diagnostic modality findings," the authors conclude. "Furthermore, PET can detect additional sites of metastatic disease that are missed on conventional diagnostic modality findings."

"These advantages have direct implications for patient management, in that they can improve patient selection and limit the number of unnecessary surgical explorations in this setting," the researchers suggest.

Based on these findings, they recommend routine evaluation by PET, when available, of patients with potentially respectable hepatic metastases from colorectal cancer.

Arch Surg 2006;141:1220-1226.