NEW YORK (Reuters Health) – In patients with potentially resectable colorectal liver metastases, the use of combined PET and CT imaging (PET-CT) identifies those with occult extrahepatic disease and who are therefore deemed incurable, according to a UK team

However, within this group, a subset demonstrates a better-than-expected outcome “and as such, might benefit from a more aggressive surgical approach, but with palliative intent?” the investigators suggest.

Dr. Hassan Z. Malik and colleagues at University Hospital Aintree, in Liverpool, evaluated outcomes in 532 patients with colorectal liver metastases seen at their tertiary hepatobiliary unit since the introduction of PET-CT for staging in 2008.

The patients fell into three categories: 80 patients were found to have occult extrahepatic disease detected by PET-CT, which rendered them unresectable, and were therefore offered palliative care; 161 patients were offered palliative care upfront because of extensive multi-site disease seen on initial CT or because of progression during chemotherapy; and 291 underwent surgery with curative intent.

Median overall survival was 10.9 months in the group with extrahepatic disease, 12.0 months among those with multi-site or progressive disease, and 46.7 months for those who underwent surgery.  Corresponding rates of 5-year overall survival in the three groups were 6.5%, 6.1% and 43.0%, the authors report in the European Journal of Surgical Oncology online November 15.

“We have confirmed that PET-CT is effective in selecting patients with occult extrahepatic disease, who have a poor survival outcome as those patients with disease progressions during chemotherapy,” Dr. Malik and colleagues conclude.

When they further analyzed outcomes in the group with extrahepatic metastases, they found that survival varied with the extent of disease. Median overall survival was 15.0 months for those with metastases in only the abdomen or pelvis; 11.0 months among patients with both thoracic and abdominal/pelvic involvement; and 8.1 months for those with non-torso metastases.

The trend toward better survival in the single-compartment versus dual-compartment metastatic groups was not statistically significant, the investigators note.  “Nevertheless,” they conclude, “it does raise a controversial question as to whether there is a role in offering more aggressive surgical intervention to patients in this highly selective single compartment metastatic group.”

SOURCE: FDG-PET-CT is effective in selecting patients with poor long term survivals for colorectal liver metastases

Eur J Surg Oncol 2013