Source: DGNews  |  Posted 3 years ago

By Roberta Friedman, PhD

SAN FRANCISCO -- October 20, 2008 -- Laparotomy is the best way to stage neuroendocrine cancers, as imaging misses many of the metastases, researchers reported here at the American College of Surgeons (ACS) 94th Annual Clinical Congress.

Anthony J. Chambers, MS, Department of Surgery, University of Calgary/Tom Baker Cancer Centre, Calgary, Alberta, presented findings from a retrospective comparison of preoperative imaging findings and surgical findings in 60 patients with midgut neuroendocrine tumours.

Of this cohort, 57 patients had preoperative imaging with a combination of computed tomography (CT), 25 had magnetic resonance imaging (MRI), and 48 had radionuclide studies.

Results showed that imaging and other screening measures (radionucleotide studies or biochemical markers, such as 5HIAA) identified 3 patients as having peritoneal metastases, but laparotomy revealed these metastases in 15 patients.

Preoperative screening indicated mesenteric lymph node metastases in 45 patients, while laparotomy found 53 patients had this spread. Hepatic metastases were found preoperatively in 39 patients, but 45 patients were found to have these tumours on laparotomy.

Carcinoid syndrome was identified in 5 patients. Imaging failed to detect hepatic metastases in 6 cases and underestimated the extent of hepatic spread of the cancer in 15 cases.

"Imaging underestimates hepatic metastatic disease by 33%," Dr. Chambers said in his presentation on October 16. "Hepatic metastases should be suspected in patients with carcinoid syndrome."

Neuroendocrine cancer is rare and indolent, but is treatable with surgery or chemotherapy, said Mark Sawicki, MD, University of California, Los Angeles, Los Angeles, California, who commented on the paper at the session.

"If we are missing 13% of hepatic metastases, we can't measure the response to therapy," Dr. Sawicki said.

[Presentation title: The Role of Imaging Studies in the Staging of Midgut Neuroendocrine Tumors.]