FORT LAUDERDALE, Fla--Clinicians now have at their disposal more accurate staging technologies for pancreatic cancer than were available in the past.
FORT LAUDERDALE, Fla--Clinicians now have at their disposal more accuratestaging technologies for pancreatic cancer than were available in the past.
The appropriate roles of these technologies, particularly endoscopicultrasound (EUS) and laparoscopy, engendered the most controversy amongthe panel members charged with creating preliminary practice guidelineson pancreatic cancer for the National Comprehensive Cancer Network (NCCN),panel chair Margaret Tempero, MD, said in an interview.
The various staging modalities provide different types of informationand also differ with regard to cost and invas-iveness, said Dr. Tempero,of the University of Nebraska Medical Center. She presented the pancreaticcancer guidelines at the NCCN's second annual conference.
Consequently, she anticipates that the panel's recommendations aboutthe use of staging technologies in various situations will change as theguidelines undergo review by the NCCN institutions.
The pancreatic cancer practice guidelines, developed by a nine-membermultidisciplinary panel , consist of seven distinct paths for the workupand treatment of patients with ductal adenocarcinoma. The decision of whichpath should be followed for a particular patient rests primarily on theresectability status of the cancer and whether there is evidence of metastaticdisease. Both of these determinations hinge on accurate staging.
Margaret Tempero, MD
Panel Chairman, University of Nebraska Medical Center
Al Benson, MD
John L. Cameron, MD
The Johns Hopkins Oncology Center
Ephraim S. Casper, MD
Memorial Sloan-Kettering Cancer Center
John Hoffman, MD
Fox Chase Cancer Center
Ted Lawrence, MD
University of Michigan Cancer Center
Ted Martin, MD
Arthur G. James Cancer Hospital &
Research Institute at Ohio State University
Cornelius McGinn, MD
University of Michigan Cancer Center
Christopher Willett, MD
Massachusetts General Hospital
Since definitions of resectability and unresectability are not clearin the literature, the panel developed its own criteria, and although theseare fairly noncon-troversial, the yardsticks for borderline resectabilitymay provoke some debate, Dr. Tempero said.
The panel deems lesions in either the head or body of the pancreas borderlineresectable when there is bilateral or severe unilateral superior mesentericvein or portal impingement, tumor abutment on the superior mesenteric artery,gastroduodenal artery encasement up to the origin at the hepatic artery,or direct invasion into the transverse colon.
For lesions in the tail of the pancreas, extension into the adrenalgland, kidney, or colon is characterized as borderline resectable.
Which Staging Tests to Use When?
The crux of the controversy over staging technologies is which testor tests to use when, Dr. Tempero said.
To determine resectability in the patient who presents with a mass inthe head of the pancreas and who is not jaundiced, the panel recommendsspiral (helical) CT. If the scan indicates that the mass is potentiallyresectable, the patient should undergo a laparotomy, and, if that confirmsthe CT findings, the resection should be completed.
The guidelines do not require a preop-erative biopsy prior to laparotomy."Because of one of the histologic hallmarks of pancreatic cancer,ie, associated desmo-plasia, preoperative biopsies can often be misleading,"Dr. Tempero noted. Thus, if a biopsy is taken in a desmoplastic area ofthe pancreas in a patient who actually has an adenocarcinoma, the cancermay go undetected.
If findings on spiral CT indicate that a mass is borderline resectable,the panel recommends the use of endoscopic ultrasound (EUS) (coupled witha transgas-tric biopsy) to ascertain whether that mass is truly resectable.
A number of studies have suggested that EUS is a far better stagingtool than conventional ultrasound or CT, Dr. Tempero said. "However,we recognize that EUS is an operator-dependent modality. And even withinour own NCCN institutions, we have not yet determined that all institutionshave dedicated personnel who are skilled in this procedure."
If EUS findings indicate that the borderline lesion is, indeed, resectable,the committee advocates the use of laparos-copy rather than laparotomyto determine whether metastases are present.
"The reason for this is that many of these patients with borderlinelesions will have peritoneal studding or other evidence of metastatic diseasethat would not have been apparent on the CT scan," Dr. Tempero said."And so, it was the panel's feeling that, by doing a preop-erativelaparoscopy, you would be able to spare some of these patients from undergoinglaparotomy."