A significant proportion of potentially resectable pancreatic cancers are found to be unresectable at laparotomy.
In this study, researchers from California evaluated whether serum levels of CA19-9 (cancer antigen) and carcinoembryonic antigen can identify patients with unresectable pancreatic cancer.
They identified 125 patients who underwent exploration for potentially resectable pancreatic cancer based on a computed tomographic scan, between 1996 and 2002. In 89 of these patients a preoperative tumor marker had also been measured.
The physicians correlated preoperative tumor markers with the extent of disease at exploration. As CA19-9 is excreted in the biliary system, the team adjusted CA19-9 for the degree of hyperbilirubinemia.
The team found that, of the 89 patients, 45% had localized disease and underwent resection. A further 28% had locally advanced unresectable disease, and 27% had metastatic disease.
They determined that the mean adjusted CA19-9 level was significantly lower in patients with localized disease, compared to those with locally advanced or metastatic disease.
|The positive predictive value for determination of unresectable disease was 88%.|
|Archives of Surgery|
Using a threshold adjusted CA19-9 level of 150, the team found that the positive predictive value for determination of unresectable disease was 88%.
Carcinoembryonic antigen level was not correlated with extent of disease.
Dr Michael Schlieman's team concluded, "Among the patients with resectable pancreatic cancer based on preoperative imaging studies, those with abnormally high serum levels of CA19-9 may have unresectable disease".
"These patients may benefit from additional staging modalities such as diagnostic laparoscopy to avoid unnecessary laparotomy".