Oct. 3, 2003 -- Very high levels of CA19-9 may indicate unresectable pancreatic cancer despite the appearance on imaging, according to the results of a study published in the September issue of the Archives of Surgery. Confirmatory laparoscopy or other additional staging modalities are suggested to avoid unnecessary laparotomy in these patients.
"Despite advances in preoperative radiologic imaging, a significant fraction of potentially resectable pancreatic cancers are found to be unresectable at laparotomy," write Michael G. Schlieman, MD, from the University of California-Davis Cancer Center in Sacramento, California, and colleagues. "Current staging with the use of bolus-contrast, triple-phase helical computed tomography (CT) is only 75% to 80% accurate at determining resectability, and further radiologic and endoscopic staging procedures have not significantly improved the accuracy."
From March 1, 1996, to July 31, 2002, 125 patients at an academic tertiary care referral center underwent surgical exploration for potentially resectable pancreatic cancer based on a preoperative CT scan, including 89 who had preoperative measurement of tumor markers CA19-9 and carcinoembryonic antigen.
Of the 89 patients, 40 (45%) underwent resection for localized disease, 25 (28%) had locally advanced unresectable disease, and 24 (27%) had metastatic disease. The mean level of CA19-9 adjusted for the degree of hyperbilirubinemia was 63 U/mL in those with localized disease, 592 U/mL in those with locally advanced disease ( P = .003), and 1,387 U/mL in those with metastatic disease ( P < .001 vs. localized disease).
Using a threshold-adjusted CA19-9 level of 150, the positive predictive value for determination of unresectable disease was 88%. Carcinoembryonic antigen level was not correlated with extent of disease.
Among the 33 patients with preoperative adjusted CA19-9 levels greater than 150, preoperative diagnostic laparoscopy could have identified peritoneal or hepatic metastases in 14 of the 16 patients found to have metastatic disease at laparotomy. Preoperative stratification using CA19-9 levels could therefore improve the yield of staging laparoscopy to as high as 42%, preventing unnecessary laparotomy in nearly half of the patients.
"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," the authors write. "These patients may benefit from additional staging modalities such as diagnostic laparoscopy to avoid unnecessary laparotomy."
Arch Surg. 2003;138:951-956
Reviewed by Gary D. Vogin, MD
Medscape Medical News © 2003 Medscape
Cite this: Laurie Barclay. Very High CA19-9 Levels Suggest Unresectable Pancreatic Cancer - Medscape - Oct 03, 2003.