Endoscopic Ultrasonography (EUS) Vs Helical CT for the locorregional staging of pancreatic cancer: prospective comparative trial using histology of surgery piece as the gold standard

Accuracy of helical CT for locorregional staging and resectability of pancreatic cancer is limited. Development of EUS, with a higher resolution for the evaluation of pancreatic diseases, has led to an advance in this important issue in the management of the disease. However, there are very few comparative trials between CT and EUS, using histology as the gold standard. Therefore, we aimed at evaluating the accuracy of EUS at the local staging (T) and lymphatic extension (N) in pancreatic cancer, in comparison with contrast-enhanced helical CT scan, using histology of surgery piece as the gold standard. Methods: 30 consecutive patients (mean age 62 years; range 41–85, 17 male, 13 female) who were operated upon for pancreatic cancer were prospectively included. The preoperative EUS was performed under conscious sedation by the lineal scanning Pentax FG-38UX echoendoscope, by two operators who were blinded for the result of helical CT scan. The intraoperatory and histology findings were used as the gold standard. We evaluated the stage T and N using the TNM classification (AJCC-2002). Data analysis was made using the chi-cuadrado test. Results: 14 patients (46.6%) were classified as T4 stage, and 16 (53.3%) as T3. None of them were T2 or T1. According to N stage, 21 patients (70%) were at N1 stage, and only 9 (30%) were N0. Helical CT made a correct staging TN only in 8 patients (26.6%), compared to 24 patients (80%) correctly evaluated by EUS (p<0.01). T staging was well-made by helical CT in 46.6%, compared to 86.6% by EUS (p<0.05). About T staging, 16 patients (53.3%) were under-staged by the helical CT, and about N staging, 14 patients classified by CT as N0, were N1. With EUS only six patients were wrongly staged (one T4N1 as T3N1, and two T3N1, one as T3N0 and other as T2N0, and two T3N0 as T3N1 and a T4N0 as T2N0). Conclusions: EUS shows a higher accuracy than helical CT for locoregional staging of pancreatic cancer. Routine application of EUS in pancreatic cancer staging will reduce unnecessary surgery in patients wrong classified as resectable.