The diagnosis based on the preceding history, physical examination, laboratory data, endoscopy, imaging studies and pathology is: Adenocarcinoma of the pancreatic head

Consider the following questions about the management of this patient's problems before proceding:

1. Did endoscopic ultrasound add any information in this patient's preoperative evaluation considering that he already had a CT scan showing a mass with no major vessel involvement?
 

2. How sensitive and specific is EUS in assessing vessel involvement by tumor in pancreatic adenocarcinoma?
 

3. What are the newer modalities available to stage pancreatic adenocarcinoma and where does EUS fit in?

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