NMS. Casos Clínicos

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Part II ♦ Specific Disorders

Q: What is the next management step? A: If distal common duct obstruction is present but nomass is seen on ultrasound, contrast-en- hanced CT of the abdomen is appropriate. CT is better than ultrasound at visualizing the distal common duct area. It may be possible to visualize the mass further with finer CT cuts of the pancreas (Fig. 7-14), but often, the pathology can still not be elucidated. If a mass can be visualized, ERCP may further define the lesion and allow the gathering of brushings for cytology. Transcutaneous abdominal ultrasound is not the best method for visualizing the distal bile duct and pancreatic head area because intestinal gas obscures the view. Q: What is the next management step? A: In this setting, upper gastrointestinal (GI) endoscopy and endoscopic ultrasound (EUS) per- formed through the duodenal wall commonly allow an excellent assessment of the pancreatic head. It is possible to combine ERCP with EUS if further information is necessary. CT and EUS also both allow assessment of the tumor to discover whether local metastasis, positive lymph nodes, portal vein involvement, or liver metastases are present (Fig. 7-15) . You perform a CT scan of the abdomen and see no mass in the pancreas.

An EUS allows you to visualize a 2-cm mass in the head of the pancreas (Fig. 7-16).

Q: Is biopsy of the mass appropriate? A: Establishing a tissue diagnosis is particularly difficult in patients with chronic pancreati- tis , where a thickened, scarred pancreatic head can feel like cancer. In contrast, pancreatic

Figure 7-14: CT scan showing a mass ( arrow ) in the head of the pancreas. Figure 7-15: ERCP showing a narrowing of the distal common bile duct and a “double duct” sign, which is a dilated common bile duct and pancreatic duct. SAMPLE