NMS. Casos Clínicos

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Chapter 7 ♦ Pancreatic and Hepatic Disorders

Figure 7-16: EUS showing a mass in the pancreas. Arrow is pointing to the obstruction of the splenic vein by the tumor.

cancer can be associated with adjacent pancreatic areas with chronic scarring due to a local inflammatory process, making the biopsy look similar to chronic pancreatitis and mislead- ing the surgeon into thinking the process is benign. Most experienced pancreatic surgeons are comfortable proceeding with pancreatic exploration without a preoperative pathologic diagnosis. Surgeons prefer to biopsy the lesion and have a definitive diagnosis prior to surgery, but a biopsy-proven diagnosis is not always possible. It is important to try and have or establish a tissue diagnosis at surgery but prior to pancreatic resection because the operation is extensive, and the risk of significant complications is high. Final evaluation using an endoscopic transduodenal biopsy reveals a definitive diagnosis of pancreatic adenocarcinoma involving the head of the pancreas. Q: What preoperative findings would make the patient inoperable? A: To tolerate this procedure, the patient must have an acceptable general medical condition, with no evidence of distant metastasis . Further evaluation is necessary if any of these condi- tions is present. The CT scan and EUS require careful evaluation to check for evidence of local invasion of the portal vein, or superior mesenteric vessels, nearby structures, or local lymph nodes (Figs. 7-17 and 7-18). The liver must be free of metastatic lesions . The use of laparos- copy assists in staging the patient. This allows direct visualization of some of these structures and confirms any metastases by biopsy. Confirmed metastases are a sign of incurable disease. In essence, the best chance for resectability is a small lesion that is limited to the pancreas. There are no obvious metastases on CT scan or EUS, and you determine that the patient is operable. Q: What operative decisions are necessary? A: It is often difficult to determine the resectability of pancreatic cancer preoperatively. Local invasion of visceral vessels may not always be apparent on CT or EUS. A CT scan may miss liver lesions smaller than 1–2 cm and peritoneal and omental metastases. Therefore, the first phase of surgery involves assessing for distant metastasis by examining the liver and peritoneal surfaces, with biopsy of suspicious lesions for frozen section diagnosis. Lymph node metastases in the periaortic or celiac region indicate the tumor is beyond the limits of resection and should be confirmed with biopsy. SAMPLE