Full CH 1 _Lillemoe-9781496385574

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PART I Pancreas and Biliary Tract

regarding its relationship to surrounding structures. Pancreatic adenocarcinoma usually appears as a hypoattenuating lesion when the pancreatic parenchyma is maximally enhanced in the early arte- rial phase. CT has very high sensitivity, approaching 100%, for lesions ≥ 2 cm in size. There does, however, appear to be a significant decrease for smaller tumors, with sensitivities ranging from 67% to 77%. CT is nevertheless an indispensable tool for determining resectability, as sensitivity for vascular involvement can exceed 90%. Despite continuing advances in CT technology, one draw- back remains the lack of accuracy in identifying small liver metastases, small peritoneal nodules, or low-volume carcinomatosis. This can be a significant issue and can lead to a false-negative result in ~10% of cases. Endoscopic Ultrasound The role of endoscopic ultrasound (EUS) in the preoperative planning for pancreaticobiliary surgery is somewhat controversial. Like CT, EUS can provide information regarding the relationship of lesions to major vascular structures, but multidetector CT scanning is of such high quality that EUS is generally not necessary to accomplish this. Based on one study, sensitivity for EUS in detecting vascular invasion is 86%, whereas specificity is only 71%, although the quality of EUS is opera- tor-dependent. EUS does, however, provide an excellent avenue for obtaining a tissue diagnosis which is becoming increasingly required in many institutions given the important trend toward neo- adjuvant therapy even for resectable disease, in addition to borderline disease. This may be most nec- essary in patients with ambiguous lesions but is also particularly important in patients—resectable, borderline resectable, or unresectable—who will require chemotherapy or chemoradiotherapy as the first treatment modality. In addition, EUS may be the procedure of choice for identifying high-risk stigmata or worrisome features in patients with intraductal papillary mucinous neoplasms. Finally, EUS may be useful on occasion for identifying patients with metastatic disease, such as to the celiac lymph nodes or to EUS-accessible liver lesions, and this information may help guide management. Magnetic Resonance Imaging Magnetic resonance imaging (MRI) has a role in imaging the pancreatic duct and cystic lesions of the pancreas, but the choice of MRI versus CT as the primary imaging modality is largely institu- tion-dependent. The authors’ institutions favor CT, at least initially, but recognize that MRI can be useful in identifying pancreatic anatomy and pathology. With increasing recognition of intraductal papillary mucinous neoplasms, MRI has become more frequently used as a surveillance tool in many institutions, including ours. Valuable information about the pancreatic duct can be noninva- sively elucidated using magnetic resonance cholangiopancreatography. This is particularly import- ant when assessing a distal bile duct stricture or when planning a pancreatic drainage procedure in the setting of chronic pancreatitis. Positron Emission Tomography There is currently insufficient evidence to advocate for the regular use of positron emission tomog- raphy scanning in the diagnosis and staging of pancreaticobiliary disease. As with CT scan, the sensitivity of positron emission tomography is closely associated with the size of the lesion, making it susceptible to missing low-volume metastatic disease. Patient Preparation The risk that a major operation poses to the patient is a function of several factors, including med- ical comorbidities, surgeon experience, and institutional capability. Multiple studies have shown improved outcomes with higher institution and surgeon volume, and with use of a well-designed program for Enhanced Recovery after Surgery (ERAS).

Medical Considerations The goal of the preoperative medical evaluation is not merely to secure so-called “medical clear- ance” or “cardiac clearance” but rather to optimize the patient’s health and to stratify and minimize risk. The predominant nonsurgical contributor to postoperative morbidity and mortality is the car- diovascular system, and given that perioperative myocardial infarction has been associated with a mortality rate as high as 70%, preoperative cardiac evaluation is essential. The elective, nonemer- gent nature of most pancreaticobiliary procedures allows, and indeed demands, preoperative medi- cal optimization, especially when the use of neoadjuvant therapy is becoming more commonplace. Copyright © 2019 Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited.