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and calcifications, especially in advanced disease. Compared to other imaging modalities, MRCP gives the most detailed visual of pancreatic ductal anatomy, such as filling defects, main and side branch duct dilations, and irregularity of the main pancreatic duct. Administration of IV secretin during MRCP can provide data on duct compliance and even pancreatic flow, which may be helpful surrogates for pancreatic exocrine function, thus enhancing the sensitivity of detecting early chronic pancreatitis.²⁰

      Endoscopic ultrasound (EUS) is another diagnostic modality that has gained support in diagnosing early chronic pancreatitis. It also evaluates parenchymal and ductal changes, utilizing a variety of EUS imaging criteria. However, there is a lack of standardization regarding EUS scoring tools for chronic pancreatitis, along with significant inter‐operator interpretation variance.

      When chronic pancreatitis is suspected, our preference is to use CT or MRCP as the first‐line imaging modality, depending on local preference and experience.

      Complications of chronic pancreatitis

      A primary complication of chronic pancreatitis is pain, the management of which will be discussed below. Nutritional issues, in particular fat malabsorption, can be seen in severe chronic pancreatitis and may lead to obvious steatorrhea and weight loss. Diabetes due to chronic pancreatitis, sometimes termed type 3c diabetes, is relatively uncommon but can be more difficult to control due to both insulin and glucagon insufficiency. Episodes of hyper‐ and hypo‐glycaemia are more likely. They can be further exacerbated by concomitant exocrine insufficiency, resulting in malabsorption. While diabetes is relatively uncommon in chronic pancreatitis, it is a nearly inevitable consequence of major pancreatic resection such as Whipple surgery (see Chapter 86).

      Management of chronic pancreatitis

      Pain is relatively less common in the elderly with chronic pancreatitis, but when it occurs, it impairs the quality of life. Opiate drugs should be avoided because of the risks of narcotic medications in the elderly, including narcotic dependence. Non‐steroidal anti‐inflammatory drugs (NSAIDs), tricyclic antidepressants, and neuromodulators (e.g. gabapentin) are often first‐line therapies.

      If drug therapy fails to control pain, other options, such as deafferentation techniques (e.g. celiac axis block), have been tried with variable success. If imaging shows clinically significant pancreatic duct strictures or large obstructing pancreatic duct stones, ERCP can be an option before surgical techniques are considered. In general, surgery for chronic pancreatitis should be rare, and the best outcomes are generally in the subgroup of patients with a distinct pancreatic ductal stricture causing a ductal obstruction that can be relieved surgically. Surgical pancreatic resections or total pancreatectomy with islet autotransplantation (TPIAT) have gained increasing success in the younger population for the treatment of CP; however, they have not been well studied in the older population.

      Attempts to control steatorrhea by orally administered pancreatic enzymes are worthwhile, and the dose should be titrated to achieve a normal bowel movement frequency. Malabsorption of fat‐soluble vitamins occurs and should be treated with appropriate supplements.

Pancreatic cysts and tumours

      Cystic lesions of the pancreas

      Cystic lesions of the pancreas are very common findings in the era of modern cross‐sectional imaging and are usually discovered incidentally. Recent studies have shown that up to 40% of adults will have a small pancreatic cyst noted incidentally on abdominal MRI scans.²¹

      Broadly speaking, pancreatic cysts can be divided into neoplastic and non‐neoplastic categories. Of the non‐neoplastic cysts, the majority are inflammatory lesions, most commonly pseudocysts, which can be encountered as a sequalae of acute pancreatitis. These inflammatory cysts are variably symptomatic, and depending on their anatomical location and morphology, EUS sampling or drainage may be indicated and should be referred for evaluation by a gastroenterologist. Other non‐neoplastic cysts are fairly rare but include true cysts, retention cysts, mucinous non‐neoplastic cysts, and lymphoepithelial cysts, all of which may be difficult to definitely diagnose and are beyond the scope of this chapter.

      Neoplastic cysts are quite common, and certain categories of pancreatic cystic neoplasms may require surveillance or even consideration of resection because of malignancy risk. The two most common types of pancreatic cystic neoplasms are intraductal papillary mucinous neoplasms (IPMNs), which are precancerous and typically require surveillance, and serous cystadenomas (SCAs), which are typically benign and may not require surveillance. There are several other, less common, pancreatic cystic neoplasms, including mucinous cystic neoplasm (MCN) and pseudopapillary neoplasm, extensive discussion of which is beyond the scope of this chapter.

      As a general rule, any pancreatic cystic lesion greater than 1 cm should, even if incidentally discovered, be referred to a gastroenterologist to help determine appropriate additional testing and/or surveillance modality and interval. If there is uncertainty regarding the nature of a pancreatic cyst <1 cm in size, then interval MRCP imaging (typically at 6–12 months) or referral to a gastroenterologist are both reasonable considerations; however, the clinical significance of a diminutive pancreatic cyst in an elderly patient is questionable, particularly if other chronic health conditions are present.

Table 21.1 Pancreatic endocrine tumours.

Type	Age at diagnosis (years)	Five‐year survival rate (%)	Clinical characteristics
Insulinoma	50–60	90	Fatigue, hypoglycaemia
Gastrinoma	60–70	55	Gastric pain, weight loss
Glucagonoma	50–60	90	Weight loss, diabetes, rash
Somatostatinoma	60–70	30	Diabetes, gallstones, weight loss, steatorrhea
VIPoma	40–60	45	Flushing
Pancreatic peptideomas	40–60	40	None

      Endocrine tumours of the pancreas

Endocrine tumours of the pancreas are rare. These tumours are classified according to the hormone they excrete, which typically correlates with the clinical presentation, although some low‐grade pancreatic neuroendocrine tumours may be found incidentally on imaging without clinical symptoms. Table 21.1 describes the common pancreatic endocrine tumours and their clinical characteristics.²²

      Most pancreatic neuroendocrine tumours have malignant potential and may be part of the multiple endocrine neoplasia syndrome. Suspicion of a pancreatic neuroendocrine tumour, either on clinical grounds or based on imaging findings, should generally prompt referral to a multidisciplinary team including a gastroenterologist and surgeon. Endoscopic‐ultrasound guided biopsy is typically the first step in the diagnostic approach.

      Pancreatic

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