Pancreas and Biliary Tract

The pancreas is a glandular organ that is located in the upper abdominal cavity, behind the stomach (Figure). It produces several hormones (endocrine function), insulin being the most important, as well as enzymes (exocrine function) that play crucial role in the digestion and absorption of nutrients.

Figure

Adenocarcinoma represents nearly the 90% of pancreatic neoplasms. These tumors arise from the exocrine pancreas i.e. the part that produces the digestive enzymes. Although surgical resection is the cornerstone of their management, referral should be based on both tumor stage and patients’ performance status.

The remaining 10% of pancreatic neoplasms consist of various cystic neoplasms (SCN-serous cystic neoplasm, MCN- mucinous cystic neoplasm, IPMN- intraductal papillary mucinous neoplasm, SPN- solid pseudopapillary neoplasms), neuroendocrine tumors (NETs), arising from the endocrine pancreas and other rare neoplasms such as lymphomas or metastatic lesions. In general, cystic neoplasms and neuroendocrine tumors have better prognosis compared to adenocarcinoma.

The appropriate management strategy of pancreatic neoplasms requires excellent knowledge of the area and the available diagnostic tools. Interventional endoscopic techniques including endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) play a crucial role for the correct diagnosis and staging.

What are the risk factors for pancreatic adenocarcinoma?

These include smoking, obesity, male sex, diabetes mellitus and chronic pancreatitis.

What are the symptoms of pancreatic adenocarcinoma?

Symptoms include pain in the upper belly sometimes radiating to the back, jaundice, new onset of diabetes or poor control of pre-existing diabetes, body weight loss, loss of appetite and depression. Given that plenty of digestive diseases may present with similar symptoms, differentiating these from pancreatic cancer may be challenging.

How is pancreatic adenocarcinoma diagnosed?

The most important step is the correct characterization of a pancreatic neoplasm, since it determines both prognostic and therapeutic factors. Imaging modalities such as computed tomography (CT) and magnetic tomography (MRI / MRCP) are of importance. Endoscopic ultrasound (EUS) may enable detailed visualization of a mass as well as tissue collection by means of a needle (FNA). Thus, the histologic type of the neoplasm may be identified, guiding further management on an individualized basis (Figure).

Figure

What is the treatment of pancreatic neoplasms?

According to current guidelines, many cases of pancreatic adenocarcinomas are initially treated with chemotherapy, while surgery may be undertaken later. It should be noted that the best treatment plan should be decided by a specialized multidisciplinary team including gastroenterologists, medical oncologists, radiologists and surgeons.

On the other hand, pancreatic neoplasms with very low malignant potential (e.g. some types of cystic pancreatic neoplasms) may only be followed-up periodically (see under Pancreatic Cysts).

What are pancreatic cysts?

Pancreatic cysts are fluid-filled structures within the pancreas. They are usually incidental findings found during a radiologic examination (ultrasound, computed/magnetic tomography). In rare cases these cysts may cause episodes of pain (mild pancreatitis).

What types of cysts may be found in the pancreas?

Pancreatic cysts are broadly divided in non-neoplastic (e.g. pseudocysts, Figure 1) and neoplastic (cystic neoplasms, Figure 2). The latter comprise the majority of pancreatic cysts. The fluid within the cyst may be either watery (serous) or highly viscous (mucinous). Precise classification of the cyst is mandatory for its further management.

Figure 1
Figure 2

May these cysts evolve into cancer?

Cysts that contain mucus are potentially dangerous since they may evolve into cancer over many years. The size of the cyst plays also a very important prognostic role.

How can we accurately classify a pancreatic cyst?

Your doctor will ask you to undergo some tests including a computed tomography and/or a magnetic tomography. Endoscopic ultrasound (EUS) plays a crucial role in the correct characterization of a cyst and it also enables cystic fluid aspiration for further testing (Figures 2-4). This can be performed by a gastroenterologist who is expert in this area.

Figure 3
Figure 4

How are pancreatic cysts treated?

As already mentioned, the first step is their correct classification. In the case of cysts with negligible risk for malignancy, periodic follow-up is usually enough, as long as they do not produce any symptoms. In symptomatic cysts as well as those with malignant potential surgery may be recommended.

What is acute pancreatitis (AP)?

AP refers to acute inflammation of the pancreas. Most people have mild symptoms and get over pancreatitis without any long-lasting effects. But a few people may get very ill.

What causes AP?

The most common causes are gallstones and alcohol abuse.

  • Gallstones: Gallstones form inside the gallbladder. Both the pancreas and the gallbladder drain into a single tube. If that tube gets obstructed by a gallstone, neither of the organs can drain and that can cause pain. In most cases, obstruction is temporary. Sometimes the stone may get impacted into a region of the intestine called ampulla of Vater. In that case an endoscopic intervention in needed in order to remove the stone (see ERCP).
  • Alcohol: We do not know exactly how alcohol causes AP, but it is evident that even a small amount may trigger the symptoms.
  • Less common causes of AP include viruses, drugs, high calcium or triglceride blood levels.
  • Autoimmune pancreatitis
  • Post- ERCP pancreatitis (see ERCP)

What are the symptoms of acute pancreatitis?

Symptoms of AP include pain in the upper belly which is constant and intense and may radiate to the back, accompanied by nausea/vomiting, bloating and malaise.

How is AP diagnosed?

The basis for AP diagnosis is the patient’s history and physical examination. Several blood tests and radiologic tests (ultrasound, computed or magnetic tomography) may help.

How is AP treated?

AP is treated in the hospital with supportive measures and avoidance of further irritation of the pancreas. Treatment includes:

  • Avoidance of giving food and fluids by mouth,
  • Intravenous hydration,
  • Strong pain medication

It is very important that the patient stops drinking alcohol after an episode of AP, no matter what caused it. In the case of gallstone pancreatitis, removal of the gallbladder (cholecystectomy) is strongly recommended even during the same hospitalization, since it has been shown that delayed surgery increases the risk for AP recurrence.

What is chronic pancreatitis (CP)?

Chronic pancreatitis refers to the condition where the pancreas becomes damaged by long-standing inflammation. Inflammation interrupts normal pancreatic function and the organ becomes gradually scarred down.

What are the causes of chronic pancreatitis?

The most important factor is long-standing alcohol abuse. Smoking produces additive damage. CP develops more commonly in men and the mean age at diagnosis is 50 years.

What are the symptoms of chronic pancreatitis?

The cardinal symptom is middle-upper abdomen pain which may also radiate to the back. The pain usually comes and goes and gets worse after a meal.   Progressively, the pancreas loses its two functions: exocrine and endocrine. Exocrine pancreatic insufficiency presents with diarrhea, weight loss and vitamin/nutritional deficiencies. Endocrine insufficiency leads to diabetes due to decreased insulin secretion.

How is chronic pancreatitis diagnosed?

Chronic pancreatitis causes symptoms only after a major part of the pancreas has been damaged. If the history is suggestive, the diagnosis is made by imaging the pancreas with CT or endoscopic ultrasound (EUS, Figure).

Figure

How is chronic pancreatitis treated?

Alcohol and smoking discontinuation are the cornerstone of chronic pancreatitis management.

Analgesics, insulin and digestive enzymes are also prescribed for pain, diabetes and malabsorption control, respectively.

Careful follow-up by a specialized gastroenterologist is of great importance, given that CP is a risk factor for pancreatic cancer development.

What are gallstones?

Gallstones are stones in the gallbladder – this condition is also called cholelithiasis. The gallbladder is a sac located below the liver which stores bile, a fluid produced by the liver to help in the digestion of fatty foods. After a high-fat meal the gallbladder contracts and empties its contents through a small duct (the common bile duct) into the small intestine.

What are gallstones and what causes their formation?

Gallstones are crystalline bodies that are developed when bile becomes oversaturated. Risk factors for gallstone formation include:

  • Positive family history
  • Female sex
  • History of multiple pregnancies or of a recent pregnancy, use of oral contraceptives (all associated with increased estrogen levels) 
  • Obesity and a history of rapid weight loss.

What are the symptoms?

10-20% of the population have gallstones but 80% of those never  have any symptoms. When gallstones move and occlude the cystic duct they cause biliary colic (pain in the upper belly and/or under the right rib cage) 1-2 hours after meal. If the occlusion continues, the pain becomes constant and is accompanied by nausea, vomiting or even fever, a condition called acute cholecystitis. Rarely, acute cholangitis (fever with tremor, pain and jaundice) or acute pancreatitis may develop.

How are gallstones diagnosed?

In most cases they are found on an abdominal ultrasound. Often, they may be an incidental finding during an ultrasound performed for another reason (asymptomatic gallstones).

How are they treated?

As mentioned, only 20% of patients with gallstones have symptoms. Therefore, removal of the gallbladder (cholecystectomy) is indicated only when gallstones produce symptoms (biliary colic or acute cholecystitis). Otherwise, many unnecessary operations would be performed, with their attendant complications.

Currently, cholecystectomy is performed laparoscopically, i.e. with small incisions in the abdomen. This has less postoperative pain and shorert hospital stays.

If the stone has moved into the common bile duct, its removal is achieved by means of ERCP (see ERCP) and then the gallbladder is removed laparoscopically.

Figure

What are gallbladder polyps?

They are protrusions of the lining of the gallbladder. 95% of them are hyperplastic or represent lipid depositions (cholesterol), while the remaining 5% are adenomatous.

Do they cause symptoms?

Usually, gallbladder polyps do not cause any symptoms. Very rarely, they may be associated with pain of the gallbladder.

How are gallbladder polyps diagnosed?

In the vast majority of cases they are found incidentally during upper abdominal ultrasound performed for another reason.

How are gallbladder polyps treated?

Only polyps that produce symptoms or are sized more than 1 cm have an indication for treatment. In these cases, cholecystectomy is performed. Other cases do not necessitate surgical management. However, periodic follow-up is sometimes suggested.