lesion of pancreas

Lesion of PANCREASR3 Peerawit Songsiri

Table of Contents

Embryology & Anatomy 1

2 Congenital anomalies

3 Pancreatitis

4 Cyst and pseudocyst

5 Functional pancreatic disorder

6 Neoplasm

Embryology & Anatomy

Embryology

• Originate during 4th week of gestation from 2 endodermal buds that arise from caudal part of foregut • Dorsal duct

• Base of pancreatic diverticulum -> minor duct (Santorini) and papilla, body and tail of pancreas

• Ventral duct• Biliary diverticulum -> major duct (Wirsung), head of pancreas

• Fuse at 6-7 wks of gestation, may complete until perinatal period • Ventral bud consist 2 lobules open into hepatic diverticulum close

to gallbladder -> “common bile duct”

Embryology

Anatomy

• Retroperitoneal organ

Right on L2, lies in c loop of duodenum

Body cover L1

Tail rise to T12

Under SMA

Anatomy

Anatomy

Anatomy

2 tissue type

1. Exocrine ( acinar cells, centro-acinar, and ducts)

2. Endocrine cells

Blood supply

Congenital anomalies

• Annular pancreas

• Pancreas divisum

• Ectopic pancreatic rest

• Congenital short pancreas

Aunnular pancreas

Annular pancreas

• Rare condition• Second part of duodenum is surrounded by ring of pancreatic

tissue continuous with the head of the pancreas• Can cause duodenal stenosis or obstructive symptoms in first

days of life• Cause

• Faulty rotation of ventral pancreatic bud

Annular pancreas

Epidemiology

• 1 in 20,000 birth• Male : female = 2 :1 • Possible hereditary link• Associate with intestinal malrotation, trisomy 21

Clinical

• Bilious vomiting• “double-bubble” sign

Management

• Bypass of the obstructing lesion • Duodenoduodenostomy• Gastrojejunostomy

• Resection or division of annular pancreas should not be performed due to the variable and complex ductal system

Pancreas divisum

Pancreas divisum

• 10% of population ( most common congenital anomaly)• Can be found up to 25% in chronic pancreatitis • Result from • Duct of Wirsung is small, duct of Santorini becomes major ductal

system• If the orifice of accessory papilla is stenotic -> pancreatitis

• Majority of exocrine secretion drain to minor duct

Incidence

• Higher in patients with unexplained recurrent pancreatitis • 7.4% of all children with pancreatitis• 19.2% of relapsing or chronic pancreatitis

Investigation

• Magnetic resonance cholangiopancreatography (MRCP)• Noninvasive and accurate method • Fail to visualized duct of Wirsung

after injection of major papilla• Dilatation, irregularity, stricture

Investigation

• Endoscopic retrograde cholangiopancreatography (ERCP)• Most definitive and reliable diagnostic method • Demonstrate that Santorini duct is dominant • Can induce pancreatitis

Treatment

• In symptomatic patient (pancreatitis)

• Goal• Establish adequate drainage of the Santorini duct

Treatment

• Treatment of choice• Sphincteroplasty of the minor papilla

• Endoscopic stenting +/-sphincterotomy

• Longitudinal pancreaticojejunostomy• Chronic pancreatitis with dilated duct

Treatment

Ectopic pancreatic rest

Ectopic pancreatic rest

• Frequently encountered along foregut derivatives e.g. stomach, duodenum, jejunum, colon

• Most common anomaly of gastric antrum • May be result of aberrant epithelial-mesenchymal interaction ->

trans differentiation of embryonic epithelium • Typically asymptomatic and encountered incidentally at

laparotomy or endoscopy • Usually not become inflamed, but can cause intestinal

obstruction or bleeding

Management

• Excision unless excision cause significant complication

Congenital short pancreas

Congenital short pancreas

• Unusual anomaly described in individuals with polyspleniasyndrome or isolated anomaly

• Pancreas appears blunted and lacks tissue in the region of body and tail (agenesis of dorsal pancreatic bud)

• Pancreatic function generally remains normal

Pancreatitis • Acute pancreatitis

• Chronic pancreatitis

Acute pancreatitis

Acute pancreatitis

• Acute inflammation of pancreas • Varying in severity • Acute recurrent pancreatitis

• Episode of inflammation completely resolve and then recur

• Incidence• 3.6-13.2 cases per 100,000 children

Histopathology

• Fulminant necrotizing pancreatitis • Diffuse stippled necrosis of pancreatic parenchyma and peripancreatic

fat

Cause

• Trauma• Fixed against lumbar spine

Cause

• Drug• Asparaginase• Didanosine• Azathioprine• Mercaptopurine • Valproic acid

• Biliary tract stone disease• Assoc with hemolytic disorder

e.g. spherocytosis, alpha-thalassemia, sickle cell disease

• Choledochal cyst• Duct compression • Bile reflux from long common

channel biliary-pancreatic duct • Assoc with malunion of

pancreatic and biliary ducts (pancreaticobiliary malunion)

Cause

• Systemic illness• CF• Reye syndrome• Hyperlipidemia• Hypercalcemia

• Infection• Kawasaki disease• Coxsackievirus, rota virus

• Liver transplant

• Ductal developmental anomalies• Pancreas divisum

• Metabolic derangements• Idiopathic ***

Pathophysiology

• Non physiologic calcium signaling in pancreas• Premature activation of acinar proenzymes (trypsin)

• Acinar cell injury + cytokine release

cytokine

Vascular dissemination

Free radical formation

Release of vasoactive substance

Extra pancreatic inflammation

Diagnosis

Criteria : 2/3 of the following • Acute abdominal pain (epigastric region)• serum amylase or lipase ≥ X3 of normal upper limit • Imaging

Diagnosis

• Physical examination• Diffuse tender with sign of peritonitis• Distension• Paucity of bowel sound • Grey Turner sign (Flank), Cullen sign(Umbilicus)

Severity

• Debanto et al 2002,• Respiratory failure : PaO2 < 60 mmHg• Renal failure : Cr > 2mg/dL, urine output < 0.3 ml/kg/h > 1 day• Pseudocyst development • Shock : need of vasopressor • Need operation • GI bleed• mortality

Pediatric acute pancreatitis severity (PAPS)

• At admission• Age < 7 years• Weight < 23 kg• WBC > 18,500• LDH > 2000

• At 48 hr after admission• Ca2+ < 8.3 mg/dK• Albumin < 2.6 g/dL• Fluid sequestration > 75

ml/kg/48 hr• Rise in BUN > 5 mg/dL

Investigation

• ↑ amylase, lipase• Lipase more sensitive in infant and toddler• Degree of elevation dose not correlate with severity

Hyperamylasemia

Salivary inflammation

Intestinal perforation/ischemia/necrosis

Hyperlipasemia

Pancreatic cancer

Macrolipasemia

Renal insufficiency

Hypertriglyceridemia

Imaging

• Plain abdominal film• Exclude intestinal perforation • Radiopaque gallstone• Gas-filled right colin • Isolated loop of intestine in the vicinity of

inflamed pancreas -> sentinel loop• Colon cut-off sign• Pancreatic calcification -> chronic

pancreatitis

• Chest film• Pleural effusion (left basal)• Pulmonary edema -> sign of systemic

cytokine releaseColon cut-off sign

Imaging

• Abdominal CT• Detect complication• Pancreatic necrosis• Pancreatic pseudocyst• Fluid collection

• Abdominal ultrasound • Evaluate biliary stone, choledochal cyst, pancreatic

pseudocyst(Hypoechoic or anechoic collection)

Imaging

Severe pancreatitis

Imaging

• MRCP• Evaluate pancreatic ductal anatomy in children with recurrent or

unexplained pancreatitis

Imaging

• ERCP• Rarely indicated for acute pancreatitis• Diagnosis or treatment of acute, recurrent, chronic pancreatitis • Avoid during acute phase• Can aggravate pancreatitis

Treatment

• Goal1. Minimize any causative factors2. Provide meticulous supportive care

Treatment

• Pain control : Fentanyl safer • Meperidine -> risk of seizure, euphoria, drug interaction • Morphine -> Sphincter of Oddi spasm

• IV resuscitation : Urine output > 2ml/kg/hr , retain Foley

• Pancreatic rest : • NPO, retain NG• Histamine-2(H2) receptor antagonist -> reduce exposure of duodenal

secretin-producing cells to gastric acid ( simulator of pancreatic secretion)

• Monitor complication• Beware of hypocalcemia, hypomagnesemia, anemia • Organ failure

Treatment

• Nutrition• Early nutrition within first 72 hrs• Preferred Enteral > total parenteral• No different of liquid or solid food as the initial meals

• ATB • No role of prophylactic• Imipenem is ATB of choice in necrotizing pancreatitis

• Somatostatin, glucagon, anticholinergics, histamine blockers, protease inhibitor • Recommended but not show conclusive benefit

Surgery

• Indication for exploration1. Infected necrotic pancreatitis 2. Pancreatic abscess

• PCD then minimal invasive necrosectomy

Complication

• Necrotizing pancreatitis

• Pseudocyst

• Ascites

• Pancreatic fistula

Ascites

• Uncontained leakage from major pancreatic ductal injury • CT, ERCP, MRCP should be performed if suspected• Mx

• Bowel rest• Nutrition• Long-acting of somatostatin analogs

• Can spontaneously resolve

Ascites

• Longer time can cause pseudocyst formation• In ductal injuries -> operation may needed

• Depend on nature and site of injury

Site of injury Mx of choice

Distal duct injury Pancreatic resection

Proximal injury Roux-en-Y jejunal onlayanastomosis

Pancreatic fistula

• Develop postoperative or from nonoperative management • Low output

• Spontaneous resolve • Long acting somatostatin accelerate closure

• Roux-en-Y jejunostomy anastomosed to the fistula in failed case

Chronic pancreatitis

Chronic pancreatitis

• Irreversibility of changes associated with the inflammation • Uncommon• 3-10 cases per 100,000• Recurrent episodes of upper abdominal pain assoc with varying

degrees of pancreatic exocrine and endocrine dysfunction

Pathogenesis

• Significant parenchymal and acinar destruction due to inappropriate activation of digestive enzymes + inflammation, fibrosis, loss of function

• Unknown pathogenesis• Repeat episodes of acute pancreatitis• Environmental trigger• Genetic susceptibilities• Factor lead to inflammatory response

Pathogenesis

Sentinel acute pancreatic event (SAPE)

activate

Normal pancreatic stellate cell

Myofibroblast-like cells

Clinical problems

1. Severe intractable pain (require narcotic)

2. Malabsorption require enzyme replacement for life

3. Life-threatening complication e.g. pancreatic pseudocyst, pancreatic ascites, biliary obstruction

4. 13-fold increased risk of pancreatic cancer

5. Development of insulinopenia and overt diabetes mellitus

Causes

• Hereditary• Trauma• Systemic disease• Malformation of pancreaticobiliary duct

• Pancreas divisum• Annular pancreas• Pancreaticobiliary malunion

Causes

Classification

Chronic calcifying pancreatitis

Hereditary• Cationic trypsinogen gene PRSS1, SPINK1, CFTR• Increased risk of pancreatic cancer after age 50

years

idiopathic

Assoc with intraductal pancreatic stones, pseudocyst, aggressive scar formation

Chronic obstructive pancreatitis

Anatomic or functional obstruction• Pancreas divisum• Choledochal cyst

Less scarring

Diagnosis

• Blood test : pancreatic enzyme• ↑ ≥ x3 of amylase/lipase• Stool test : pancreatic enzyme, fecal fat

• Pancreatic stimulation (secretin) test• Genetic testing in recurrent idiopathic pancreatitis with or

without family history • PRSS1 mutation, SPINK1, CFTR

Imaging

• Plain film• Calcification

• US• Dilation of pancreatic or biliary

duct• Calcification• Complication : pseudocyst,

abscess, calculi, ascites

Imaging

• CT• Delayed enhancement on arterial phase • Microcalcifications throughout parenchyma• Calcified stones in the duct • Dilated of main pancreatic duct +/- CBD (“double

duct sign”

• MRCP• Evaluate ductal anatomy• Causes of chronic pancreatitis

Calcified stone in dilated duct

Endoscopic Assessment

• ERCP• Gold standard in diagnosis of adult CP• 1-11% morbidity of post ERCP pancreatitis

• Endoscopic ultrasound (EUS)

Management

• Palliation of symptoms• Pain control and hydration• Pancreatic enzyme supplement in steatorrhea

• In severe pain• ERCP, MRCP help locate correctable problems such as large stone or

stricture with distal duct dilatation

Management

• Surgical option1. Sphincteroplasty2. Excision of localized pancreatitis3. Subtotal pancreatectomy 4. Pancreatic drainage

1. Longitudinal pancreaticojejunostomy (Puestow)2. Lateral pancreaticojejunostomy (modified Puestow procedure)3. End-to-end pancreaticojejunostomy (Duval)4. Frey procedure

5. Duodenum or pyrolus-preserveing whipple

Management

Management

To be continued…