Ampullary Carcinoma

A rare malignant tumor originating at the ampulla of Vater, in the last centimeter of the common bile duct, where it passes through the wall of the duodenum and ampullary papilla.

Signs and symptoms

1.           Secondary to biliary obstruction:

a.        Pancreatitis (May be the first clinical manifestation, due to obstruction of the pancreatic duct)

b.        Jaundice (most common clinical presentation)

c.         Pruritus

d.         Courvoisier gallbladder (ie, a distended, palpable gallbladder in a patient with jaundice)

*Courvoisier sign or Courvoisier-Terrier's sign states that in a patient with painless jaundice and an enlarged gallbladder (or right upper quadrant mass), the cause is unlikely to be gallstones and therefore presumes the cause to be an obstructing pancreatic or biliary neoplasm until proven otherwise.

2.           Diarrhea, Weight loss, Malaise

3.           Abdominal pain

4.           Dyspepsia, Anorexia

5.           Nausea, Vomiting

6.           Fever/chills
*particularly when the biliary tract has been explored previously (eg, after common duct exploration for stones, or after endoscopic retrograde cholangiopancreatography [ERCP]).

7.           Upper GI bleed & heme positive stools, may occur due to ulceration of ampullary mass (less common)

Pathophysiology

1 of 4 epithelial types:

(1) terminal common bile duct

(2) duodenal mucosa

(3) pancreatic duct

(4) ampulla of Vater

Ÿ   Each type of mucosa produces a different pattern of mucus secretion.

Ÿ   Ampullary tumors secreting sialomucins had a better prognosis (100% vs 27% 5-y survival rate)

Ÿ   The 5-year survival rates were markedly different between tumors that expressed CA 19-9 and those that did not (36% vs 100%)

Ÿ   Immunohistochemical stains for expressions of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9, Ki-67, and p53 have been studied for prognostic power.

Epidemiology

relatively uncommon tumor that accounts for approximately 0.2% of gastrointestinal tract malignancies and approximately 7% of all periampullary carcinomas

Diagnostic Considerations

Ÿ   Carcinoids

Ÿ   Neuroendocrine tumors

Ÿ   Gastrointestinal stromal tumors (GISTs)

Ÿ   Lipomas

Ÿ   Adenomyomatosis

Differential Diagnoses

Ÿ   Bile Duct Strictures

Ÿ   Bile Duct Tumors

Ÿ   Carcinoma of the Ampulla of Vater

Ÿ   Cholangiocarcinoma

Ÿ   Gallbladder Cancer

Ÿ   Non-Hodgkin Lymphoma

Ÿ   Pancreatic Cancer

Laboratory Studies

1.           Complete blood cell count

2.           Electrolyte panel

3.           Liver function studies

a.      prothrombin time

b.      bilirubin [direct and indirect]

c.      transaminases

d.      alkaline phosphatase)

4.           Cancer antigen 19-9 (CA 19-9)
*elevated in pancreatic malignancies

5.           Carcinoembryonic antigen (CEA)
* elevated in patients with other gastrointestinal malignancies (in particular, colon and rectal cancer), the possibility of a second primary tumor

Imaging Studies

Ÿ   Ultrasonography

1.           initial study to evaluate the common bile duct or pancreatic ducts

2.           Both ultrasound and CT can help reveal metastatic disease in the liver or regional lymph nodes

Ÿ   Computed tomography

1.           demonstrates a mass but is not helpful in differentiating ampullary carcinoma from tumors of the head of the pancreas or periampullary region.

2.           If the lesion is smaller than 2 cm, pancreatic or bile duct dilation might be the only abnormalities noted on CT scan

Ÿ   Endoscopic ultrasound

1.           biopsy of the tumor via fine needle aspiration (FNA)

2.           for lymph node metastasis (evaluate regional lymph nodes)

3.           for vascular invasion (celiac and superior mesenteric vessels to evaluate)

Ÿ   Endoscopic retrograde cholangiopancreatography

May suggest dx:

a.           Irregular pancreatic duct narrowing

b.          Displacement of the main pancreatic duct

c.           Destruction or displacement of the side branches of the duct

d.          Pooling of contrast material in necrotic areas of tumor

Ÿ   Positron emission tomography

a means of imaging the metabolic activity of a particular tumor.

Staging

The classification system of Yamaguchi and Enjoji is similar to the Martin classification:

Stage I	Vegetating tumor limited to the epithelium with no involvement of the sphincter of Oddi
Stage II	Tumor localized in the duodenal submucosa without involvement of the duodenal muscularis propria but possible involvement of the sphincter of Oddi
Stage III	Tumor of the duodenal muscularis propria
Stage IV	Tumor of the periduodenal area or pancreas, with proximal or distal lymph node involvement

American Joint Committee on Cancer staging system (7th edition)

Ÿ   Primary tumor is defined as follows: TX – Primary tumor cannot be assessed T0 – No evidence of primary tumor Tis – Carcinoma in situ T1 – Tumor limited to ampulla of Vater or sphincter of Oddi T2 – Tumor invades duodenal wall T3 – Tumor invades pancreas T4 – Tumor invades peripancreatic soft tissues or other organs Ÿ   Regional lymph nodes are defined as follows: NX – Regional lymph nodes cannot be assessed N0 – No regional lymph node metastases N1 – Regional lymph node metastases (peripancreatic lymph node metastasis, including lymph nodes along the hepatic artery and portal vein) Ÿ   Distant metastases are defined as follows: MX – Presence of distant metastases cannot be assessed M0 – No distant metastases M1 – Distant metastases

Surgical Care

pancreaticoduodenal resection (Whipple procedure):

1.           The gastric antrum and duodenum

2.           A segment of the first portion of the jejunum, gallbladder, and distal common bile duct

3.           The head and often the neck of the pancreas

4.           Adjacent regional lymph nodes

Factors associated with the presence of lymph node metastasis included the following:

1.           Tumor size ≥1 cm

2.           Poor histologic grade

3.           Perineural invasion, Microscopic vessel invasion

4.           Depth of invasion > pT1

5.           T stage (T1, 28.0%; T2, 50.9%; T3, 71.7%; T4, 77.3%; P < 0.001)

*5-year survival rates have ranged from 20-61%, averaging higher than 35%

Reference: Medscope