What are the other Names for this Condition? (Also known as/Synonyms)

• Ampullary Tubular Adenoma
• Tubular Adenoma of Ampulla of Vater

What is Tubular Adenoma of Ampulla? (Definition/Background Information)

• Ampullary adenomas are common benign epithelial tumors arising in the ampulla of Vater. The ampulla of Vater is the region around the mouth where the common bile duct and pancreatic duct discharge into the duodenum, which is the upper part of the small intestine
• Tubular Adenoma of Ampulla is a common subtype of ampullary adenoma. The other types include villous adenoma of ampulla and tubulovillous adenoma of ampulla. These tumors are similar to adenomas seen in the small or large bowel
• It is generally considered to be a pre-malignant tumor, meaning that these tumors may turn malignant with time. If left untreated, they can develop into small bowel cancer. The potential for malignancy is lesser from a tubular adenoma than from a villous adenoma
• The cause of formation of Tubular Adenoma of Ampulla is reportedly due to genetic factors. Most adenomas are observed to form sporadically and are generally difficult to diagnose. Some are associated with a variety of syndromes, such as familial adenomatous polyposis or Gardner syndrome
• The signs and symptoms of Ampullary Tubular Adenoma may include obstructive jaundice, abdominal pain, fatigue, and unexplained weight loss. Complications, such as formation of gallstones, or compression of adjacent structures from large-sized tumors may occur
• The mainstay of treatment of Tubular Adenoma of Ampulla is surgical excision of the tumor, which may be performed via an endoscopic procedure or through surgical resection
• If Tubular Adenomas of Ampulla are detected early enough, they can be removed and their risk of development into a cancer is low. If, however, they have time to proliferate and grow, the risk for cancer may be high

Who gets Tubular Adenoma of Ampulla? (Age and Sex Distribution)

• Tubular Adenoma of Ampulla (sporadic tumors) typically occurs in middle-age to elderly individuals
• Both males and females are known to develop these tumors, although a female predominance is noted
• In the background of familial adenomatous polyposis, these adenomas are seen in younger individuals. Also, in such cases, no gender preference is noted
• No racial, ethnic, or geographical predominance is generally noted

What are the Risk Factors for Tubular Adenoma of Ampulla? (Predisposing Factors)

Common risk factors of Tubular Adenoma of Ampulla include:

• Aging: Elderly individuals have a higher risk for developing these tumors
• Presence of predisposing genetic conditions, such as familial adenomatous polyposis (FAP) or Gardner syndrome
• A family history of intestinal-type adenomas

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Tubular Adenoma of Ampulla? (Etiology)

Tubular Adenoma of Ampulla is caused by certain genetic mutations that lead to a condition termed dysplasia.

• Dysplasia is the phenomena of disordered growth of the epithelial lining of the colon. Genetic mutations lead to cell growths at abnormally high rates. This causes the cells to grow abnormally, forming the tumors characteristic of an adenoma
• Most tumors are noted to appear sporadically; while some appear in the presence of genetic disorders such as familial adenomatous polyposis (FAP) or Gardner syndrome
• The genetic mutations can be either inherited or caused on exposure to various environmental factors
  • Inherited genetic mutations include those that result from FAP or Gardner syndrome, which are autosomal dominant conditions
  • Environmental factors that cause genetic mutations may include radiation, harmful chemicals in the air, exposure to pollutants, and other such factors

FAP or Gardner syndrome involves germline mutations on the APC gene, located on chromosome 5. In such cases, the risk for formation of adenoma is almost 100%.

• Some FAP tumors show KRAS gene mutations
• BRAF gene anomalies are rarely noted
• Adenomas with high-grade dysplasia may show mutations on TP53 gene
• In some cases, the tumors show genetic abnormalities such as DNA mismatch repair and/or microsatellite instability (MSI)

Sporadic tumors show APC gene and KRAS gene mutations.

What are the Signs and Symptoms of Tubular Adenoma of Ampulla?

Many Tubular Adenomas of Ampulla present signs and symptoms, while some are asymptomatic and detected incidentally during an endoscopy. Most adenomatous tumors noted in the small bowel are present around the ampulla in the duodenum.

The signs and symptoms of Tubular Adenoma of Ampulla may include:

• Tumors at the ampulla of Vater may cause obstructive jaundice, even at small size
  • Obstruction of the bile ducts leading to jaundice also results in weight loss and pain in the abdomen
  • Yellowing of the skin and eye whites
  • It may also lead to pruritus, an intense itching sensation all over the body
• Inflammation of the pancreas (or pancreatitis) may be noted in some individuals
• Large tumors can frequently cause:
  • Abdominal (cramping) pain and discomfort
  • Swollen abdomen
  • Nausea and vomiting
• Presence of a palpable mass, when tumors are large
• Unexplained weight loss
• Narrowing of the intestine
• The tumors can be present anywhere in the ampullary region and may involve the peri-ampullary and duodenal regions too
• Most sporadic tubular tumors are smaller in size, when compared to villous tumors
• Polyp-shaped growth pattern is noted with tubular adenoma
• Sometimes, the polyps develop within the common bile duct, at the mouth (called intra-ampullary tumors)
• In the presence of a genetic disorder, multiple adenomatous tumors may be noted

How is Tubular Adenoma of Ampulla Diagnosed?

A diagnosis of Tubular Adenoma of Ampulla may include:

• Complete evaluation of family (medical) history, along with a thorough physical examination
• X-ray of the abdomen and pelvic region
• Barium enema X-ray
• Endoscopy: Capsule endoscopy is an effective tool for observing the small intestine along its entire length
• Liver function test
• Test for serum bilirubin levels
• CT or MRI scan of the abdomen and pelvic region
• Abdominal ultrasound scan
• Upper GI endoscopy: An endoscopic procedure is performed using an instrument called an endoscope, which consists of a thin tube and a camera. Using this technique, the radiologist can have a thorough examination of the insides of the gastrointestinal tract
• Endoscopic ultrasonography: During this procedure, fine needle aspiration biopsy (FNAB) can be performed on the affected area. This is good technique for tumor detection including tumor invasion parameters, and whether nearby lymph nodes are affected
• Endoscopic retrograde cholangiopancreatography (ERCP): It is a non-invasive diagnostic tool that can be used to visualize the bile ducts
• Imaging studies, such as MRI scan, scintigraphy, and PET scan, may be performed to detect tumor invasion and metastasis
• Tissue biopsy of the tumor:
  • A tissue biopsy of the tumor is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis
  • Biopsy specimens are studied initially using Hematoxylin and Eosin staining. The pathologist then decides on additional studies depending on the clinical situation
  • Sometimes, the pathologist may perform special studies, which may include immunohistochemical stains, molecular testing, and very rarely, electron microscopic studies to assist in the diagnosis

Note: Ampullary adenomas obstructing the pancreatic and bile duct may present increase in serum levels of compounds such as bilirubin, glutamic transaminase, and alkaline phosphatase.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Tubular Adenoma of Ampulla?

The complications of Tubular Adenoma of Ampulla may include:

• Some individuals develop stones in the gallbladder or bile duct
• The tumors may develop to form ampullary adenocarcinomas, if undetected or left untreated. Majority of invasive carcinomas in the region are seen with intestinal adenomas
• Complications may arise from the underlying genetic disorder, if present
• Large-sized tumors may compress adjoining tissues and structures resulting in additional complications
• Damage to the muscles, vital nerves, and blood vessels, during surgery
• Post-surgical infection at the wound site is a potential complication

How is Tubular Adenoma of Ampulla Treated?

Treatment measures for Tubular Adenoma of Ampulla may include:

• When the tumor is confined to the surface, an endoscopic mucosal/submucosal resection (or surgical removal via endoscopy) is undertaken
• Surgical removal of the entire tumor may be the preferred method of treatment (polypectomy or surgical resection)
• If lesions are large, then it may not be possible to remove through endoscopy. In such cases, they are removed through transduodenal ampullectomy or pancreatoduodenectomy
• Tumors near the pancreatic duct outlet may be treated through a surgical technique termed pancreaticoduodenectomy (or Whipple procedure)
• Undertaking treatment of underlying genetic disorder, as necessary

Regular observation and periodic checkups to monitor the condition is strongly recommended following treatment.

How can Tubular Adenoma of Ampulla be Prevented?

Currently, there are no known preventative measures against Tubular Adenoma of Ampulla. However, if the tumor is associated with a genetic disorder, the following points may be considered:

• Genetic counseling and testing: If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Regular health check-ups might help those individuals with a history of the condition in the immediate family and help diagnose the tumor early

Regular medical screening at periodic intervals with blood tests, scans, and physical examinations, are mandatory. Often several years of active vigilance are crucial and necessary.

What is the Prognosis of Tubular Adenoma of Ampulla? (Outcomes/Resolutions)

With prompt diagnosis and removal of the tumor, the prognosis of Tubular Adenoma of Ampulla is typically good. In such cases, the tumor may be small-sized and may not have transformed into a malignancy.

• Tubular adenoma is less often associated with a carcinoma or a high-grade dysplasia, unlike a villous adenoma. Hence, the potential for malignancy is lesser from a tubular adenoma than from a villous adenoma
• Large-sized adenomas in individuals with a genetic disorder (such as FAP) and seen with high-grade dysplasia, show a greater potential for adenocarcinoma development

Additional and Relevant Useful Information for Tubular Adenoma of Ampulla:

The following DoveMed website links are useful resources for additional information:

http://www.dovemed.com/diseases-conditions/cancer/