Ampullectomy

The first localized resection of an ampullary lesion was performed transduodenally by Halsted in 1899. Since Halsted’s time, technologic advancements have enhanced the array of tools at the disposal of the modern surgeon. In modern times, ampullectomy can be performed as an endoscopic mucosal resection (EMR) or as a full-thickness resection via duodenotomy by way of laparoscopy or open surgery.[1, 2]  Surgical ampullectomy remains a useful treatment option for ampullary lesions, but its utility is limited to a narrow range of indications.[3, 4, 5, 6]

Neoplasms of the ampulla of Vater are a small subset of the broader category of biliary tract neoplasms. These lesions demand separate consideration from their biliary counterparts because of their unique location and behavior. In general, localized resection of papillary, ampullary, and periampullary neoplastic lesions should be considered only if these lesions are benign. Malignant disease of this region is associated with extraordinarily high recurrence rates (approximately 80% local recurrence with malignant disease and up to 40% local recurrence with nonmalignant dysplasia) with local resection alone, mandating radical resection via pancreaticoduodenectomy.

Although there has been some discussion regarding the role of ampullectomy in limited circumstances with regard to malignant Tis and T1 ampullary carcinoma,[7, 8] this article addresses the details of surgical ampullectomy for benign neoplasia of the ampulla of Vater.

In addition, endoscopic technology and tools for periampullary procedures represent a broad subject that discussed more widely elsewhere.[9, 10, 11, 12] The present article focuses on the details of open surgical ampullectomy, with acknowledgement of laparoscopy as a valid technologic variant that is at the disposal of the surgeon who has already mastered open surgical ampullectomy. Robotic transduodenal ampullectomy has also been described.[13]

Histopathologic variants of ampullary neoplasia

Ampulla of Vater neoplasias include a diverse array of lesions, including those that arise from genetic predisposition, spontaneous mutation, or spontaneous occurrence. The earliest manifestation of disease occurs in the common channel of the ampulla, perhaps reflecting a mutagenic nature of bile. The most common cause of heritable ampullary neoplasia is familial adenomatous polyposis (FAP), which progresses from adenoma to malignancy along the well-described pathway of mutagenesis for colon cancer.

Variants include the following:

• Adenoma to adenocarcinoma of the ampulla - These include FAP and hereditary nonpolyposis colorectal cancer ^[14]
• Squamous cell carcinoma of the ampulla
• Neuroendocrine tumors of the ampulla
• Well-differentiated carcinoid tumors - These have unpredictable behavior patterns, are often asymptomatic, have unpredictable recurrence rates, and are difficult to diagnosis with endoscopy
• Granular cell tumors of the ampulla
• Benign lesions - These include lipomas, paraganglionomas, other tumors of neurogenic origin, lymphangiomas, leiomyofibromas, adenomatous polyps, and small intraductal benign adenomas of the common bile duct (CBD)

Discrete limitations apply to lesions that lend themselves to successful surgical ampullectomy. This procedure is indicated for benign disease of the ampulla with lesions that are smaller than 2 cm and are located within 2 cm of the ampulla.[15, 16, 17]

It has been suggested that ampullectomy may also be considered for early (eg, pT1) ampullary cancers in patients at high operative risk with pancreaticoduodenectomy if the lesion is small (≤ 1 cm), well differentiated, and of polypoid gross morphology.[18, 19]  Nodal clearance may be required for long-term survival in this setting.[20]

Contraindications for surgical ampullectomy include the following:

• Malignant periampullary lesions
• Large periampullary lesions
• Benign periampullary lesions more than 2 cm away from the ampulla
• Pancreatic lesions
• CBD tumors larger than 1.5 cm

Larger benign lesions and those of any size that are located more than 2 cm away from the ampulla do not qualify for surgical ampullectomy. Larger lesions may harbor foci of malignancy, and at increasing distance from the ampulla, reasonable anatomic reconstruction becomes impossible. Finally, surgical ampullectomy is not indicated for lesions that arise in the context of clinical cues of malignancy (unintended weight loss, jaundice, ascites).

Surgical ampullectomy is also contraindicated for lesions with an unclear tissue diagnosis or fine-needle aspiration (FNA) with no evidence of malignancy in the presence of clinical cues of malignancy.

Complication prevention

The following measures are used for complication prevention:

• Thorough preoperative evaluation
• Sequential compression devices for prevention of deep vein thrombosis
• Preoperative biliary decompression if a surgery delay is expected or preoperative cholangitis is present
• Nasogastric decompression to prevent duodenal distention

Because surgical ampullectomy involves significant dissection and manipulation of periduodenal anatomy, patients selected for this procedure must be able to tolerate major surgery. Thorough preoperative evaluation and imaging must contribute to operative planning (see below). In addition, the patient must be counseled that if malignancy is detected, the more radical resection of pancreaticoduodenectomy is indicated.

An extensive patient history should be taken to detect heritable patterns. A thorough physical examination is performed to identify contraindications for local resection. A preoperative evaluation is carried out to assess fitness for surgery and anesthesia; this includes cardiac risk factors, nutritional status, functional status, and American Society of Anesthesiologists (ASA) class.

Laboratory tests include a complete blood count (CBC), basic metabolic panel, liver function tests (LFTs), coagulation panel, cancer antigen (CA) 19-9, and carcinoembryonic antigen (CEA).

Preoperative imaging includes the following:

• Computed tomography (CT) pancreatic protocol or magnetic resonance cholangiopancreatography (MRCP) to evaluate for local complications (eg, biliary obstruction or pancreatitis) or metastatic disease (eg, malignant adenopathy or distant metastases)
• Endoscopic ultrasonography (EUS), with or without fine-needle aspiration (FNA), to detect transmural invasion, ductal involvement, and nodal metastases, as well as tissue diagnosis, is used for clinical staging ^[21] ; because FNA yields false-negative malignancy results in 40% of cases, clinical suspicion of malignant disease should not be ignored

Clinical cues of malignancy include the following:

• Unintended weight loss
• Jaundice, ascites, cholangitis
• Biliary dilatation, pancreatic duct dilatation
• Ulcerated lesion or hard tumor during EUS or FNA
• High-grade dysplasia on FNA histopathology
• Elevated CA 19-9 levels in the absence of biliary obstruction
• Elevated CEA levels

A gastrointestinal specialist should be consulted for endobiliary stent placement for decompression if it is anticipated that surgery may be delayed.

Equipment for ampullectomy includes the following:

• Arterial and central venous lines for hemodynamic monitoring
• Nasogastric tube
• Foley catheter
• Secretin for difficult-to-localize pancreatic duct
• Glucagon for a difficult-to-localize common bile duct (CBD)
• Radiopaque balloon-tipped catheters for cannulation of the CBD and pancreatic duct
• Removable pancreatic stent (5 French)
• Closed-suction transabdominal drains
• Fluoroscope and operator
• Patient and surgical team prepared for conversion to pancreaticoduodenectomy if intraoperative pathologic analysis reveals evidence of malignancy

General anesthesia is used for surgical ampullectomy.

The patient is placed in the supine position.

Surgical ampullectomy mandates close follow-up. Duodenoscopy is performed at 3-6 months for evaluation and pancreatic duct stent removal, every 6 months for 2 years afterward, and once yearly thereafter for surveillance. Strictures are interrogated and biopsied to evaluate for local recurrence. Recurrent disease is an indication for pancreaticoduodenectomy.

The procedural details below are focused on open surgical ampullectomy. Endoscopic approaches, including snare excision, endoscopic mucosal resection (EMR), and ablation techniques, are not discussed here.

Laparotomy and evaluation

After the patient is properly positioned and general anesthesia induced, a generous midline incision or right subcostal incision is created. The abdomen is first explored to detect any malignant disease, though if adequate preoperative imaging was carried out, malignancy will rarely be found. Still, the liver is palpated and the peritoneum inspected before further steps are embarked on.

Exposure of duodenum and ampulla

The ascending colon and hepatic flexure are mobilized and an extended Kocher maneuver performed. Once the duodenum and the pancreatic head are adequately mobilized from their retroperitoneal attachments, a laparotomy sponge can be placed behind the duodenum to facilitate ideal positioning, or it can simply be grasped by the surgeon’s left hand and held in position. At this point, the ampulla and lesion are palpated from outside the duodenum by digital compression of the lateral duodenal wall against the medial wall of the duodenum until the aforementioned structures are palpated.

A longitudinal duodenotomy is then created on the lateral wall of the duodenum. Stay sutures are placed at the 9 o’clock and 3 o’clock positions on the anterior and posterior leaflets of the duodenotomy to facilitate exposure of the underlying ampulla.

Resection

A cholecystectomy is performed, and the common bile duct (CBD) is interrogated with antegrade transcystic placement of a radiopaque balloon-tipped catheter. The distal end of this catheter should enter the duodenal lumen via the ampulla. The pancreatic ductal opening may or may not be visible at this time.

The lesion or lesions are now evaluated. A submucosal saline injection can be used to further evert the lesion toward the surgeon, though this maneuver is not helpful with full-thickness lesions. A needle-tip electrocautery is used to excise superficial lesions that do not involve the CBD, pancreatic duct, or common channel, and cautery dissection progresses through pancreatic parenchyma as appropriate for lesions with transmural invasion or CBD, pancreatic duct, or common-channel extension. The goals of resection are negative margins ranging from 5 mm to 1 cm around the lesion, as possible.

Generally, resection continues from the 11 o’clock position around the lesion in a clockwise manner to the 3 o’clock position and is halted until a suture is placed at the bile duct orifice to marsupialize it, or spatulate the mucosa. Subsequently, careful dissection continues until the pancreatic duct is seen. If it is not easily detected, secretin can be used to stimulate pancreatic secretion and locate the pancreatic duct opening. Similarly, glucagon can be used to facilitate location of the bile duct papilla. Once the pancreatic papilla has been identified, circumferential resection is completed, and the specimen is then passed off the table after being oriented for pathology.

Reconstruction

If specimen margins are positive or malignancy is identified, pancreaticoduodenectomy must then be undertaken. If not, the ductal anatomy can be reconstructed. The bile duct might require further spatulation, and circumferential interrupted absorbable sutures are placed (with the help of optical magnification) around the bile duct orifice and around the pancreatic duct orifice to the duodenal mucosa. The pancreatic duct may also be stented at this time or sphincterotomy performed to prevent severe acute postoperative pancreatitis and strictures.

The longitudinal duodenotomy is then closed—transversely if possible, longitudinally if not—by using any of a number of handsewn anastomotic options. Closure may be accomplished in a running fashion or with interrupted sutures, with either a one-layer or a two-layer anastomosis, and in a transverse or (less commonly) a longitudinal fashion, with or without an overlying omental pedicle flap. At the completion of anastomosis, a closed-suction drain is placed at the duodenal anastomosis transcutaneously, exiting at the right upper quadrant. The abdomen is then closed in a standard fashion.

Nasogastric tubes can often be removed within 24-48 hours after surgery. Transcutaneous closed-suction duodenotomy drains can be removed once oral intake has been undertaken without complication.

Antibiotic use depends on preoperative biliary obstruction or the presence of cholangitis.

Early complications of open ampullectomy include the following:

• Acute pancreatitis (~12% of cases; this is milder in presentation if a pancreatic duct stent is placed)
• Intraduodenal hemorrhage (~10% of cases)
• Cholangitis or sepsis
• Duodenal, pancreatic, or biliary leak
• Enteric perforation (rare)
• Perioperative death (rare)

Late complications include the following:

• Duodenal, pancreatic, or biliary stricture
• Local recurrence of dysplastic lesions
• Distant recurrence of malignant disease