Periampullary Carcinoma

Periampullary tumors -Management R.Srivathsan

Endoscopic View

Pathology  Adenocarcinoma

accounts for 95%  Arises from 4 different tissues of origin • Head of pancreas (40-60%) • Ampulla of Vater (10-20%) • Distal Bile duct (10%) • Periampullary duodenum (5-10%) • Could be that pancreatic causes account for abt 90% cases.

Pathology  Prognosis

for each of these are different.  Five year survival for pancreas: 18%  Five year for ampulla: 36%  Five year for distal bile duct: 34%  Five year for duodenum: 33%  Determination of tissue origin is important for prognosis, extent of resection.

Pathology  Determination

of tissue origin from FNA, endoscopic biopsy.  Also from thin section CT scan, ERCP  Determination of k-Ras also helps (95% of pancreatic cancer).

Spread  Locoregional

spread results from lymphatic invasion and direct tumor spread to adjacent soft tissue.  Ampullary lesions spread to LN 33%, typically to a single LN in the posterior pancreatcoduodenal group.  Duodenal has intermediate spread.  Pancreas metastasizes 88% to multiple sites.

Treatment  Standard

Whipple pancreaticoduodenectomy thought to provide adequate tumor clearance in the case of non-pancreatic ampullary tumor, because tumor spread is localized.  Biopsy proven paraduodenal LN is thought by most to preclude curative resection

Surgery and Chemotherapy  Retrospective

review of 41 patients identified low risk and high risk patients determined by pathology.  Low risk: limited to ampulla or duodenum, well differentiated, negative margins and LN.  High risk: tumor invasion of pancreas, poorly differentiated, positive margin, positive LN.

Surgery and Chemotherapy  Low

risk patients had 5 year local control and survival of 100% and 80% respectively.  High risk patients had 5 year local control and survival of 50% and 38%, respectively.  Based on these findings, some have proposed a course of preoperative chemoradiation to improve local disease control in these high risk patients.

Whipple Procedure  Five

basic techniques are used to resect pancreatic cancers.  Standard pancreaticoduodenectomy  Pylorus preserving pancreaticoduodenectomy  Total pancreatectomy  Regional pancreatectomy  Extended resection (MD Anderson)

Whipple Procedure  Thorough

abdominal exploration by laparoscopy should proceed resection.  There is no role for resection in presence of metastatic disease.  Exploration includes inspection of liver, peritoneal surfaces, paraaortic LN, root of mesentery.

Whipple Procedure  Mobilize

right colon and terminal ileum  Open Lesser sac, which exposes anterior surface of pancreas, SMV at inferior border.  Duodenum is mobilized (Kocher) until IVC and renal veins are visualized.  Assess relationship of tumor to SMA by palpation.  Cholecystectomy done to facilitate dissection of structures in gastroduodenal ligament.

Kocherizing

Kocherizing the Duodenum

Vessel Involvement

SMA Involved?

Whipple Procedure  Dilated

CBD is divided proximal to cystic duct, which allow identification of portal vein and its relationship to pancreas.  Periportal LN are biopsied and frozen sectioned.  Hepatic artery is followed proximally to gastroduodenal artery which is divided at its origin.

Whipple Procedure  Stomach

is divided, or first portion of duodenum if pylorus preserving.  Although CBD and proximal GI tract has been divided, you can still abort and bypass.  Proximal jejunum dissected from its mesentery and divided.  Pancreas divided overlying SMV, venous branches ligated to head and uncinate process.

SMV Identification

Dividing the Neck

Whipple Procedure  Specimen

is now only attached to retroperitoneum and SMA.  SMA skeletonized to its origin, the tissue dissected from the SMA represents the retroperitoneal margin.  Ligate inferior pancreaticoduodenal artery, preserve possible aberrant right hepatic if seen.

The End Result

Pylorus Preserving  Introduced

in 1978 in an attempt to eliminate postgastrectomy syndromes.  It does not adversely affect local control or survival. Blood loss and operative time less.  Only differs in that blood supply to proximal duodenum is preserved (preserve right gastroepiploic arcade after ligation of gastroepiploic artery and vein at its origin).

Intraoperative  Morbidity

and mortality for pancreatic resections are greater than those seen after other operations.  Patients and families must be informed of potential complications, especially when there is no preoperative confirmation of diagnosis.  Neoplasms of the head can cause pancreatitis making definitive diagnosis difficult.

Intraoperative  Intraoperative

transduodenal biopsy may show inflammation ,but does not rule out malignancy.  Occasionally you suspect malignancy but cannot confirm radiologically or histologically.  Potential morbidity of resecting benign disease is preferred over leaving a curative lesion in situ.  Inform patients that resection may be required without confirmation of malignancy.

Surgical Results  Many

physicians have adopted a nonoperative or palliative approach to pancreatic cancer due to previously high operative morbidity and mortality rates.  Morbidity rates were 50% in 60s, not less than 25%.  Mortality rates low as 3% in most recent reviews.

Complications Postoperatively  Sepsis

13%  Fistula 10%  Biliary fistula 5%  Renal failure 13%  Hemorrhage 10%  Pancreatitis 2%  Cardiac 5%

Complications

Prognosis  Little

change in survival.  Remains less than 25% over 5 years  Median survival in 20 months  Body and tail have worse prognosis because detected late, advanced disease.  MD Anderson does more than 50 Whipple procedures over a three year period.

Mortality and Volume of Surgery

5 year survival, morbidity, mortality

Adjuvant Therapy  Autopsy

series show that 85% of patients will experience recurrence in operative field.  70% have metastases to liver.  So need to address local control (radiation) and distant disease (chemotherapy).  Most commonly used is 5 FU and this only has a 15-28% response on its own, but it’s a radiosensitizer, so it improves response to chemo.