Healthcare Professionals
Periampullary Tumors
Periampullary tumors originate from the head of the pancreas, the ampulla of vater, distal common bile duct and the duodenum. They constitute 30% of malignant tumors that arise from the pancreatic head region. The periampullary region constitutes the ampulla and the duodenal mucosa. It contains two types of epithelia; the duodenal intestinal type and the pancreaticobillary type which can be distinguished histologically. Periampullary tumors and cancers display unique characteristics due to their site specific origin.
Etiological factors for periampullary carcinoma are smoking, diet high in fat and protein and low in fruits and vegetables, coffee consumption, alcohol and diseases like diabetes mellitus, chronic pancreatitis, pernicious anemia, cholelithiasis and previous gastric surgery.
- Pathology of tumors in the periampullary region
These tumors are derived either from the epithelium, the connective tissue, the lymphoid tissue or the neuroendocrine cells. Tumors derived from the epithelium are more common as compared to those derived from the other parts. WHO has not classified periampullary tumors separately but have included them in the classification of tumors of small intestine. Table 1 shows the classification of tumors occurring in the periampullary region.23
| WHO classification of tumors of periampullary region |
1. |
Epithelial tumors |
|
|
Benign |
Adenoma |
|
Pre-malignant lesions |
Dysplasia |
|
Malignant |
Adenocarcinoma |
2. |
Neuroendocrine tumors |
‘Carcinoids’ gangliocytic paraganglioma |
3. |
Stromal tumors |
Gastrointestinal stromal tumor (GIST) |
|
|
Lipoma |
|
|
Kaposi’s sarcoma |
|
|
Others |
4. |
Malignant lymphomas |
|
5. |
Secondary tumors |
|
6. |
Hyperplastic polyps, adenomyomatous hyperplasia, pancreatic heterotopia |
|
Epithelial tumors
- They are very rare (0.4 per 100,000 per year)
- Periampullary adenomas and carcinomas show a hereditary tendency and other etiological factors like familial adenomatous polyposis, hereditary non-polyposis colonic carcinoma, Peutz-Jeghers syndrome, juvenile polyposis syndrome and association with Crohn's disease and celiac disease.
Epithelial tumors are have been assigned a separate classification. Table 2 shows the TNM staging of periampullary tumors24, 25
Tumor stage: (pT) |
Tx |
Primary tumor cannot be assessed |
To |
No evidence of primary tumor |
Tis |
Carcinoma in situ |
T1 |
Tumor limited to ampulla of Vater (not beyond sphincter of Oddi) |
T2 |
Tumor invades duodenal wall |
T3 |
Tumor invades pancreas |
T4 |
Tumor invades peri-pancreatic soft tissues or other adjacent organs or structures |
Regional lymph nodes (N): |
Nx |
Regional lymph nodes cannot be assessed |
N0 |
No regional lymph node metastasis |
N1 |
Regional lymph node metastasis |
Distant metastasis (M): |
Mx |
Distant metastasis cannot be assessed |
M0 |
No distant metastasis |
M1 |
Distant metastasis |
Premalignant lesions of the periampullary region
- The adenomas are classified into tubular adenoma, tubullo-villous adenoma and villous adenoma.
- Adenomatous tissues have been found in 40 to 80% of invasive sporadic adenocarcinomas.
- Multiple biopsies are required to rule out an underlying invasive adenocarcinoma in an adenomatous lesion.
Carcinoma of the periampullary region
- Periampullary carcinomas are 2 to 3 cm in diameter and are divided into 3 forms; intramural protruding, exposed protruding and ulcerating form.
- There are major differences between non-pancreatic periampullary and pancreatic carcinoma invading the periampullary region.
Differences between non-pancreatic and pancreatic periampullary carcinoma
Non-pancreatic periampullary carcinoma |
Pancreatic carcinoma invading periampullary region |
Smaller size |
Larger size |
Better differentiation |
Poorer differentiation |
Low nodal stage |
High nodal stage |
Margins negative |
Margins positive/negative |
Less incidence of vascular invasion |
High incidence of vascular and nerve invasion |
90% resectability |
40% resectability |
Median survival 38 months* |
Median survival 15 months* |
* Median survival in patients undergoing resection with curative intent |
Neuroendocrine tumors (NET)
- They are rare and constitute 22% of GI endocrine tumors.
- They are of 5 types; gastrin-producing NET, somatostatin producing NET, serotonin/calcitonin producing tumors, poorly differentiated NET and gangliocytic paraganglioma.
Lymphomas
- The types of lymphomas that affect the periampullary region are follicular lymphoma, marginal zone lymphoma, diffuse large β-cell lymphoma and mantle cell lymphoma.
- Follicular lymphomas occur around the ampulla.
- Diffuse large β-cell lymphomas are very similar to carcinomas.
Stromal tumors
- These are rare tumors and are of different types like gastrointestinal stromal tumors (GISTs), lipomas, nerve sheath tumors and other sarcomas.
Metastatic tumors
- Duodenal metastases are usually found in the periampullary region.
- Tumors that metastasise to the ampulla are malignant melanoma, carcinoma of the lung, genito-urinary cancers, breast cancer, Kaposi's sarcoma, colonic carcinoma and renal cell carcinoma.
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