Type:
Educational Exhibit
Keywords:
Not applicable, Metastases, Diverticula, Cancer, Biopsy, CT, Small bowel, Gastrointestinal tract, GI Tract
Authors:
M. Badulescu1, M. D. COMSA2; 1Cluj Napoca/RO, 2Cluj Napoca, Cl/RO
DOI:
10.26044/ecr2020/C-09946
Background
Epidemiology and pathogeny of duodenal masses
Primary malignant tumors of the duodenum are rare conditions, but they cumulate up to 50% of small bowel malignancies. The most frequent tumor of the duodenum is adenocarcinoma. Other primary tumors are lymphomas, neuroendocrine tumors, stromal tumors [1].
Adenocarcinoma accounts for up to 80—90% of all primary duodenal malignant tumors [2].
- It has a peak incidence in the 7th decade and it’s very aggressive, with quick evolution towards metastasis and invasion of the retroperitoneal fat planes or other organs.
- Familial adenomatous polyposis, Gardner syndrome and duodenal polyps are risk factors for developing adenocarcinoma [3].
Duodenal lymphoma may be primary or secondary in patients with diffuse lymphomatous disease.
- Mostly in the duodenum develops non-Hodgkin T-cell lymphoma, from the lymphatic tissue of the lamina propria.
- It causes duodenal wall thickening and diffuse involvement, but small bowel obstruction is uncommon [2].
Neuroendocrine neoplasms (NEN) develop frequently in the gastrointestinal tract, but only 3% of them are located in the duodenum.
- The majority of duodenal NEN originate from the first and second portions of the duodenum [2].
- Neuroendocrine neoplasms (NENs) can be benign or malignant and develope from the neuroendocrine cell system.
- There are two types of neuroendocrine neoplasms: neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs).
- Neuroendocrine tumors are defined as well-differentiated, low-proliferating NENs, whereas NECs are defined as poorly differentiated, high-proliferating NENs [4].
- The majority of duodenal NEN (62%) are gastrin cell (G cell) tumors and 21% of them are somatostatin-producing (D cell) tumors developing exclusively in and around the ampulla of Vater.
- Duodenal NEN may be included in clinical syndromes: Zollinger-Ellison syndrome, multiple endocrine neoplasia type 1 (MEN-1) or neurofibromatosis type 1 (NF-1) [2].
Gastrointestinal stromal tumors (GISTs)
- GISTs are solitary masses; they originate from the interstitial cells of Cajal.
- The origin is intramural, but they can grow endoduodenal, extrinsic, or have a “dumbbell” shape.
- When GISTs enlarge, they may present central necrosis and ulceration caused by an increased blood supply.
- They can become malignant along with the growth of the tumor; however, the final diagnosis of malignancy can be established only microscopically. [5]
Metastatic disease is uncommon in the duodenum, but when it occurs the cause may be melanoma, lung carcinoma, renal cell carcinoma or seminoma [2].
There are also benign conditions that may develop in the duodenum, such as adenomatous polyps, hamartoma (with an epithelial origin), lipoma, some GISTs (with intraluminal development), diverticulum ( Table 1). [2,6].
Additionally, the duodenum can be involved in other organs pathology, either through invasion or systemically.
- Gastric tumors that originate from pylor can extend also towards the duodenum and cause obstruction or possible hemorrhages.
- Hepatic pathology such as tumors or varices can affect the duodenum by narrowing its lumen.
- Tumoral or chronical pancreatic conditions can also involve the duodenum.