Discussion
Duodenal lesions are a rare finding in patients submitting to upper
endoscopy, with studies reporting rates from less than 1% to 5%1,2, even if their incidence has increased with the
improvement of advanced endoscopic techniques and the widespread use of
upper gastrointestinal endoscopy; most of duodenal lesions are detected
incidentally during EGD, that is performed for other gastrointestinal
issues.
Patients with duodenal lesions are often asymptomatic; when they occur
with symptoms, these include dyspepsia, abdominal pain, obstruction,
gastrointestinal bleeding. Duodenal lesions can be divided into
sub-epithelial lesions, such as lipomas, gastrointestinal stromal
tumours (GISTs) and carcinoids, and mucosally-based lesions, such as
Brunner’s gland adenomas or hamartomas, solitary Peutz-Jeghers polyps
and ampullary or not-ampullary adenomas.
The diagnostic assessment of these lesions is important to guide the
appropriate treatment: the visual endoscopic appearance allows to
differentiate neoplastic lesions from others with no malignant potential
by using magnification endoscopy, chromoendoscopy and high-definition
narrow-band imaging (NBI) for the evaluation of morphological features
and the pit pattern. Endoscopic ultrasonography is also an effective
imaging modality that allows real-time assessment of a lesion’s depth of
invasion and nodal status, and the differentiation of sub-epithelial
lesions.
Treatment depends on various factors, such as size, location and wheter
it is subephitelial or mucosally-based; endoscopic resection of duodenal
lesions provides a challenge due to certain anatomic characteristics of
the duodenum, such as a narrow lumen, a thin wall and a rich
vascularity, that result, respectively, in a higher rate of perforation
and bleeding. Endoscopic management involves cold snare polypectomy for
small lesions and endoscopic mucosal resection for larger
mucosally-based lesions located in the duodenum: this technique
consists, firstly, in a submucosal injection of sterile normal saline
(or a mixture of saline and epinephrine 1:100000) around and underneath
the lesion and successively in a hot-snare polipectomy3. EMR has been shown to be safe and effective in the
treatment of duodenal lesions, as reported in several studies, but it
can be associated to a substantial risk of complication, such as delayed
bleeding, perforation, especially in case of large (10-29 mm) or giant
(>30 mm) lesions, pancreatitis and stenosis4.
ESD is not recommended in the duodenum for the high rate of
complications, both for the thin duodenal wall and the rich vascularity.
In case of GISTs or other malignant lesions, they should be referred for
surgical resection after endoscopic diagnosis and laparoscopy has been
adopted with gradually increasing frequency in the management of these
lesions 3.
Gastric heterotopia consists on the presence of gastric tissue in a
place where is not normally found; the most common locations are the
esophagus and Meckel’s diverticulum but it may be found in all the
gastrointestinal tract 5.
Duodenal gastric heterotopia is a benign condition affecting from 0.5%
to 2% of the population and it can be classified into congenital or
acquired type.
The congenital type is likely due to an error in the differentiation of
the endoderm during embryogenesis and it was initially defined as an
elevated lesion of specialized oxyntic glands replacing the whole
thickness of the duodenal mucosa. Successively, it was proposed that
fundic-type mucosa could develop in the duodenum as a consequence of
metaplastic change induced by peptic injuries and, in particular, by
hypergastrinemia, as reported in patients with Zollinger Ellison
syndrome or in patients using proton-pump-inhibitor (PPI)6,7. On the basis of literature, we cannot certainly
say wheter the case of our patient is congenital or acquired; young age
favours congenital origin, although the continued use of PPI cannot
exclude acquired form. It’s important to differentiate gastric
heterotopia from gastric metaplasia, that is an acquired lesion
consisting on a change of one type of fully developed tissue to another
differentiated tissue, usually due to inflammatory conditions, where
there are no oxyntic glands 8.
Gastric heterotopia usually is an incidental finding and often it is
asymptomatic, or it may presented with dyspepsia, peptic ulcer symptoms,
gastrointestinal bleeding, perforation or, rarely with obstructive
symptoms. In most cases, the diagnosis of gastric heterotopia is
performed by histological examination and not during endoscopy, as in
this report. Agha et al. 5 described 17 cases of
heterotopic gastric mucosa in the duodenal bulb confirmed by
histological examination in 25 patients undergoing EGD; endoscopic
features were related to the radiographic findings of the lesion on
upper gastrointestinal barium studies and 68% of cases were described
as clusters of 1 to 3 mm plaques raised above the healthy duodenal
mucosa, and in 20% of cases as nodular mucosa with superficial
erosions. The most frequent location is duodenal bulb, where gastric
heterotopia is commonly found as multiple small polyps2: to the best of our knowledge, this is the first
report of a large polypoid gastric heterotopia in the third portion of
duodenum, removed endoscopically, in a young man. Data regarding gastric
heterotopia in the duodenum derive from small studies, mostly carried
out several years ago, and from rare case reports, and the clinical
significance, histopathological and functional characteristics remains
mostly unknown.
The therapeutic options for gastric heterotopia includes endoscopic or
surgical resection to prevent complications; the combination of clinical
presentation, endoscopic evaluation and radiologic imaging is useful in
making the diagnosis and guiding to the appropriate treatment8. The endoscopic management of duodenal lesions
remains challenging, because of the high risk of complications, such as
bleeding and perforation, due to the thin duodenal wall and the rich
vascularity; furthermore, the curved anatomical configuration of the
duodenum makes visualization and maintaining endoscope position
difficult. For this reason, in this case we performed an EMR under
laparoscopic vision in anticipation that it could be configured the
impossibility of endoscopic management, both for the resection of the
lesion and for the management of any complications requiring surgical
treatment.
Conflicts of Interest : The authors have no potential conflicts
of interest.
Funding: None.
Authors’ contribution: FM, AC: conceptualized and designed the
study, drafted the initial manuscript, and reviewed and revised the
manuscript. NG, MM, MM: conducted literature search on the topic,
contributed to writing of discussion and revised the manuscript. EG: led
histopathology interpretation of case and revised the manuscript. GA,
GDP: supervised work and revised the manuscript. All authors approved
the final manuscript as submitted and agree to be accountable for all
aspects of the work..
Acknowledgments : None to declare