An 83-year-old woman came to our institute with abdominal pain,
tomographic evidence of multiple pancreatic cystic lesions, and abnormal
thickening of the pyloroduodenal region. Magnetic resonance imaging showed
multiple cysts in the pancreatic body, isthmus, head, and uncinate process,
some with clear communication with the pancreatic duct ([Fig. 1]), and a parietal thickening of the duodenum
with contrast enhancement, in very close proximity to a cystic lesion in the
pancreatic isthmus ([Fig. 2 a]). Endoscopic
ultrasound (EUS) showed a multiloculated, septated cystic lesion in the
pancreatic isthmus, with a hypoechoic pericystic lesion invading the duodenal
bulb ([Fig. 2 b]). Gastroscopy confirmed a
villous lesion in the duodenal bulb, involving the inferoposterior wall ([Fig. 2 c]). EUS showed that the intraduodenal
lesion was heterogeneous with a solid-cystic aspect ([Fig. 2 d]). Biopsy of the duodenal lesion
confirmed duodenal wall invasion by a malignant intraductal papillary mucinous
neoplasm (IPMN) ([Fig. 2 e, f]).
Fig. 1 Magnetic resonance
cholangiopancreatography shows multiple cysts.
Fig. 2 a Magnetic resonance
imaging (MRI) showing the cystic lesion in the pancreatic isthmus, and parietal
thickening of the duodenal bulb wall (white arrow, duodenal lumen; red arrow,
pancreatic isthmus cyst; green arrow, intraduodenal lesion). b Endoscopic ultrasound (EUS) aspect of the cystic lesion in
the pancreatic isthmus. A hypoechoic pericystic lesion invades the duodenal
bulb wall, and there is interruption of the muscularis propria (white arrow,
duodenal lumen; yellow arrow, muscularis propria of the duodenal bulb wall; red
arrow, pancreatic isthmus cyst; green arrow, intraduodenal lesion).
c Duodenoscopic image of villous lesion in the duodenal
bulb (green arrow, intraduodenal lesion). d EUS aspect
of duodenal bulb lesion as a hypoechoic solid-cystic mass. (Green arrow,
intraduodenal lesion.) e Duodenal bulb lesion biopsy.
Histological examination shows submucosal invasion with incipient interruption
of muscularis mucosae by adenocarcinoma. Note the intact mucosa layer (green
arrow, intraduodenal lesion). f Box magnification
showing adenocarcinomatous component of malignant intraductal papillary
mucinous neoplasm (IPMN) (green arrow, intraduodenal lesion).
EUS fine-needle aspiration cytology of a pancreatic cyst in the
uncinate process showed atypical cells with severe dysplasia, strongly
suggestive of malignant IPMN ([Fig. 3]), as
previously reported [1].
Fig. 3 Fine-needle aspiration
(FNA) cytology of the pancreatic cyst in the uncinate process, showing a
cluster of atypical cells with severe dysplasia, very suggestive of
malignancy.
This report highlights a case of a degenerating multifocal IPMN
invading the duodenal bulb. Benign and malignant IPMNs can extend to
surrounding organs (duodenum, common bile duct, stomach) [2]
[3]
[4]
[5]. In benign lesions, mucus produced by tumor cells is
compressed and exerts pressure, inducing ischemia, atrophy, and disappearance
of the gastroduodenal or bile duct wall, with final penetration by the IPMN;
these lesions are called the “automatic type.” On the other hand,
malignant lesions can directly infiltrate surrounding organs and are called the
“invasive type” [2]
[3].
The intraluminal lesion of an invading IPMN can assume, at EUS, the
same solid-cystic pattern as the malignant pancreatic lesion. It is also worth
bearing in mind that there can be synchronous multifocal degeneration of IPMNs,
as evidenced in our case by the presence of a malignant pancreatic isthmus IPMN
invading the duodenal bulb, and a cytology-proven malignant IPMN in the
uncinate process. Both these aspects should be taken into consideration for
diagnostic purposes and therapeutic strategies.
Endoscopy_UCTN_Code_CCL_1AZ_2AB
