Intraductal papillary mucinous neoplasm of the oesophagus: an unusual case of dysphagia

Abstract

We report the case of a 58-year-old woman presenting with dysphagia secondary to an intraductal papillary mucinous neoplasm arising from a heterotopic pancreas in the oesophageal wall. This was successfully treated with a laparoscopic/thoracoscopic ivor Lewis oesophagectomy. Dysphagia is the most common symptom of oesophageal tumours regardless of aetiology of the tumour and can be treated successfully with surgical resection. Through an extensive search of the literature, we found that a heterotopic pancreas in the oesophagus is extremely rare with only ten cases being reported. We describe what we believe to be the first case of a heterotopic pancreas in the oesophagus transforming into an intraductal papillary mucinous neoplasm.

Dysphagia is the most common presenting symptom of oesophageal tumours. More than 99% of oesophageal tumours are adenocarcinomas or squamous cell carcinomas and less than 1% are gastrointestinal (GI) stromal tumours, carcinoid, leiomyosarcomas, malignant melanomas and lymphomas.¹ We report the first case of an intraductal papillary mucinous neoplasm (IPMN) of the oesophagus presenting with dysphagia.

Case history

A 58-year-old housewife presented with a history of progressive dysphagia over several months. She described no other symptoms and no weight loss. Her past medical history included mild asthma, recurrent epistaxis and a previous detached retina. She was on no regular medications and was a non-smoker. There was no significant finding on examination or routine blood tests.

At the referring hospital, she underwent two upper GI endoscopies identifying a 2.5–3cm irregular mass at the gastro-oesophageal junction but biopsies did not reveal the aetiology of the mass. Computed tomography showed some patchy changes in the right lower and right upper lobes of the lungs. However, when she attended for biopsy of these areas they had regressed and were diagnosed as infective changes. She also had positron emission tomography, which showed increased activity in a paraoesophageal mass and some mediastinal lymph nodes. The patient’s magnetic resonance imaging (Fig 1) was reported as evidence of nodular change in a hiatus hernia, no definable transmural infiltration or lymphadenopathy. The rest of the organs visualised including the pancreas were normal.

Figure 1.

Magnetic resonance imaging of mediastinum showing nodular change in mucosa of presumed hiatus hernia

A third upper GI endoscopy (Fig 2) with endoscopic ultrasonography demonstrated nodular friable mucosa at 35cm and 36cm in the left hemicircumference. In the centre there appeared to be a central crater from which mucus was exuding. There was no central ulceration or stenosis. The remainder of the oesophageal mucosa was normal. The endoscopic ultrasonography reported an almost exclusively extraluminal, 36mm x 28mm tumour situated between 35cm and 37cm in the left hemicircumference. The vast majority of the tumour appeared to comprise thick mucosal and submucosal layers, with clearly identifiable ‘frond-like’ projections. In between these there were small anechoic areas that probably represented mucus. Two reactive lymph nodes were seen in the subcarinal space but no mediastinal, perigastric or coeliac axis lymphadenopathy was identified.

Figure 2.

Upper gastrointestinal endoscopy showing extraluminal tumour exuding mucus

Figure 3.

Surgically resected oesophagus and stomach showing intraductal papillary mucinous neoplasm

Due to the extraluminal location of the mass, endoscopic removal was not deemed feasible and the patient was advised to have it surgically resected. The options were an oesophagogastrectomy or a local resection with a Merendino-type reconstruction. A laparoscopic/thoracoscopic Ivor Lewis oesophagectomy was performed (Fig 4). The postoperative recovery was unremarkable and at the patient’s three-month post-operative outpatient review she was in good health.

Histopathology of the specimen revealed an IPMN arising from a heterotopic pancreas in the oesophageal wall. The lesion was completely excised and all surgical margins were clear.

Discussion

Heterotopic pancreas was first described by Jean Schultz in 1729 and is defined as pancreatic tissue that lacks anatomic or vascular connection with the pancreas. The exact frequency of heterotopic pancreas is unknown but the literature reports it as being present in 0.55–13.7% of autopsies and seen at 0.2% of upper abdomen operations.² It can be found anywhere in the GI tract, with over 90% of cases involving the stomach, duodenum or jejunum. After an extensive literature search, it was found that only ten cases of heterotopic pancreas have been reported in the oesophagus.

IPMN was described initially by Ohashi et al in 1982.³ In 1996 the World Health Organization (WHO) established criteria to classify IPMNs and to distinguish them from other mucin producing cystic neoplasms.⁴ The WHO defines them as intraductal mucin producing neoplasms with tall, columnar, mucin containing epithelium with or without papillary projections.⁵ These neoplasms extensively involve the main pancreatic ducts and/or major side braches. They differ from mucinous neoplasms by lacking ovarian stroma. IP-MNs account for approximately 7% of clinically diagnosed pancreatic neoplasms.⁵

Cystic lesions in the pancreas are being detected more frequently due to increased use and sensitivity of non-invasive abdominal imaging. These lesions were previously thought to be benign but evidence has shown that up to 50% are neoplastic.⁵ On solely radiological appearance it is difficult to differentiate between benign and malignant lesions. This has led to the American College of Gastroenterology producing guidelines on the management of cystic lesions of the pancreas.⁶ A heterotopic pancreas functions physiologically and pathologically as an orthotopic pancreas. It can develop pancreatitis, cysts, pseudocysts, bleeding from ulceration, gastric outlet obstruction, intussusception and even malignant transformation. Recently, several case reports of a heterotopic pancreas with cystic changes have been published.⁷ It is possible that these were unrecognised IPMNs. It therefore correlates that cystic change in a heterotopic pancreas should be evaluated with the same care as in an orthotopic pancreas to avoid misdiagnosis of neoplastic change.

IPMNs have high malignant potential and transform from adenomas to invasive cancer similar to colonic polyps. The rate of progression to malignancy is thought to be slow, at approximately 15–20 years. Surgical resection, in suitable candidates, is the advised treatment.⁸ A study from 2010 reported a five-year survival rate of 77% for non-invasive IPMNs and 43% for IPMNs with associated invasive cancer following surgical resection.⁵

Conclusions

Dysphagia is the most common presenting feature of tumours of the oesophagus. Despite this being the only reported case of an IPMN arising from a heterotopic pancreas in the oesophageal wall, it was treated successfully with an oesophagectomy.