CASE 10843 Published on 19.03.2013

An infrequent pancreatic neoplasm in a young patient

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

Maria Inês Leite1, José Fonseca Santos1, Luísa Lobo1, António Alves2, Isabel Távora1

1- Radiology department of Hospital de Santa Maria, Lisbon, Portugal
2- Pathology department of Hospital de Santa Maria, Lisbon, Portugal
Patient

17 years, female

Categories
Area of Interest Abdomen ; Imaging Technique Ultrasound, MR, CT, Absorptiometry / Bone densiometry, Echocardiography
Clinical History
A 17-year-old female patient with African origin was referred to our hospital for diagnostic work-up of chronic anaemia. The laboratory tests only revealed an iron deficiency anaemia. No personal or familial history of pancreatic disease was known.
Imaging Findings
An abdominal ultrasonography (Fig 1) detected a previously unsuspected unilocular cyst in the pancreatic tail, presenting irregular wall thickening and measuring 4.5 cm in diameter.
Computed Tomography (CT) and Magnetic Resonance (MR) imaging studies were subsequently performed, given the worrisome features of the lesion.
The cyst wall showed early and homogeneous contrast enhancement on CT (Fig 2). Calcifications and septa were not evident within the tumour. Concomitant pancreatic and extrapancreatic lesions and peripancreatic tissue changes were also excluded.
The cyst locule presented low-signal intensity on T1WI MR sequences (Fig 3a) and high-signal intensity on T2WI MR sequences (Fig 3b), being suggestive of simple fluid. A communication between the cyst and the pancreatic duct was not seen at MR cholangiopancreatogram (MRCP; Fig 3c). There was only mild upstream ductal dilatation, probably due to mass effect, and the MR signal of the remaining pancreatic parenchyma was normal.
A surgical approach was advocated and a distal pancreatectomy was performed.
Discussion
Pancreatic neoplasms occur uncommonly in the paediatric age and to our knowledge, poorly differentiated neuroendocrine carcinomas have not been yet reported [1-3].
Pancreatic neuroendocrine neoplasms (NEN) are derived from endocrine lineage cells and express neuron-specific markers [1, 4]. They can be either functioning or nonfunctioning and are subdivided into well-differentiated (low- to intermediate-grade) neuroendocrine tumours (NETs) and poorly-differentiated (high-grade) neuroendocrine carcinomas (NECs) [5].
NENs are most commonly located in bronchopulmonary and gastrointestinal systems; 9.5% of them are found in the pancreas [6].
Their incidence has risen, mainly due to a higher diagnostic rate of nonfunctioning tumours that account for 50% of cases [3, 6].
NENs are most commonly functioning in the paediatric age, with insulinomas (47%) and gastrinomas (30%) being the most prevalent NETs subtypes [1]. The association with familial syndromes (multiple endocrine neoplasia type1, von Hippel-Lindau, neurofibromatosis type1, tuberous sclerosis) is higher in this age group [1, 3, 4].
Insulinomas and gastrinomas generally appear as small solid lesions with intense and homogeneous contrast enhancement [1]. Cystic changes, calcifications and necrosis can be present in larger lesions and usually carry a worse prognosis [3]. A hypervascular rim is a distinctive feature seen in more than 90% of cystic NENs [3]. The pancreatic NECs reported in older adults were located in the head and presented as large masses with multiple metastases [3].
In the paediatric work-up of a cystic pancreatic lesion, pseudocysts should be considered first, particularly in the presence of corroborative history and typical imaging findings. Otherwise, a neoplasm should be considered, with pancreatoblastomas and solid pseudopapillary tumours representing the most prevalent neoplasms [1, 3, 7, 8]. The former generally occurs in young children and presents as a multilocular mass with enhancing septa. Its large dimensions can pose a diagnostic problem when the pancreatic origin is not clearly defined [1]. The latter are predominantly seen in East Asian and African adolescents and usually present as mixed solid and cystic lesions. Haemorrhagic components and peripheral fibrous capsule are characteristic features [1, 7, 8]. Other uncommon paediatric malignant tumours of the pancreas include acinar cell and ductal adenocarcinomas, sarcomas, lymphomas and cystadenocarcinomas [1, 2]. Mucinous and serous cystadenomas have also been occasionally reported [1, 8].
The prognosis and the therapeutic approach of pancreatic NENs are still uncertain in children, given the limited number of cases described [2]. Surgical resection, combined with chemotherapy is now considered the mainstay treatment of these tumours, which are metastatic and locally invasive at presentation in 10% to 20% of cases [1-3].
Differential Diagnosis List
Poorly differentiated neuroendocrine carcinoma of the pancreas
Pseudocyst
Solid pseudopapillary tumour
Pancreatoblastoma
Other rare malignant neoplasms: acinar cell carcinoma
ductal adenocarcinomas
cystoadenocarcinomas
sarcoma
lymphoma
Final Diagnosis
Poorly differentiated neuroendocrine carcinoma of the pancreas
Case information
URL: https://www.eurorad.org/case/10843
DOI: 10.1594/EURORAD/CASE.10843
ISSN: 1563-4086