CASE 13815 Published on 06.09.2016

Accessory spleen mimicking a pancreatic tumour


Abdominal imaging

Case Type

Clinical Cases


Alejandro Rodriguez1, Yanet Torres

(1) Jefe del servicio de Radiología
Clínica Ricardo Palma,
Av. Javier Prado Este 1066,
San Isidro, Lima 27, Perú

18 years, male

Area of Interest Abdomen ; Imaging Technique CT, MR
Clinical History
An 18-year-old male patient with sporadic abdominal pain.
Imaging Findings
CT demonstrated a mass in the pancreatic tail, the arterial phase showing a heterogeneous enhancing mass (arrow), the portal venous phase showing homogeneous enhancement (Fig. 1, 2).
On MRI the pancreatic mass showed a similar signal intensity to that of the adjacent normal spleen on all sequences (Fig. 3, 4).
Accessory spleen is a congenital abnormality that consist of foci of splenic tissue that are separate from the main body of the spleen [1]. Accessory spleens are seen in 10-30% of patients at autopsy [2].
The majority of cases are asymptomatic, so it is usually an incidental finding on imaging studies.
The second most common location in an autopsy study was the pancreatic tail (16.8%) [2].
It typically appears as a small and solid enhancing mass with a smooth, round or ovoid shape. The same as in a normal spleen, accessory spleens may demonstrate heterogeneous and serpiginous enhancement in the early CT phase because of the different rates of flow through the cords of the red and white pulp [3]. On venous phase CT it shows same pattern of contrast enhancement as the spleen.
On MRI the key for diagnosing accessory spleens is that their signal intensity is identical to those of the spleen on all the sequences including dynamic studies [4].
It is important to characterize accessory spleens to obviate unnecessary treatment or surgery.
Differential Diagnosis List
Intrapancreatic accessory spleen
Hypervascular pancreatic neoplasms
Hypervascular metastasis
Pancreatic islet cell tumour
Final Diagnosis
Intrapancreatic accessory spleen
Case information
DOI: 10.1594/EURORAD/CASE.13815
ISSN: 1563-4086