Lymphangiomas are benign vascular tumors arising from the lymphatic system . They account for about 5% of tumors in children and are commonly found in the head and neck region . Other sites reported in the literature include pleura, pericardium, groin, bones, liver, spleen, pancreas, colon, omentum, and genital organ .
Pancreatic lymphangioma is a very rare tumor accounting for less than 1% of abdominal lymphangioma and less than 0.5% of all cystic pancreatic lesion . These tumors result from lymphangiectasia as a consequence of a blockage of lymphatic flow. This may be associated with congenital malformations or obstructions as a result of an inflammatory process, radiotherapy, surgery, or any abdominal trauma . It is more common in the pediatrics population, which is similar in our case and has a slight female preponderance .
These tumor are benign in nature, slowly growing, and usually asymptomatic . Some patients present with abdominal pain and associated abdominal mass [6,7,8], as does our patient.
There are no associated laboratory findings specific to this abnormality. Abdominal imaging such as ultrasound and CT scan assist in the diagnosis and evaluation of such lesions; however, imaging by itself is not 100% specific to differentiate lymphangiomas from other cystic pancreatic lesions such as pseudocysts, cystadenomas, congenital cysts, and ductal carcinomas. Thus, this pathology can be differentiated from other cystic pancreatic lesions by histopathologic examination [3, 9, 10]. On abdominal ultrasound, the typical presentation of lymphangioma is multilocular lesion with homogeneous serous composition that appears anechoic. CT scan revealed a multiloculated cystic mass with fluid attenuation, thin septa within the lesion, and nonenhancing with no solid component or calcification seen. The tumor does not invade adjacent structures, which was similar to our patient’s CT scan.
Pathologically, lymphangioma can be classified as macrocystic, microcystic, or mixed-type lymphangioma. Macrocystic lymphangiomas are greater than 1 cm in diameter and occur in areas with loose connective tissue such as in the abdomen, neck, and axilla, while microcystic lymphangiomas are less than 1 cm in diameter and arise in areas with dense connective tissue such as tongue and lip. The natural history of lymphangioma depends on its histology type. Macrocystic and mixed types can spontaneously regress, while microcystic lymphangioma does not regress. Therefore macrocystic and mixed types can be serially followed in asymptomatic patients with stable tumor [6, 10].
Surgical interventions are reserved for patients with symptomatic pancreatic lymphangioma and for those with diagnostic dilemmas. Excision of the mass is considered to be curative. As there is a high chance of recurrence, the mass should be removed in its entirety [2, 3, 5]. We have also removed the mass as a whole in our case. Some patients might also require extensive pancreatic resections such as Whipple procedure or distal pancreatectomy depending on the size and location of the mass .