primary cysts have a lined epithelium and secondary cyst could be secondary to trauma . epidermoid splenic cysts are example of primary congenital cysts that contain an epithelial lining , unlike secondary cysts , which are composed of fibrous tissues ,
when the cyst is large they have nonspecific abdominal symptoms like pain , nausea , or a palpable mass usually in the left upper quadrant .
epidermoid cysts and parasitic cysts are examples of primary cysts and usually have a classic presentation on imaging . despite imaging modalities and the patient s history , it can be difficult to diagnose an epidermoid cyst without a histological examination .
the purpose of this paper is to discuss variable and atypical radiological presentation of primary splenic cysts including epidermoid cysts .
a 51-year - old female presented to the ed using private transportation with complaints of left upper quadrant abdominal pain , nausea and vomiting for a couple days .
she had significant medical history of hypertension , gerd , and hyperlipidemia with a bmi of 37.5 and no previous surgical history .
patient had quit smoking cigarettes two years prior , does not drink alcohol or use any illicit drugs .
physical exam was significant to being mildly tender to palpation over her left upper quadrant .
vitals , complete blood count , basic metabolic panel , liver function tests , and urine analysis were all within normal limits . abdominal ultrasound ( fig .
1 ) visualized a 7.7  cm complex mass in the medial aspect of the spleen .
2 ) revealed a hypodense cystic mass in the medial aspect of the spleen measuring 10.4  cm    8.2  cm with a hounsfield attenuation of 15 ; containing multiple foci of fat with hounsfield attenuation of 102 .
patient was assumed to have a confined cystic tumor of unknown etiology without any acute complications at this point .
after long discussion with the patient with this large cystic mass of the spleen of unknown pathology , splenectomy was offered to the patient .
she underwent uneventful laparoscopic hand - assisted splenectomy 6 weeks after presentation to the ed .
she continued to have an uneventful recovery on follow - up with no recurrence of painful symptoms .
4 ) , it weighed 404  g , and was 17    11    5  cm in dimensions and was partially cystic .
11    10    7  cm smooth walled yellow tan cyst was present . on microscopic examination , sections demonstrated unremarkable splenic parenchyma and cyst walls lined by stratified squamous epithelium .
immunohistochemical stains demonstrated an adequate distribution of cd20 + b - lymphocytes and cd3 + t - lymphocytes .
. examples of primary benign neoplasms involving the spleen include haemangiomas , lymphangiomas , angiomas and splenic mesenchymal tumors such as lipomas , angiomyolipomas , fibromas , fibrosarcomas , and leiomyosarcomas .
. they could be a pseudocyst secondary to trauma or a true cyst , which might be infectious or congenital such as an epidermoid cyst .
epidermoid splenic cysts are primary congenital cysts that contain an epithelial lining , unlike secondary cysts which are composed of fibrous tissues , .
patients usually do not present with specific symptoms if the cyst is small , and when the cyst is large , they have nonspecific abdominal symptoms like pain , nausea , or a palpable mass usually in the left upper quadrant . on imaging , epidermoid and parasitic cysts , which are also primary cysts , can be similar in appearance showing up as well - defined solitary lesions with septations . on computed tomography , septations , calcifications and internal debris
. when findings are consistent with multiple neighboring cysts or daughter cysts , parasitic cysts are in favor as a diagnosis .
epidermoid cysts of the spleen usually have a thin - walled anechoic appearance on ultrasound with no evidence of calcification on computed tomography . on t2-weighted magnetic resonance imaging ,
the cyst is hyper - intense , and on t1-weighted imaging , it is hypo - intense but can be increased depending on cyst contents .
we used computed tomography to accurately identify the location , size , and adjacent structures of the cyst with an understanding that a definitive diagnosis would only be made by histopathological examination .
we identified a complex mass on ultrasound and a hypodense lesion on computed tomography with multiple foci of fat , which were very different demonstrations from what is expected of a classic epidermoid or parasitic cyst on imaging . when examined , an epidermoid cyst usually has a white or grey smooth internal wall with fibrous trabeculations . under microscopic examination
, an epithelium is visualized that is stratified squamous , which was consistent with our findings , and the contents can be serous , turbid , or thick and vary in color .
surgical treatment is recommended for a symptomatic splenic cyst and for cysts larger than 5  cm , , .
marsupialization or fenestration as treatments are indicated for superficial cysts , but they have a high recurrence rate , . in our case a large cyst , greater than 5  cm was identified and extended behind the stomach and into the medial aspect of the spleen .
a total splenectomy was our indicated diagnostic and treatment of choice due to size of the cyst , presentation with symptoms , and also as a preventative intervention against future rupture , hemorrhage , infection , or recurrence .
it is important to recognize that epidermoid splenic cysts may not always present in a classic fashion on imaging so it is trivial to include them as a differential diagnosis when warranted .
the exact nature of a cyst will not be known prior to histological examination as in our case when imaging is not accurate or definitive in differentiation .
therefore , the cyst was treated based on symptomology , size , and location and a total splenectomy which was indicated , was performed .
bilal kharbutli , md and sharmilee vuyyuru , do have contributed in the study concept and writing .
 highlightssplenic tumors are not common , many can have minimal to no symptoms , and they can be found incidentally.splenic tumors can be primary or metastatic 
 . they can be benign or malignant.splenic cysts can be infectious , traumatic or congenital.epidermoid splenic cysts may not always present in a classic fashion on imaging , making diagnosis challenging.many splenic masses and complex cysts would require surgical pathological diagnosis . 
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