Unusual Cause of Abdominal Pain

Abstract

Question: A 24-year-old man visited our gastroenterology clinic due to intermittent, dull, left upper abdominal pain for 6 months. He had an unremarkable medical history and no history of abdominal trauma or surgery. He denied any weight loss. Physical examination revealed a palpable mass in the left upper abdomen. Laboratory examinations were within normal limits. Abdominal computed tomography (CT) and magnetic resonance imaging (MRI) were subsequently performed to clarify the nature of the lesion (Figures A and B). What are the findings of the abdominal CT and what is the diagnosis? Look on page 1609 for the answer and see the Gastroenterology web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI. Abdominal CT revealed a large, cystic lesion of the spleen with partial calcification of the wall (Figure A, arrow). T2WI MRI revealed a 14-cm, homogeneous, hyperintense, cystic lesion without contrast enhancement. The patient underwent laparoscopic splenectomy for the symptomatic tumor (Figure C). On histologic examination, the splenic cyst was lined by mature squamous cells and walled by fibrotic tissues with inflammation (Figure D). A diagnosis of splenic epidermoid cyst was made. Cystic lesions of the spleen are uncommon.1Chen Y.Y. Shyr Y.M. Wang S.E. Epidermoid cyst of the spleen.J Gastrointest Surg. 2013; 17: 555-561Crossref PubMed Scopus (18) Google Scholar, 2Dan D. Bascombe N. Harnanan D. et al.Laparoscopic management of a massive splenic cyst.Asian J Surg. 2010; 33: 103-106Abstract Full Text PDF PubMed Scopus (20) Google Scholar, 3Fan H. Zhang D. Zhao X. et al.Laparoscopic partial splenectomy for large splenic epidermoid cyst.Chin Med J (Engl). 2011; 124: 1751-1753PubMed Google Scholar Acquired splenic cysts are caused by trauma, pancreatitis, parasite infection, or neoplasm. Congenital splenic and epidermoid cysts are rare, comprising <10% of all nonparasitic splenic cysts; only 78 cases were reported in a recent review from 1950 to 2012.1Chen Y.Y. Shyr Y.M. Wang S.E. Epidermoid cyst of the spleen.J Gastrointest Surg. 2013; 17: 555-561Crossref PubMed Scopus (18) Google Scholar Epidermoid cysts are lined by keratinizing and nonkeratinizing epithelium that may be squamous or cuboidal.1Chen Y.Y. Shyr Y.M. Wang S.E. Epidermoid cyst of the spleen.J Gastrointest Surg. 2013; 17: 555-561Crossref PubMed Scopus (18) Google Scholar The etiology is believed to be congenital and proposed as mesothelial inclusion with squamous metaplasia and fetal squamous epithelium in the cyst or metaplasia in the cells lining the splenic sinus. Patients with splenic epidermoid cysts usually present with cysts at a young age, with a median age of 19 years; there is a slight female predominance. The most common symptoms presented are left upper abdominal pain or a palpable mass. In patients with splenic epidermoid cysts, 90% are uniloculated and uncomplicated. Complications from cysts are uncommon, but can include infection (6.8%), rupture (9.8%), or bleeding (2.7%).1Chen Y.Y. Shyr Y.M. Wang S.E. Epidermoid cyst of the spleen.J Gastrointest Surg. 2013; 17: 555-561Crossref PubMed Scopus (18) Google Scholar On imaging studies, uncomplicated cysts are a solitary, well-defined cystic lesion, occasionally with plaque-like wall calcification. The treatment for symptomatic cysts is open or laparoscopic splenectomy.2Dan D. Bascombe N. Harnanan D. et al.Laparoscopic management of a massive splenic cyst.Asian J Surg. 2010; 33: 103-106Abstract Full Text PDF PubMed Scopus (20) Google Scholar, 3Fan H. Zhang D. Zhao X. et al.Laparoscopic partial splenectomy for large splenic epidermoid cyst.Chin Med J (Engl). 2011; 124: 1751-1753PubMed Google Scholar Conservative therapy, such as aspiration or sclerotherapy, is associated with a high recurrence rate and a risk of bleeding or infection; it is therefore not recommended.