Epidermoid cyst arising from an intrapancreatic accessory spleen: A case report and review of the literature
- Authors:
- Published online on: December 4, 2012 https://doi.org/10.3892/ol.2012.1061
- Pages: 469-472
Abstract
Introduction
The occurrence of an accessory spleen is not rare; it affects approximately 10% of the general population, and 16% of all cases are intrapancreatic (1), However, the development of an epidermoid cyst of intrapancreatic accessory spleen (IPAS) is not common, with 30 cases (2–29) described in the literature since Davidson et al(2) described the first case of epidermoid cyst of IPAS. Due to the difficulty in differentiating the lesion from a cystic neoplasm of the pancreas by an imaging study (4), the majority have been diagnosed following surgical resection, with the exception of one case by Itano et al(5). Pre-operative diagnosis was mainly cystic neoplasm of the pancreas. Herein, we report a case of 54-year-old female with an epidermoid cyst of an IPAS and review the literature.
The study was approved by the ethics committee of Chosun University Hospital, Gwangju, Korea (IRB No.: CHOSUN 2012-10-007). The committee approved the waiver of patient consent for these cases.
Case report
A 54-year-old female with iron deficiency anemia was admitted to hospital complaining of dizziness and abdominal discomfort. During the clinical workup, a 2.3 cm-radiological-sized cystic mass was detected in the tail of the pancreas by abdominal computed tomography (CT; Fig. 1). Distal pancreatectomy was performed upon clinical diagnosis of pancreatic cancer. Grossly, the surgical specimen showed a well-demarcated multilocular cystic mass within the pancreatic parenchyma, measuring 2.0×1.5 cm (histoligcal size) and containing dark serosanginous fluid. Microscopic investigation revealed that the majority of the epithelial lining was comprised of multilayered cuboidal epithelium with focal denudation. However, no atypical or malignant changes were observed (Fig. 2). Immunohistochemical staining demonstrated that the epithelial lining was reactive for cytokeratin (CK) and CK7. The cystic wall demonstrated histologically normal splenic pulp tissue, which was surrounded by a hyalinized fibrous band. The final pathologic diagnosis was an epidermoid cyst arising from an IPAS. The six-month post-operative course was uneventful.
Discussion
Approximately 16% of accessory spleens occur in or around the tail of the pancreas (1). An epidermoid cyst in an IPAS is extremely rare and was first described in 1980 by Davidson et al(2). Following this, 30 cases of epidermoid cyst of IPAS have been described in the literature. Table I summarizes the 31 cases of epidermoid cyst in an IPAS, including the case we describe here. The cases involved 15 males and 16 females, with ages ranging from 12–70 years (mean, 46 years). All cysts were located in the pancreatic tail. While 16 patients were asymptomatic, various symptoms were observed in 14 patients, including weight loss, nausea, vomiting, abdominal pain and discomfort, back pain, epigastric pain and fever. Histological analysis revealed that the cysts were solitary or multilocular, lined with keratinized or non-keratinized stratified squamous epithelium or cuboidal epithelium, and in some cases exhibiting mixed-form epithelium.
Table I.Summary of the 31 cases of epidermoid cyst arising in intrapancreatic accessory spleen (IPAS), including the present case. |
An elevation of serum CA 19-9 level was observed in 10 cases, hence the difficulty in pre-operatively differentiating between an epidermoid cyst in an IPAS and pancreatic malignancy during clinical analysis. Higaki et al(9) revealed that the serum CA 19-9 level markedly decreased to within the normal range following surgery in a patient diagnosed with an epidermoid cyst in an IPAS, suggesting that the serum CA 19-9 originated in the epidermoid cyst in an IPAS.
The histogenesis of an epidermoid cyst in an IPAS may be identical to that of a splenic epidermoid cyst (23). There are three hypotheses concerning the histogenesis of an epidermoid cyst in an IPAS (10). Firstly, the cyst may originate from mesothelial inclusion with subsequent squamous metaplasa (30). Secondly, teratomatous derivation or an inclusion of fetal squamous epithelium may cause cystic change (31). Thirdly, a derivation from the pancreatic duct may protrude into the accessory spleen (10). In a case described by Kadota et al(23), there were pancreatic ducts in the fibrous tissue surrounding the accessory spleen tissue, and the squamous and cuboidal epithelia indicated a transitional appearance from one form to the other. Additionally, immunohistochemical analysis demonstrated that the staining results of the cystic epithelial lining were identical to those of the pancreatic duct. These results support the third hypothesis.
A pre-operative imaging diagnosis of an epidermoid cyst in an IPAS is extremely difficult. Notably, a diagnosis of abdominal CT in the present case was also pancreatic tail cancer. As there are no characteristic features to define the lesion on radiology, it is not possible to entirely differentiate the cystic pancreatic malignancy prior to surgery and histopathological examination (28).
In conclusion, an epidermoid cyst in an IPAS is an extremely rare disease entity, and radiographic and clinical results (including CA 19-9 elevation) are similar to those of other cystic pancreatic neoplasms. As a result, the possibilty of such a cystic lesion should be considered in the differential diagnosis of a pancreatic cystic lesion.
Acknowledgements
This study was supported by research funds from Chosun University, 2010.
References
Halpert B and Alden ZA: Accessory spleens in or at the tail of the pancreas. A survey of 2700 additional necropsies. Arch Pathol. 77:652–654. 1964.PubMed/NCBI | |
Davidson ED, Campbell WG and Hersh T: Epidermoid splenic cyst occurring in an intrapancreatic accessory spleen. Dig Dis Sci. 25:964–967. 1980. View Article : Google Scholar : PubMed/NCBI | |
Hanada M, Kimura M, Kitada M, et al: Epidermoid cyst of accessory spleen. Acta Pathol Jpn. 31:863–871. 1981.PubMed/NCBI | |
Jibu T, Nagai H, Senba D, Wada Y, Kuroda A, Morioka Y, et al: A case of epidermoid cyst occurring in an intrapancreatic accessory spleen. Nihon Shokakibyo Gakkai Zasshi. 84:1859–1862. 1987.(In Japanese). | |
Morohoshi T, Hamamoto T, Kunimura T, et al: Epidermoid cyst derived from an accessory spleen in the pancreas. A case report with literature survey. Acta Pathol Jpn. 41:916–921. 1991.PubMed/NCBI | |
Nakae Y, Hayakawa T, Kondo T, et al: Epidermoid cyst occurring in a pancreatic accessory spleen. J Clin Gastroenterol. 13:362–364. 1991. View Article : Google Scholar : PubMed/NCBI | |
Tang X, Tanaka Y and Tsutsumi Y: Epithelial inclusion cysts in an intrapancreatic accessory spleen. Pathol Int. 44:652–654. 1994. View Article : Google Scholar : PubMed/NCBI | |
Furukawa H, Kosuge T, Kanai Y, et al: Epidermoid cyst in an intrapancreatic accessory spleen: CT and pathologic findings. Am J Roentgenol. 171:2711998. View Article : Google Scholar : PubMed/NCBI | |
Higaki K, Jimi A, Watanabe J, et al: Epidermoid cyst of the spleen with CA19-9 or carcinoembryonic antigen productions: report of three cases. Am J Surg Pathol. 22:704–708. 1998. View Article : Google Scholar : PubMed/NCBI | |
Tateyama H, Tada T, Murase T, et al: Lymphoepithelial cyst and epidermoid cyst of the accessory spleen in the pancreas. Mod Pathol. 11:1171–1177. 1998.PubMed/NCBI | |
Sasou S, Nakamura S and Inomata M: Epithelial splenic cysts in an intrapancreatic accessory spleen and spleen. Pathol Int. 49:1078–1083. 1999. View Article : Google Scholar : PubMed/NCBI | |
Tsutsumi S, Kojima T, Fukai Y, et al: Epidermoid cyst of an intrapancreatic accessory spleen: a case report. Hepatogastroenterology. 47:1462–1464. 2000.PubMed/NCBI | |
Choi SK, Ahn SI, Hong KC, Kim SJ, Kim TS, Woo ZH, et al: A case of epidermoid cyst of the intrapancreatic accessory spleen. J Korean Med Sci. 15:589–592. 2000. View Article : Google Scholar : PubMed/NCBI | |
Horibe Y, Murakami M, Yamao K, et al: Epithelial inclusion cyst (epidermoid cyst) formation with epithelioid cell granuloma in an intrapancreatic accessory spleen. Pathol Int. 51:50–54. 2001. View Article : Google Scholar : PubMed/NCBI | |
Sonomura T, Kataoka T, Chikugo T, et al: Epidermoid cyst originating from an intrapancreatic accessory spleen. Abdom Imaging. 27:560–562. 2002. View Article : Google Scholar : PubMed/NCBI | |
Yokomizo H, Hifumi M, Yamane T, et al: Epidermoid cyst of an accessory spleen at the pancreatic tail: diagnostic value of MRI. Abdom Imaging. 27:557–559. 2002. View Article : Google Scholar : PubMed/NCBI | |
Fink AM, Kulkarni S, Crowley P, et al: Epidermoid cyst in a pancreatic accessory spleen mimicking an infected abdominal cyst in a child. Am J Roentgenol. 179:206–208. 2002. View Article : Google Scholar : PubMed/NCBI | |
Kanazawa H, Kamiya J, Nagino M, et al: Epidermoid cyst in an intrapancreatic accessory spleen: a case report. J Hepatobiliary Pancreat Surg. 11:61–63. 2004. View Article : Google Scholar : PubMed/NCBI | |
Ru K, Kalra A and Ucci A: Epidermoid cyst of intrapancreatic accessory spleen. Dig Dis Sci. 52:1229–1232. 2007. View Article : Google Scholar : PubMed/NCBI | |
Itano O, Shiraga N, Kouta E, et al: Epidermoid cyst originating from an intrapancreatic accessory spleen. J Hepatobiliary Pancreat Surg. 15:436–439. 2008. View Article : Google Scholar : PubMed/NCBI | |
Servais EL, Sarkaria IS, Solomon GJ, et al: Giant epidermoid cyst within an intrapancreatic accessory spleen mimicking a cystic neoplasm of the pancreas: case report and review of the literature. Pancreas. 36:98–100. 2008. View Article : Google Scholar : PubMed/NCBI | |
Gleeson FC, Kendrick ML, Chari ST, et al: Epidermoid accessory splenic cyst masquerading as a pancreatic mucinous cystic neoplasm. Endoscopy. 40:E141–E142. 2008. View Article : Google Scholar : PubMed/NCBI | |
Kadota K, Kushida Y, Miyai Y, et al: Epidermoid cyst in an intrapancreatic accessory spleen: three case reports and review of the literatures. Pathol Oncol Res. 16:435–442. 2010. View Article : Google Scholar : PubMed/NCBI | |
Zhang Z and Wang JC: An epithelial splenic cyst in an intrapancreatic accessory spleen. A case report. JOP. 10:664–666. 2009.PubMed/NCBI | |
Itano O, Chiba N, Wada T, et al: Laparoscopic resection of an epidermoid cyst originating from an intrapancreatic accessory spleen: report of a case. Surg Today. 40:72–75. 2010. View Article : Google Scholar : PubMed/NCBI | |
Iwasaki Y, Tagaya N, Nakagawa A, Kita J, Imura J, Fujimori T, et al: Laparoscopic resection of epidermoid cyst arising from an intrapancreatic accessory spleen: a case report with a review of the literature. Surg Laparosc Endosc Percutan Tech. 21:e275–279. 2011. View Article : Google Scholar : PubMed/NCBI | |
Yamanishi H, Kumagi T, Yokota T, Koizumi M, Azemoto N, Watanabe J, et al: Epithelial cyst arising in an intrapancreatic accessory spleen: a diagnostic dilemma. Intern Med. 50:1947–1952. 2011. View Article : Google Scholar : PubMed/NCBI | |
Horn AJ and Lele SM: Epidermoid cyst occurring within an intrapancreatic accessory spleen. A case report and review of the literature. JOP. 12:279–282. 2011.PubMed/NCBI | |
Khashab MA, Canto MI, Singh VK, Hruban RH, Makary MA and Giday S: Endosonographic and elastographic features of a rare epidermoid cyst of an intrapancreatic accessory spleen. Endoscopy. 43:e193–194. 2011. View Article : Google Scholar : PubMed/NCBI | |
Ough YD, Nash HR and Wood DA: Mesothelial cysts of the spleen with squamous metaplasia. AM J Clin Pathol. 76:666–669. 1981.PubMed/NCBI | |
Lifschitz-Mercer B, Open M, Kushnir I and Czernobilsky B: Epidermpid cyst of the spleen:a cytokeratin profile with comparison to other squamous epithelia. Virchows Arch. 424:213–216. 1994. View Article : Google Scholar : PubMed/NCBI |