19 November 2009 Case of the Week #162


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Thanks to Dr. Atif Ahmed, Children's Mercy Hospitals and Clinics, Kansas, MO (USA), for contributing this case. This case was reviewed in May 2020 by Dr. Jennifer Bennett, University of Chicago and Dr. Carlos Parra-Herran, University of Toronto.


Case of the Week #162


Clinical History


A 9 month old girl was admitted for repair of an imperforate anus. Distal sacral agenesis was identified on X-ray. Imaging studies also revealed a partly cystic, partly solid mass in the presacral area.


Micro images:



What is your diagnosis?




























Currarino Syndrome, with components of mature cystic teratoma and ependymoma (anaplastic, WHO grade III)




The cystic areas were grossly and microscopically identified as mature cystic teratoma, composed of fibrous tissue, adipose tissue and glandular cystic elements including a dermoid cyst (fig 1). In addition, a neuronal tumor is present (figures 2 and 3) characterized by papillary formations, tumor cells arranged around islands of mucin, and other histologic features suggestive of myxopapillary ependymoma. The tumor cells stained diffusely with GFAP and vimentin. Further analysis revealed hypercellularity, increased mitotic rate and high MIB-1 proliferation rate (>50%), leading to reclassification of the tumor to anaplastic ependymoma (WHO grade III).


Currarino syndrome is a triad of (a) partial sacral agenesis with intact first sacral vertebra, (b) anorectal malformations and (c) a presacral mass (J Med Genet 2000;37:561). It is an autosomal dominant syndrome associated with mutations in the MNX1 (HLXB9) gene (J Pediatr Surg 2009;44:1892). Patients with the same mutation may have variable phenotypic expression (J Hum Genet 2007;52:698). Presacral tumors reported with this syndrome include anterior myelomeningocele, teratoma, hamartoma, dermoid cyst, neuroenteric cyst or a combination (Am J Med Genet 2004;128:299).


Teratoma and myelomeningocele are the most frequent presacral components. Teratomas may undergo malignant degeneration into peripheral primitive neuroectodermal tumor (Pediatr Blood Cancer 2008;50:172). The present case represents the first reported occurrence of ependymoma and teratoma in a patient with Currarino syndrome.


Additional references: Neurosurgery 2006;58:924, Childs Nerv Syst 2000;16:522, Pediatrics 2002;109:961



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