Indian Journal of Pathology and Microbiology

: 2010  |  Volume : 53  |  Issue : 3  |  Page : 581--582

Retroperitoneal fetiform teratoma

Sandhya Venkatachala, S Shanthakumari 
 Department of Pathology, PSG Institute of Medical Sciences and Research, Peelamedu, Coimbatore - 641 004, India

Correspondence Address:
Sandhya Venkatachala
PSG Institute of Medical Sciences and Research, Peelamedu, Coimbatore - 641 004

How to cite this article:
Venkatachala S, Shanthakumari S. Retroperitoneal fetiform teratoma.Indian J Pathol Microbiol 2010;53:581-582

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Venkatachala S, Shanthakumari S. Retroperitoneal fetiform teratoma. Indian J Pathol Microbiol [serial online] 2010 [cited 2021 Oct 28 ];53:581-582
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A female child of 3 months presented with abdominal distension. An abdominopelvic computerized tomography scan revealed a 10.5 cm x 9.4 cm x 8.8 cm-large cystic lesion with calcifications/bony elements scattered in it. However, a vertebral axis was not seen [Figure 1]. The mass occupied the right side of the retroperitoneum, pushing the right kidney inferiorly and superiorly, indenting the right lobe of the liver. The urinary bladder, uterus and ovaries were normal for the age. The preoperative radiological diagnosis was retroperitoneal teratoma. At laparotomy, the excised retroperitoneal mass was partly encapsulated, pale brown, globoid, measuring 9.0 cm Χ 8.0 cm Χ 6.0 cm and covered partially by hair- skin. At one end there was evidence of rudimentary limb formation with fused digits giving a fetiform appearance [Figure 1]. The cut surface was tan-white, soft and lobulated, with multiple islands of cartilage [Figure 2]. Bony elements with marrow and multiple cystic areas were also observed. There was no grossly recognizable ovary, fallopian tube, placenta or umbilical cord. Histopathological examination revealed a neoplasm partly covered by skin, with the underlying stroma showing pilosebaceous units. The stroma also showed mature adipose tissue, tubular glands lined by respiratory epithelium, seromucinous glands, mature glial tissue with choroid plexus, lymph node, eccrine glands, blood vessels, nerves, cartilage and bone with marrow. Solid areas with immature elements in the form of neuroepithelial rosettes, sheets of blastemal cells and immature cartilage were noted. The immature elements exceeded three low-power fields per slide in some of the sections, categorizing the teratoma as immature teratoma - grade III (Norris et al., three-tier grading system) [1] [Figure 2].

Teratomas are neoplasms composed of disorganized tissues derived from the germ cell layers. Rarely, these tumors develop a high degree of differentiation and organization resembling a malformed fetus. [2] The common extragonadal sites of teratoma are the sacrococcygeal region, mediastinum, retroperitoneum, head, neck, liver and stomach. Distinctive teratomas originating in the retroperitoneum were recognized by Morgagni and Benivieni in the 18 th century. The patients with retroperitoneal teratoma have ranged between newborn infants and individuals in the 6 th decade of life; majority under 17 months, with a higher female incidence. [3] Immature neuroectodermal tissues predominate in teratomas of this location, as was seen in this present case. In the present case, the excised retroperitoneal mass had a fetiform gross appearance. Wiess and others have reported a case of ovarian fetiform teratoma with no immature elements. [2] But, our case was unique in having immature neuroectodermal elements. A single case of such an entity has been reported by Saito et al.[4] A pathological condition that arises in the retroperitoneum and is structurally akin to fetiform teratomas is " fetus - in -fetu." Fetus - in - fetu is a rare congenital condition in which a vertebrate fetus is incorporated within its twin. Fetiform teratomas are chaotic aggregation of tissue structures lacking a vertebral or notochordal axis whereas fetus - in - fetu exhibit several organ systems and has an imperfect vertebral column that allows discernment of symmetry. [5] In children, the two most common retroperitoneal tumors are Wilms tumor and neuroblastoma. [6] It is also important to rule out a gonadal germ cell primary tumor. We report this case of immature retroperitoneal teratoma grade 3 for its unique presentation as fetiform mass with immature neuroectodermal elements.


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