Fetiform Teratoma Research Articles

Demystifying Fetus-in-fetu: A Systematic Review of Its Clinical and Pathological Attributes.

Fetus-in-fetu (FIF) is an exceedingly rare condition, characterized by a fetal-like or fetiform mass with a calcified vertebral axis surrounded by other organs or limbs. This systematic review was conducted to comprehensively analyze the clinicopathological attributes, management strategies, and prognosis of FIF to consolidate existing knowledge on FIF. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a comprehensive search was performed across various electronic databases, using the keywords "fetus-in-fetu," "fetus-ex-fetus," "homunculus," or "fetiform teratoma" to look for published articles until December 2023. Data extraction and analysis were carried out for cases meeting the defined criteria for FIF diagnosis, that is "presence of both/either the vertebral column and/or long bones of extremities" and "absence of immature elements." A total of 249 case reports/case series comprising 241 single FIF cases and 33 multiple FIF cases were included for analysis. The majority of single FIF cases presented within the 1st year of life, with a slight male predominance. Retroperitoneal location was most common, and imaging modalities played a crucial role in preoperative diagnosis. Complete surgical removal of the mass with detailed histopathological examination is the cornerstone of treatment for FIF, with favorable outcomes in the majority of cases. Both mature and immature teratoma can rarely be found in association with FIF. This comprehensive systematic review enhances understanding of FIF, emphasizing the importance of accurate diagnosis by diligent histopathological examination, appropriate management, and vigilant postoperative monitoring for favorable outcomes.

Retroperitoneal homunculus lesion in a newborn male

Fetiform teratoma is a rare form of teratoma that resembles a malformed fetus due to highly organized differentiation. Most commonly seen arising from ovaries; however, we present a case of fetiform teratoma in the retroperitoneum in a male fetus. It is a unique case, as age, gender, and location point toward fetus-in-fetu where malignant transformation is highly unlikely. Distinction from fetus-in-fetu is necessitated due to malignant transformation in case of the presence of immature elements within.

Retained Foetus-in-Fetu or Fetiform Teratoma – A Diagnostic Dilemma and Operative Challenge

Abstract Foetus-in-fetu (FIF) is a condition where one of the twin foetuses is found developing inside the other. Differentiating this condition from fetiform teratoma (FT), in which the teratoma becomes highly differentiated to take a foetus-like appearance, often becomes arduous. Unfamiliarity with the situation and the presence of bone and hair within such lesions can potentially mislead the surgeon to diagnose it as a dermoid cyst erroneously. Suboptimal surgery can complicate things further when it comes to redoing operations and the final histopathological reporting. We report this case of a partially removed cystic retroperitoneal mass in a 14-year-old male, posing a significant surgical challenge due to dense adhesions to the vital retroperitoneal structures, such as common iliac vessels and ureter. We also faced similar diagnostic dilemmas during histopathology due to the tissues removed during the previous surgery. Based on gross and microscopic features, the possibility of a FIF or FT was rendered.

Fetiform Teratoma (Homunculus) Coexist with Intrauterine Foetus: A Case Report

Fetiform teratoma is also known as a homunculus, a rare form of mature cystic teratoma with a good prognosis. We report a case of fetiform teratoma that coexist with a female neonate in a 27-year-old woman. She presented with 2 days history of abdominal pain and generalized body weakness of 3 days at 38 weeks gestation. On clinical examination, gravid enlarged uterus with twin foetus palpated on a transverse lie and imminent foetal distress. Emergency Ultrasound done showed twin gestation at 39 weeks +5 days. The patient underwent an emergency caesarean section delivered of a female baby with a foetus like mass attached to the palate of the live female baby by a stalk. The clinical diagnosis of parasitic twin gestation was made and the mass was sent for histopathological analysis. On gross examination, a skin bearing mass with 2 limbs buds reminiscent of homunculus without demonstrable vertebrae or bony tissue on cross-section. Histopathology analysis showed tumour tissue composed of haphazard arrangement mature tissue comprising derivative from ectoderm namely skin tissue, sebaceous gland, hair follicle, mesodermal derivative are cartilage and adipose tissue. Endodermal differentiation is intestinal glands lined by columnar epithelial cells admixed with goblets cells. In summary, a diagnosis of fetiform teratoma was made and the baby that coexisted with the mass was adequately follow-up without any complications.

Differential diagnosis of a calcified cyst found in an 18th century female burial site at St. Nicholas Church cemetery (Libkovice, Czechia).

During archaeological excavations in burial sites, sometimes stoned organic objects are found, in addition to human remains. Those objects might be of a different origin, depending on various factors influencing members of a community (i.e. diseases, trauma), which provides information about their living conditions. The St. Nicholas Church archaeological site (Libkovice, Czechia) in the 18th century horizon of the cemetery, yielded a maturus-senilis female skeleton with a stone object in the left iliac fossa. This object was an oviform cyst-like rough structure, measuring 54 mm in length, 35 mm in maximum diameter and 0.2-0.7 mm shell thickness. Within the object there were small fetal bones (long bones, i.e. femur and two tibias, two scapulas, three ribs, vertebrae and other tiny bone fragments). Methods utilized to analyze the outer and inner surface morphology of the cyst and its inside, included: X-ray, CT imaging, SEM, histological staining and EDS. The EDS analysis revealed the presence of primarily oxygen, calcium and phosphorus in bone samples, and oxygen and silicon, in stone shell. Based on the length of the femur (20.2 mm) and tibia (16 mm) shafts, the fetal age was determined as being in the 15-18 week of pregnancy. The differential diagnosis was conducted, including for the three most probable cases: fetiform teratoma (FT), fetus-in-fetu (FIF) and lithopedion. The possibility of fetiform teratoma was discounted due to the presence of an anatomically correct spine, long bones and the proportions of the find. Although the low calcium content in the shell (2.3% atom mass), the lack of skull bones and the better developed lower limbs indicate fetus-in-fetu rather than lithopedion, the analyses results are unable to conclusively identify the object under one of these two categories since there are insufficient such cases in excavation material with which to draw comparison.

Retroperitoneal fetiform teratoma in an infant

Fetus in fetu is a rare intra-abdominal mass secondary to abnormal embryogenesis in a diamniotic monochorionic pregnancy. Teratoma, unlike fetus in fetu, does not show the vertebral axis or regional distribution of the organs. We report a 9-month-old male infant who presented with a large abdominal lump. The retroperitoneal mass was excised. On opening the sac, well-formed fetus-like structure was seen. The mass was connected to a yolk sac-like structure. The mass had the rudimentary head, thorax, abdomen, and finger-like buds giving a fetiform appearance but without vertebral column. Histopathological examination confirmed fetiform teratoma. The outcome was favorable.

Fetus in fetu or fetiform teratoma? Report of two cases

Fetus in fetu is a rare congenital entity in which a deformed parasitic twin develops within the body of a living newborn or a child. Meanwhile, fetiform teratoma is a rare congenital disorder with high degree of organoid differentiation resembling fetus in fetu. We present two cases of the rare entities with two unusual locations. A 1-week-old baby boy with a large anterior abdominal mass underwent CT-scan. A large mass containing pelvic bones, femora, tibia, fibula, fused kidneys, urinary bladder, hepatic parenchyma, brain tissue and spinal cord was noted in the anterior abdominal wall. The liver parenchyma of the host twin was fused with the hepatic parenchyma of the parasitic twin. Another 6-month-old baby girl with a large lumbar lump underwent ultrasonography, CT-scan and surgery. On imaging, a sac-like structure was noted in the lumbar region containing bowel segments, mesentery-like structure and few lymph nodes. Both cases are rare congenital anomalies and are a diagnostic challenge. It has been described that the presence of axial skeleton and limb buds differentiates the fetus in fetu from the fetiform teratoma, therefor, the first case was diagnosed as fetus in fetu and the latter one as fetiform teratoma.

Let's face it - 13 unusual causes of facial masses in children.

Facial swelling is commonly encountered in paediatric patients and is typically related to an underlying infection. The spectrum of possible causes, however, is wide, and includes traumatic, inflammatory, nutritional and neoplastic aetiologies. In this pictorial essay we present 13 examples of rare conditions selected from a total of 136 MRI examinations performed at our institution between April 2007 and May 2013. These include HIV-associated malignancies such as a case of plasmablastic lymphoma, parotid gland tumours including a parotid hamartoma, rare congenital lesions such as a thyroid fetiform teratoma, and infective lesions including tuberculosis of the mandible. In many cases, only minimal information could be gleaned from the literature, particularly with regard to imaging findings. An analysis of the spectrum of masses and specific clinical presentations allowed for the construction of a diagnostic flowchart which may serve to assist in unusual cases.Teaching Points• Facial swelling is commonly encountered in paediatrics, with a wide spectrum of possible aetiologies.• MRI is the favoured imaging modality for accurate assessment.• Facial swelling is typically infectious in nature, but includes various benign and malignant causes.• This pictorial essay presents 13 examples of rare conditions with corresponding imaging.

Sacrococcygeal Fetiform Teratoma Altman Type 1: A Rare Case Report in a 11 Year Old Girl

Fetiform teratoma (homunculus) is a rare but distinct entity, characterized by presence of more organoid differentiation than the classical teratoma but not enough to classify as fetus-in-fetu. Presence of rudimentary limbs in presence/absence of axial skeleton is often reported as an important differentiating feature. Sacrococcygeal location has been reported in a few case reports but in neonates only. This is a rare case of sacrococcygeal fetiform teratoma (Altman type 1) in an 11-year-old girl presenting as a gluteal mass.

Highly differentiated sacrococcygeal teratoma.

Sacrococcygeal teratoma is a well known entity and both its diagnosis and management have been thoroughfully described. Special mention deserves the highly differentiated teratoma as it presents complex organized tissular structures making it slightly different from the classic teratoma although it does not reach the defining characteristics of fetus-in-fetu.A female newborn without prenatal diagnosis presented sacro-coccygeal mass. X-ray image showed bone structures resembling tibia and fibula within the mass. She undertook surgery two days after delivery. Macroscopically, the mass showed besides the bones described on X ray image, cartilaginous structures, some loops of bowel and tissue resembling a finger. There were also some cystic areas. Highly differentiated teratoma also called fetiform teratoma seems to be a defined entity apart from the classical sacrococcygeal teratoma and the fetus-in-fetus. However differences regarding physiopathological and clinical aspects have not been yet completely described.

Intracecal fetiform teratoma

Fetiform teratoma is a rare form of mature cystic teratoma that is highly developed and organized, resembling a fetus-like structure. These are rare entities that have been typically described in women of reproductive age and most often present as ovarian masses. Only two cases of a fetiform teratoma have been reported in a male. Although teratomas are a common benign entity, only five prior cases of teratoma involving the cecum have been described. We present an atypical case of an intracecal fetiform teratoma occurring in a 2(1/2)-year-old Chinese boy.

Malignant Transformation of a Well-organized Sacrococcygeal Fetiform Teratoma in a Newborn Male

We report herein a case of a male newborn with a sacrococcygeal fetiform teratoma (FT). The baby presented with a large coccygeal teratoma. The preoperative diagnosis of FT was made by plain radiography, ultrasonography and magnetic resonance imaging. The baby was successfully treated by complete excision and pelvic floor reconstruction. Postoperative follow-up was uneventful until the teratoma recurred 11 months later as a malignancy. After undergoing a second operative procedure accompanied by chemotherapy, he has been doing well for 18 months.

Fetiform Teratoma (Homunculus)

Fetiform teratoma (homunculus) is a term that has been given to a rare form of ovarian teratoma that resembles a malformed fetus. There are very few reported cases of this entity in the English language literature. In this report, we document a case of fetiform teratoma in a 23-year-old woman, gravida 0, who initially presented with a chief complaint of dyspareunia. The clinical and pathologic aspects of this rare entity are presented here, with a review of the English literature. Differentiating fetiform teratoma from the more highly developed fetus-in-fetu and ectopic pregnancy is also discussed.

Fetiform Teratoma (Homunculus)

Fetiform teratoma (homunculus) is a term that has been given to a rare form of ovarian teratoma that resembles a malformed fetus. There are very few reported cases of this entity in the English language literature. In this report, we document a case of fetiform teratoma in a 23-year-old woman, gravida 0, who initially presented with a chief complaint of dyspareunia. The clinical and pathologic aspects of this rare entity are presented here, with a review of the English literature. Differentiating fetiform teratoma from the more highly developed fetus-in-fetu and ectopic pregnancy is also discussed.

Intraabdominal leg: Unique variant of split notochord syndrome

An infant was born with a spectrum of anomalies representing a unique variant of the split notochord syndrome. The major anomalies included giant omphalocele and duplicated lower spine, between which developed a posterior lumbosacral mass that was contiguous with an intraabdominal, skin-covered “leg” within a saccular cecum. Features of this case overlap aspects of fetiform teratoma, fetus-in-fetu, conjoined twins, and caudal duplication, suggesting an etiologic relation between these entities and split notochord syndrome.

Fetiform teratoma arising from a tubular intestinal duplication A probable cause of ruptured exomphalos

Fetiform teratoma arising from a tubular intestinal duplication A probable cause of ruptured exomphalos

Fetiform teratoma arising from a tubular intestinal duplication

A neonate who had a ruptured exomphalos with a fetiform teratoma arising from the end of a long intestinal tubular duplication and a short gut is presented. The management is discussed and the literature is reviewed.