Double fetus in fetu

Fetus in fetu (FIF) is an extremely rare cause of infantile abdominal mass where a rudimentary, malformed monozygotic-diamniotic twin grows inside the other twin. We describe a male infant with double or twin fetuses in fetu. The diagnosis was made on a computerized tomography (CT) scan of the abdomen and confirmed on surgery. Surgical excision was done and the baby did well post operatively.     

Intraventricular twin fetuses in fetu

The authors report a rare case of multiple intracranial fetuses in fetu, fulfilling Willis' traditional criteria, which include an axial and appendicular skeleton with surrounding organized tissue. This case was ascertained from studies of a full-term female neonate who presented with ventriculomegaly. A CT scan showed intracranial calcifications that were suggestive of an axial skeleton. Her birth weight was 3.176 kg (50th-75th percentile), length was 52 cm (90th percentile), head circumference was 35 cm (50th-75th percentile), and Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. Prenatal ultrasonography studies performed at 12 weeks and 5 days, and 19 weeks and 6 days revealed normal findings. A 37-week prenatal ultrasonography study showed ventriculomegaly and obstructive hydrocephalus, with a possible intracranial teratoma. Cranial imaging at birth with ultrasonography, CT and MR imaging, and MR angiography demonstrated 2 complex intraventricular masses with cystic, solid, and bony elements. A craniotomy with resection of the masses was performed at 3 months of age. The infant survived and is now 12 months old with some developmental progress. Two axial skeletons, with accompanying rib cage and extremities, including well-formed feet and toes, were noted. Both anencephalic structures had skin with hair, fat, skeletal and smooth muscle, and bony structures with bone marrow and focal areas of calcification. Multiple viscera were present and included thymus, bowel, stomach, salivary gland, kidney, adrenal gland, lung, and presumed adnexal structures. A diagnosis of fetuses in fetu was rendered. Chromosomal studies of the child and tissue from the 2 fetuses in fetu showed normal female karyotypes. A single nucleotide polymorphism array analysis from the proband infant and tissue from the 2 identified fetuses in fetu appeared to be genetically identical. These results are consistent with a monozygotic twin embryonic origin of the fetus in fetu tissue, which is a mechanism that has been suggested in previous reports in which karyotypes, blood types, and limited genetic loci have been studied. This is the first report of a rare example of intracranial intraventricular twin fetuses in fetu for which a genome-wide single nucleotide polymorphism assay has confirmed their genetic identity.     

Multiple fetuses in fetu:imaging findings

Fetus in fetu is an extremely rare developmental abnormality secondary to abnormal embryogenesis in a diamniotic monochorionic pregnancy. It occurs when a vertebrate fetus is enclosed within the abdomen of a normally developing fetus. This report describes the prospective diagnosis of fetus in fetu by findings on a plain radiograph and CT scan. At surgery, two fetus in fetu were discovered.     

Oropharyngeal fetus in fetu

Fetus in fetu is an extremely rare entity and refers to the growth of a parasitic twin within a more mature fetus due to its inclusion within cells of the blastocyst. The presence of a vertebral column is considered essential for the diagnosis of a fetus in fetu. The retroperitoneum is the most common location for a fetus in fetu and its location in the mouth is rare. We report a case of oropharyngeal mass detected on antenatal sonography with imaging features consistent with a fetus in fetu. Complete surgical removal of the mass was aided by imaging. Follow-up of these patients is recommended to detect the rare incidence of malignant degeneration.     

Fetus in fetu: a case report and literature review

Fetus in fetu is a rare condition in which a fetiform calcified mass often is present in the abdomen of its host, a newborn or an infant. We report on a case of a 19-month-old girl whose plain abdominal radiograph, ultrasonography, and computed tomography scan revealed a mass in which the contents favor a fetus in fetu rather than a teratoma. The noncalcified vertebral column invisible on the radiographs was identified by the pathologist; therefore, the nonvisualization of the vertebral axis on radiography or on computed tomography scan does not exclude the diagnosis of fetus in fetu.     

Intraperitoneal testicular fetus in fetu

A 5-month-old boy presented with a right flank abdominal mass. Plain film of the abdomen showed a vertebral column within the mass. Surgery confirmed the diagnosis of fetus in fetu developed within an ectopic intraperitoneal right testicle. Fetus in fetu differs from teratoma by the presence of axial skeleton and organogenesis. When intratumoral axial skeleton is present, plain films are sufficient for the diagnosis.     

MRI reveals fetus in fetu in the mediastinum

Fetus in fetu is an extremely rare condition in which a fetiform calcified mass is contained within the newborn or infant, often in the retroperitoneal cavity. We report a case of a fetus in fetu in the posterior mediastinum of a newborn. The prospective diagnosis was made by fetal US and MRI and confirmed by postnatal plain radiograph, CT and MRI.     

Fetus in Fetu: A Case with Complete Umbilical Cord and Fetal Sac

The authors present a retroperitoneal fetus in fetu in a 3-month-old girl. A 15-cm cystic mass with a monstrous fetuslike structure surrounded by a complete sac containing serous fluid was removed from the left retroperitoneal space. The draining vessel of the cystic mass was connected to the right renal vein of the host. The included fetus weighed 380 g. It had a well-developed umbilical cord, four extremities, head, buttock, and vertebral bodies with a meningomyelocele. The thoracic cavity of the included fetus had only a saclike foregut structure, but the abdominal cavity revealed a full length of intestine with a Meckel diverticulum, bilateral ovaries, urinary bladder, and cloaca with external opening. The cephalic end was composed of well-developed tooth germs, tongue and buccopharynx, mandible, maxilla, sphenoid bone, and salivary glands. Chromosomal study showed 46,XX with a normal G banding pattern. We report this case as an example of fetus in fetu with a complete umbilical cord and fetal membrane.     

Fetus in fetu: report of three cases and review of the literature

Fetus in fetu, or parasitic twin, is an uncommon condition in which a malformed fetus grows within the body of its twin. It is almost always detected as an abdominal mass in infancy: 41 cases have been reported since 1806 and 89% of the patients were less than 1 year old. We have reviewed the literature and report three new cases from our own experience. All patients available were considered from the point of view of their clinical findings, preoperative diagnosis, surgical and anatomic-histological aspects. We also suggest the possibility of including those cases otherwise defined as teratomas with a high grade of structural complexity (limbs, well formed organs, or parts of systems) in this pathological group even if they do not show a real vertebral column according to Willis' definition.     

Association of a fetus in fetu and two teratomas: US and MRI

We report a case of an abdominal mass in a newborn girl containing a fetus in fetu and two teratomas. Obstetrical sonography revealed the abnormality at 28 weeks of gestation. Post-natal US examination suggested the diagnosis of a fetus in fetu upon the finding of a vertebral column and fetal skeletal bones. US also showed two other rounded masses connected to the main lesion by vascular bundles. Preoperative MRI examination supplied further information regarding tissue composition and vascularisation of the mass lesion. The diagnosis was confirmed by pathological examination. Aetiological factors and radiological diagnosis of this rare tumour are reviewed and discussed. Received: 29 January 1996 Accepted: 2 February 1996     

Fetus in fetu

Fetus in fetu is a rare condition in which a monozygotic, monoamniotic, dichorionic twin is included within the body of its sibling [19]. In 1956, Lord presented the first systematic review of the subject, comprising 11 case reports including 1 of her own. She found that many of the earlier reports dealt with teratomas and not true fetus in fetu. In 1958, Willis defined fetus in fetu as a benign mass with a vertebral column, as identified by radiography or at dissection, with other bones and organs arranged around the axis. This is to be differentiated from a true teratoma, which shows no axial arrangements and has definite malignant potential [26]. This paper presents a case occurring in a newborn male and a review of the literature since Lord's initial review. Offprint requests to: S. Sutherland     

Fetus in fetu: a case report

A fetus in fetu is defined as a condition where a parasitic twin is found included within the body of its partner [8]. This is a report of a fetus in fetu treated successfully in a 4-mounth-old boy that fulfilled all the criteria of the disease. A brief review of the literature is also included.     

Fetus in fetu

A 1-year-old boy presented with a mass in the right upper abdomen. The radiological findings and gross features of the resected specimen indicated it to be a fetus in fetu rather than a teratoma.     

Fetus in fetu associated with an undescended testis

Fetus in fetu is an extremely uncommon cause of an abdominal mass in the neonate; fewer than 30 generally accepted cases are recorded in the literature. We report a case of intraabdominal fetus in fetu, with a unique location within an undescended left testicle. Chromosomal studies of cells from the fetus in fetu and the surviving infant revealed identical 46,XY karyotypes.     

Mucinous cystadenoma of the ovary in perimenarchal girls

Ovarian masses in children are an uncommon occurrence. They represent less than 2% of all tumours in girls less than 16 years of age. Mucinous tumours of the ovary occur principally in middle adult life and are extremely rare prior to menarche. To the best of our knowledge, there are only 13 previous cases of benign mucinous cystadenoma (MCA) of the ovary in perimenarchal girls reported in the literature. We present six cases of this rare tumour. We reviewed the charts of six patients who presented with large MCA of the ovary. The patient’s ages ranged from 13 to 14 years (mean 13.6 years). Two were premenarchal and four were within 1 year of menarche. All children presented with marked abdominal distension and discomfort. Except for one child who had ultrasound scan alone, all the others had either CT or MRI scan as well. Ultrasound demonstrated a large multiloculated cystic mass arising from the pelvis reaching the level of the xiphoid. CT demonstrated an enormous mass occupying almost the entire abdomen. The mass was partly solid, partly cystic and the cystic elements were multiloculated in all patients. Three patients demonstrated contralateral hydronephrosis on imaging. Laparotomy revealed a tumour arising from the left ovary in five patients and from the right ovary in one. Several litres of fluid were aspirated in order to deliver the tumour from the abdomen. All patients underwent oophorectomy or salpingo-oophorectomy. Histology revealed benign MCA of the ovary in all cases. On follow up, ranging from 2.4 to 5 years, all patients were well with no evidence of recurrence. MCA in perimenarchal girls usually affects the left ovary. Although this tumour is rare, this diagnosis should be considered in 11 to 15-year-old girls presenting with a very large abdominal mass.     

Mature cystic teratoma of the pancreas in a child

A cystic pancreatic tumour is rare in a child and a mature cystic teratoma of the pancreas is even rarer. This is the first demonstration of the CT appearance of such a tumour in a child. We present a 2-year-old boy who presented with a palpable abdominal mass. Abdominal CT revealed a huge cystic mass in the upper abdomen. Pathology disclosed a mature cystic teratoma originating from the pancreas.     

An unusual cause of meconium peritonitis in a foetus

Abstract:   Meconium peritonitis is a sterile chemical peritonitis resulting from intestinal perforation in-utero. We present a preterm male neonate weighing 1820 g in whom foetal meconium peritonitis was diagnosed by antenatal utrasonogram. Examination of the newborn in the immediate postnatal period revealed a firm lump of size 5 × 3 cm in the right lumbar and umbilical area. Rest of the abdomen was normal without any clinical evidence of intestinal obstruction. X-ray of abdomen done at 3 hours of life showed a cystic mass with calcified margin. Ultrasonography of abdomen ruled out any definite cause of intestinal obstruction and perforation. He was kept on conservative management. At 11 hours of life the neonate passed a small sticky white mucus plug per rectum followed by black colored meconium of normal consistency 2 hours later. The bowel habit remained regular thereafter. Screening for intrauterine infections and cystic fibrosis was negative. He is under regular follow-up and is now 6 months old with normal bowel habit. A lump of size 2 × 2 cm is still palpable and a small calcified mass is persistent in x-ray. Role of an intestinal mucus plug as the potential factor for intestinal obstruction and subsequent perforation has been highlighted in the present case.     

Sacral parasite with histopathological features of an unequally conjoined twin

A sacral parasite is a rare congenital anomaly classified etiologically as duplicitas asymmetros, where the parasitic mass is regarded as the tissue remnants of an unequally conjoined twin. We, herein, report a case of a sacral parasitic mass found in a female neonate. A huge sacral mass was found at 30 weeks of gestation by fetal ultrasonography. The fetus was delivered by a Caesarean operation at 37 weeks and 6 days of gestation. The alpha-fetoprotein (AFP) level was 174,640 ng/ml. The mass separated by an operation on the day after her birth, contained structures similar to imperfect limbs and backbone. A variety of tissue and organs having derived from three germ layers were identified within the mass and showed a tendency to be highly differentiated. Even though a large proportion of the central nervous system tissue showed immature and dysplastic features, there were no evidences suggesting the presence of neoplasm. The infant has shown normal growth and is doing well without a recurrence of the sacral mass or any elevation in the serum AFP level during the12-month follow-up. We therefore believe that the present case should be considered a sacral parasite, rather than a sacrococcygeal teratoma. Although it should be recognized that such sacral parasite is very rare, this case provides further information that can be useful for diagnosis.     

Cystic renal involvement in tuberous sclerosis

We describe two cases of unusual presentation of tuberous sclerosis with cystic renal involvement. A 19-month-old white male who was initially misdiagnosed as having polycystic kidney disease of "adult-type" developed petit mal seizures and small "ash-leaf" depigmented areas, raising a suspicion of tuberous sclerosis. Computerized tomography (CT) of the brain revealed periventricular calcifications, confirming the diagnosis of tuberous sclerosis. A 15 3/4-year-old black female with tuberous sclerosis showed acceleration of renal failure. Computerized tomography scan of the abdomen showed cystic lesions of the kidneys. In young children with cystic renal involvement but a negative family history of tuberous sclerosis or polycystic kidney disease, a CT scan of the brain should assist in the diagnosis. A CT scan or ultrasound examination of the abdomen will differentiate cystic renal lesions from angiomyolipoma of the kidneys.