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Congenital intracranial teratoma of the lateral ventricle. Correspondence Address:
A case of lateral ventricular teratoma in neonate, where near total excision of tumour was done, is being reported with the review of literature.
Intracranial teratoma of the lateral ventricle occuring in the neonate is an extremely rare entity. Although the first teratoma of the lateral ventricle was reported in 1961 by Maier, review of literature revealed that, there are only few case reports of the surgical excision of lateral ventricle teratomas.[1],[2] We are reporting a case of congenital lateral ventricle teratoma, where near total extirpation of the lesion was performed. Pertinent literature, regarding its genesis, clinical and radiological presentation and treatment options, has been reviewed.
A 2 months old male child was admitted with a history of progressive macrocephaly and recurrent generalised clonic seizures since birth. Parents complained that for the past 45 days, he was not taking adequate feeds. The child was the first issue of a non-consanguineous marriage, born as full term normal delivery, with an APGAR score of 10 at 5 minutes. On examination, he had spontaneous eye opening, a feeble cry to painful stimuli and normal pupils. The child had normal tone and symmetrical movements in the extremities. Plantar response was extensor bilaterally. The head circumstances was 56 cm and he had anterior fontanelle with split cranial sutures and prominent scalp veins. CT scan head revealed a large, lobulated mass with speckled calcification in the temporal horn and the trigone of left lateral ventricle with considerable enhancement on contrast administration. The lateral and third ventricle were dilated with periventricular lucency. The fourth ventricle was of normal size. There was midline shift to the right [Figure - 1]. A left temporoparietal craniotomy was performed and the tumour approached through the middle temporal gyrus. A large grayish-white lobuted vascular mass was encountered under the ependyma, filling the temporal horn and trigone. At the time of surgery, near total removal of tumour was done. Histopathology revealed foci of squamous epithelium, cartilage, osteoid tissue, mucin secreting glandular tissue and at places proliferative primitive elements suggestive of teratoma [Figure - 2]. The postoperative course was uneventful and the child was discharged on the seventh postoperative day, with a normal cry and better spontaneous movements. On follow up after a year, the child was recognising mother and reaching out at objects but neck holding was poor. CT scan head done almost one year later revealed residual tumour in the trigone and occipital horn of lateral ventricle. The hydrocephalus had reduced and there was bilateral subdural effusion [Figure - 3]. The patient was followed for 2 years after surgery. His milestones were delayed. Fontanelle was almost closed. CT scan was advised again but the attendants did not get it done.
Teratomas most commonly arise in the ovaries and testis. In relation to the nervous system, the most common site is the sacrococcygeal region. Within the brain, they arise in the midline anywhere from optic chaiasma to pineal gland.[3] Teratoma constitute 0.5% of all intracranial tumours[4] and 2-4% of intracranial tumours in children.[1],[5] The incidence of brain tumours of congenital origin in the neonate period is 0.34 per million live births. However, Takaku et al[6] found greater incidence of these lesions (more than 50%) in a series of 103 patients of brain tumours in children aged 2 months or less. Majority of these neonatal tumours were supratentorial, in contrast to the usual infratentorial location in older children. Breslau reported the first case of massive congenital intracranial teratoma in 1864.[7] Teratomas are tridemal and originate during the 3rd and 4th week of embryonic development, where all cells are totipotential.[5] Their progressive uncoordinated growth is a pointer to their being truly neoplastic,[8] composed of multiple tissues foreign to the site in which they arise.[4] However, extragonadal teratomas, which are usually congenital and in the midline have been proposed to represent misplaced conjoined twin pregnancies with diploid cells, while gondal teratomas, which appear later in life are considered to arise from sequestered haploid germ cells.[9] Their preferential midline and paramedian location implicates the anomalies of primitive streak or its derivatives.[2] Intracranial teratomas may arise from the pineal gland, quadrigeminal plate, walls of the third ventricle, suprasellar region or cerebellar vermis.[10] Their location in the lateral ventricles, as in the present case, is rare and is probably related to the choroid plexus.[10] Oiset et al have defined tumours as being definitely congenital, probably congenital or possibly congenital depending upon whether the symptoms were present at birth, within the first week or within the first month of life respectively.[11] Our patient, who presented with progressive macrocephaly and seizures since birth therefore represents the 'definitely congenital type'. Three types of congenital intracranial teratomas have been described[12] : i) massive teratomas replacing the intracranial contents of a neonate, ii) small teratoma producing hydrocephalus iii) teratomas extending into the orbit or neck. These lesions may be solid or cystic and each contains portion of the others. Tumours of mature tissues are usually benign while those of embryologically immature tissues are usually malignant.[2] However, admixtures usually occur. Lungs are the commonest site of distant metastasis.[13] The prenatal diagnosis of intracranial teratoma, considered to be a rare event, is becoming more common because of wide availability of ultrasonography and computed tomography.[14] Considering all age groups, teratomas predominate in the males. However, in the neonatal period, the incidence is higher in females.[5],[15] The lesion usually presents clinically with macrocephaly.[2] Hydrocephalus occurs prior to the demonstration of massive intracranial tumours.[1] This is due to the early obstruction of the CSF pathway by the midline tumours, followed by effacement of the brain by the continued linear growth of the tumours.[12] Due to the cephalopelvic disproportion, dystocia and extremely difficult deliveries, caesarian section are common.[14] Spontaneous rupture of the skull may also occur during delivery. Ultrasonography seems to be superior for specific diagnosis of intracranial teratoma in-utero.[16] In-utero diagnosis of intracranial teratomas may be suspected by the abnormal rate of uterine growth and is established by the ultrasonographic findings of polyhydramnios, enlarged biparietal diameter, hydrocephalus, solid and cystic intracranial lesions and distortion of the normal intracranial anatomy.[14],[17] Usually, antenatal diagnosis is made at or after twenty weeks of gestation.[14] Intracranial calcification is usually seen and are more apparent by computerized tomography.[5] Various elements of teratomas can be identified by MRI. The cysts show short T1 and long T2 values. Fatty part displays long T1 and T2 values. Calcium, due to its low proton density, exhibits low signal intensity in both T1 and T2 images; hence visualization is difficult. The relationship of these midline lesions to the ventricles and brainstem is well visualised by multiplanar, sagittal and coronal images of MRI.[5] Malignant intracranial teratomas such as embryonal cell carcinoma may elaborate, germ cell markers (alpha-feto protein and human chorionic gonadotropin) in CSF and serum, that correlate with tumour activity and may enable early diagnosis of tumour recurrence. However, benign teratomas do not elaborate these markers.[2],[10] Various treatments modalities have been used, aimed at CSF diversions plus surgical biopsy or subtotal or complete removal. Teratomas have an inherent tendency to grow; therefore, complete surgical excision should be attempted.[2] The operative mortality of intracranial tumours, excised in the first year of life is 20%.[18] Complete excision may not be possible if the tumour is massive and has replaced large portions of the telencephalon.[1],[19] Ferreira[14] felt that chemotherapy may help delaying the re-growth of tumours and thus allow the CNS to become more resistant to the detrimental effects of radiotherapy. However, these modalities may damage the developing brain.[1],[2] These considerations deterred us from giving postoperative irradiation after near total resection. Mature teratomas which are benign may be reoperated at recurrence.[2] Herder and Ventureyra[2] reported recurrence after four month of successful excision. Takaku et al[20] reported recurrence after two year, although long term survival may be possible. However, risk of neurological deterioration is high.[17] Palliative ventriculo peritoneal shunts in neonates with non resectable lesion, repeatedly malfunction due to high protein content of the CSF.[1] The overall experience with this condition is disappointing. However, with improved methods of diagnosis and management, selected cases may be treated with more success in the future.[1] Despite all efforts, the 5 year survival was 18% for malignant teratomas in the series reported by Ferreira.[14] Surgical excision, where ever possible, can be curative.[16] Most neonates who have survived operation, fail to develop normally and develop neuropsychological changes. At two year follow up, our patient continue to have delayed milestones inspite of initial post operative improvement.
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