Choroid Plexus Carcinoma

Discussion Choroid plexus carcinoma most often occur in children between the ages of 2 and 4 years. Choroid plexus carcinomas account for 30-40% of choroid tumors in children. Patients may present with focal neurologic deficits, seizure or hydrocephalus. Choroid plexus carcinomas almost always grow into the brain through the ventricular wall and cause vasogenic edema. Intralesional cyst and hemorrhage are common. Choroid plexus carcinoma can be difficult to differentiate from aggressive choroid plexus papillomas. Both choroid plexus carcinomas and aggressive papilloma commonly metastasize by CSF pathways. Other tumors involving the choroid plexus are unusual and include meningioma, lymphoma, metastatic disease (neuroblastoma, retinoblastoma, Wilms, and melanoma), myofibromas and xanthogranulomas.

Primary neoplasms of the choroid plexus are uncommon lesions, constituting 1% to 2% of all childhood brain tumors(l).Choroid plexus carcinoma (CPC) is a very rare tumor.Choroid plexus papilloma (CPP) is a common primary choroid tumor and its prevalence is four times higher than CPC.CPC is often extensive at diagnosis occurs in infants and has a poor prognosis.In view of the rarity of this condition and paucity of data from our country (2,3), this case is being reported.

Case Report
A 2-year-old developmentally normal boy presented with 15 days history of alteration in sensorium, vomiting, seizures, and weakness of right half of the body with associated history of low grade fever.There was no history of cranial nerve involvement, decerebration or enlargement of head.Birth and immediate postnatal history were normal.On examination the child weighed 8.6 kg and the head circumference was 45 cm.He was afebrile and normotensive.On neurological examination the sensorium by the Glasgow coma scale showed best verbal response of 3, best motor response of 4 and best eye response of 2. Fundus showed early bilateral optic atrophy.The child had right hemiparesis with generalized hypertonia, hyper-reflexia and extensor plantar response.
Investigations revealed a normal X-ray chest, normal blood counts, and a nonreactive Mantoux test.Examination of the cerebrospinal fluid was normal.CT scan of the head revealed a large hyperdense enhancing lesion in the left lateral ventricle with an area of necrosis and generalised dilation of the ventricular system.MRI head (Fig. 1) showed a large heterogenous mass arising from the left lateral ventricle.
T he c hi l d wa s s u bj e c t e d t o neurosurgical intervention.Tumor decompression was done through a left parietal craniectomy.The tumor was encountered at a depth of 0.5 cm from the surface.It was vascular, soft with an illdefined plane of cleavage and grossly invasive.Histopathology of the tumor (Fig. 2) showed sheets of monomorphic cells with nuclei showing dispersed chromatin with small amount of amorphous cytoplasm.At places there was attempted gland formation and acinar pattern separated by thick fibrous septae with blood vessels; fair amount of mitotic activity was seen.The child was given radiotherapy post-operatively.

Discussion
CPP is the most common primary choroid tumor and in most series outnumbers CPC by a ratio of 4:1 (1,4,5).Both CPC and CPP may arise in the lateral, 3rd or 4th ventricle.All CPC in children occur in the lateral ventricles (67% left, 33% right) while most tumors in adult are in the fourth ventricle (6).
There The criteria for the diagnosis (10,11) of primary CPC are as follows: (i) Invasion of the adjacent neural tissue with infiltrating cells that assume a diffuse growth pattern; (ii) Loss of the regular papillary structure of the neoplasm where invasion is occurring and obvious malignant alteration in the cells; (in) transition of normal choroid plexus architecture to an undifferentiated pattern.Grossly both CPC and CPP are friable, vascular tumors.Histologically CPP are usually composed of a single layer of epithelium supported by well vascularised connective tissue.In CPC the regular architecture is lost, nuclei vary in size and mitoses are prominent.
Immunehistochemical staining is not useful in separating the two conditions.The therapy of CPC consists of surgical resection with adjuvant radiotherapy or chemotherapy.The prognosis for these tumors is poor.

PALS COURSE
The Department of Pediatrics, L.
T.M.G.Hospital and L.T.M. Medical College, Sion, Bombay under the auspices of IAP is organizing a 'PEDIATRIC ADVANCED LIFE SUPPORT' (PALS) Provider's Certificate course at L.T.M.G.Hospital, Sion, Mumbai 400 022 on 10th and 11th October 1996.Limited registration (Rs.600/-upto 1st August 1996 and Rs.700/-upto 31st August 1996) will be done on a first come first served basis for 35 delegates only till 31st August 1996.Registration fees should be sent in form of demand draft/cheque drawn in the name of "PEDIATRIC CRITICAL CARE SERVICE-L.T.M.G.H.".(For.outstation cheques, please add Rs. 25/-) on any of the following addresses.