Choroid plexus carcinoma: A case report and literature review

Abstract

Introduction: Choroid plexus tumors represent 0.5% of the tumors. Choroid plexus carcinoma is a malignant tumor, Grade III (WHO), which represents ~ 0.4 - 0.6% of all brain tumors. The ratio between the papilloma and choroid plexus carcinoma is 5 : 1. Clinical case: A girl of 1.5 years has facial paralysis, morning vomiting, gait instability, and stagnation of weight of 2 months of evolution. The brain CT shows a space-occupying lesion in the left cerebral hemisphere, parietal low, and voluminous, collapsing occipital horn of the lateral ventricle on that side, midline shifting slightly and causing hydrocephalus, with areas of internal necrosis. Intraoperative cytological study was performed, we found plaques, papillae groups and mediumsized cells with atypical nuclei and eosinophilic nuclei without fibrillar bridges among them. Histological examination presented central fibrovascular cores lined by columnar cells with varying degrees of stratification evident for atypical and abundant mitoses. In wide areas papillary pattern disappears and takes a solid pattern, with formation of nests and diffuse areas of anaplastic cells with marked pleomorphism and mitotic activity. Invasion was observed surrounding brain tissue. The neoplastic cells express immunophenotype positive for CK8, S100 and vimentin and focally positive for GFAP. EMA and SV40 virus were not expressed. Diagnosis was performed of choroid plexus carcinoma. The patient had a hypothalamic recurrence 4 years after diagnosis, she was treated with chemotherapy and radiotherapy, having a clear reduction of the tumor. A year later she presented with progressive thrombocytopenia that obliged to stop chemotherapy, suffering progressive deterioration, she was diagnosed with secondary AML 1 year later. She had symptoms of aplastic anemia and infection with poor outcome and death in the same year. Discussion: These are rare tumors with a typical presentation in childhood. They have been associated with SV40 virus infections. In our case we have not demonstrated viral protein with immunohistochemical techniques. The cytological findings in extended "smear" are quite characteristic and can guide the diagnosis. The morphological and immunohistochemical analyses allow definitive diagnosis. The differential diagnosis arises mainly ependymomas and rhabdoid tumor/atypical teratoid at early ages and with metastatic adenocarcinoma in adults.