Shunt-related abdominal metastases in a child with choroid plexus carcinoma: case report.

OBJECTIVE AND IMPORTANCE: Metastasis of primary brain neoplasms to the abdomen through a ventriculoperitoneal shunt (VPS) has been described for many types of tumors, including medulloblastoma, germ cell tumors, astrocytoma, oligodendroglioma, lymphoma, ependymoma, and melanoma. Choroid plexus tumors (CPTs) are located within the cerebrospinal fluid-containing spaces of the brain and frequently disseminate throughout the craniospinal subarachnoid space, yet VPS-related metastasis of a CPT to the abdomen has not been reported previously.

CLINICAL PRESENTATION: We present the case of a 3-year-old boy with choroid plexus carcinoma of the lateral ventricle and preoperative intraventricular dissemination of the tumor. The patient later developed VPS-related abdominal metastases causing abdominal ascites.

INTERVENTION: Surgical resection of the tumor was followed by chemotherapy and craniospinal radiation, but the tumor further disseminated throughout the craniospinal subarachnoid space. When the child presented with abdominal ascites, the distal VPS catheter was externalized and drained cerebrospinal fluid at a rate of more than 750 ml/d. Paracentesis was performed for persistent ascites, and cytological analysis of the fluid revealed metastatic tumor cells.

CONCLUSION: The child died from widely metastatic tumor and aspiration pneumonia. CPT metastasis to the abdomen through a VPS should be considered in patients with the appropriate clinical findings. This condition may exacerbate overproduction of cerebrospinal fluid, which can occur with CPTs, and treatment must be individualized. Unusual options may be considered, such as long-term shunt externalization or paracentesis.