[Iatrogenic metastasis of pineal tumors]

Malignant pineal tumors (PT) tend to metastasize. In rare cases, this process is provoked by surgery. This paper describes four cases of iatrogenic metastasis of PT. Metastasis occurred: a) along the surgical approach path after tumor removal in 2 cases; b) along the biopsy cannula path; and c) along the ventriculoperitoneal catheter into the abdomen. The sources of metastases were pineoblastoma (n = 1), malignant teratoma (n = 1), germinoma (n = 1), and malignant germ-cell tumor of unknown genesis (n = 1). To prevent this complication due to high-grade PT, such as malignant germ-cell tumors and pineoblastomas, radiation of the whole brain, besides the sites of a tumor should be performed and, in some cases, in combination with chemotherapy.