Loss of heterozygosity analysis in an anaplastic oligodendroglioma arising after radiation therapy

Anaplastic oligodendrogliomas after treatment of acute lymphoblastic leukemia in children: report of 2 cases

Radiation-induced brain tumors are suggested to be the late complication of acute lymphoblastic leukemia (ALL) treatment. High-grade gliomas, meningiomas, and sarcomas are the most frequent neoplasms. Secondary anaplastic oligodendrogliomas are exceedingly rare. Five cases of pure anaplastic oligodendroglioma have been reported in the literature, and only 1 case was in a child after ALL treatment. The authors present 2 cases of pediatric anaplastic oligodendroglioma after treatment of ALL. Furthermore, they performed a molecular cytogenetic study and found loss of 1p in both cases. The authors provide a review of the previous cases and discuss their findings.

Extraneural metastases of anaplastic oligodendroglial tumors

Extraneural metastases of malignant gliomas are rare. According to the literature, they tend to appear in glioblastoma patients, but are exceptionally rare in anaplastic oligodendroglioma. We report on an anaplastic oligodendroglioma and an anaplastic oligoastrocytoma that metastasized to cervical lymph nodes and bones. Both patients were women aged 54 and 30 years, and the metastases appeared following craniotomy. In the first patient, metastases to cervical lymph nodes developed one year after surgery, and, despite adjuvant therapy, recurred in the same location several times. Fine needle aspiration biopsy (FNAB) of the cervical lymph node prior to neck dissection suggested a possible metastatic primitive neuroepithelial tumor. In the second case, metastases to the sacrum and femur developed after surgery for a recurrent anaplastic oligoastrocytoma. Our two cases reconfirm a rare but definite ability not only of glioblastoma but also of anaplastic oligodendroglioma, namely to metastasize to extraneural sites. It is important to bear this in mind, particularly in cases when the history of primary brain tumor is unavailable. In such instances, the correct diagnosis of the metastatic lesion may be extremely difficult if not impossible.

Two metachronous tumors induced by radiation therapy: case report and review of the literature

Various radiation-induced tumors, including meningioma, glioma, and sarcoma, have been reported; however, metachronous intracranial double tumors induced by radiation therapy are extremely rare. A 1-year-old boy had undergone tumor removal and craniospinal radiation therapy (30 Gy) for cerebellar medulloblastoma. At 24 years old, parasagittal meningioma developed in the left parietal region and was totally removed. Six years later, an infiltrative tumor was newly found in the right fronto-temporal white matter. The patient underwent stereotactic biopsy, and the tumor was found to be an anaplastic astrocytoma. Chromosomal analysis by fluorescence in situ hybridization (FISH) revealed loss of heterozygosity (LOH) of 1p. As the patient had previously had craniospinal irradiation, no additional radiation therapy was delivered. He underwent chemotherapy with temozolomide and the disease is now stable. Since both secondary tumors were located within the area of previous radiation and the patient did not have any genetic disease predisposing him to tumors, radiation therapy was considered to be responsible for their tumorigenesis. To our knowledge, this case is the fourth case of radiation-induced double CNS tumors arising after radiotherapy to be described in the literature. Whenever radiation is administered to children or young adults, careful serial screening studies are needed.