Occipital anaplastic oligodendroglioma with multiple organ metastases after a short clinical course: a case report and literature review.
BACKGROUND
It is generally believed that malignant gliomas never metastasize outside the central nervous system (CNS). However, the notion that oligodendrogliomas (OGDs) cells cannot spread outside CNS is being challenged.


METHODS
We described in detail the clinical story of one patient with anaplastic OGD, which metastasized to lymph nodes, bone marrowand bones Genetic analyses included detection of 1p and 19q chromosomal arms, methylation status of MGMT promoter, and PTEN exon mutations. A search of worldwide literature was conducted for reports of metastatic OGDs using NCBI-PubMed, with the keywords "extracranial", "extraneural", "oligodendroglioma", "oligodendrogliomas", "metastatic", "metastasis", and "metastases", in different combinations.


RESULTS
An open biopsy of the infiltrated bones in our patient revealed that malignant cells had replaced the patient's marrow. Moreover, the diagnosis of multiple-organ metastases of anaplastic OGD was confirmed based on immunohistochemical staining. Genetic analyses showed that the tumors originated from previously resected brain lesions. None of the lesions had 1p and 19q deletions, but hypermethylation of MGMT promoter, and the G → A transversion at codon 234 of PTEN exon 2 were detected. Literatures review yielded 60 reports of metastatic OGDs from 1951 to the present, which with our patient makes 61 cases. Concerning these 61 patients, there were 110 infiltrated sites correlated closely with primary OGDs. The most frequent metastatic sites were bone and bone marrow (n = 47; 42.7%), lymph nodes (n = 22; 20.0%), liver (n = 7; 6.4%), scalp (n = 6; 5.5%), lung (n = 6; 5.5%), pleura (n = 4; 3.6%), chest wall (n = 3; 2.7%), iliopsoas muscle (n = 2; 1.8%), soft tissue (n = 2; 1.8%), and parotid gland (n = 2; 1.8%).


CONCLUSIONS
Extracranial metastases in anaplastic OGD are very rare but they do occur; bone and bone marrow may be the most common sites. Detection of certain molecular markers such as deletion of 1p and 19q chromosomal arms, hypermethylation of MGMT promoter, and characteristic PTEN exon mutations may help differentiate subtypes which are more prone to extracranial metastases.
The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8749838611478560.
Gang
G
Li
Zhiguo
Z
Zhang
Jianghong
J
Zhang
Tianbo
T
Jin
Hongjuan
H
Liang
Li
L
Gong
Guangbin
G
Cui
Haixia
H
Yang
Shiming
S
He
Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, P,R China. zhangys_td@163.com.
Yongsheng
Y
Zhang
Guodong
G
Gao
D019046:Bone Marrow Neoplasms / Q000235:genetics / Q000556:secondary; D001859:Bone Neoplasms / Q000235:genetics / Q000556:secondary; D001932:Brain Neoplasms / Q000235:genetics / Q000473:pathology*; D006801:Humans; D008207:Lymphatic Metastasis / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009778:Occipital Lobe / Q000473:pathology*; D009837:Oligodendroglioma / Q000235:genetics / Q000556:secondary*