Gliomatosis cerebri is a rare type of brain tumor. It most commonly presents itself as a diffusely infiltrating tumor involving more than one lobe of the brain. It is typically a high grade glioma, which means it involves the "glial" cells or connective tissue of the brain.
Sometimes Gliomatosis is considered a "mixed" glioma when the tumor contains both astrocytes ( a kind of star-like shaped glial cell) and oligodendrocytes ( another kind of glial cell)
It is generally considered a highly aggressive malignant tumor, which means it contains cancer cells, and is therefore a brain cancer. ( Benign tumors do not contain cancer cells ). Primary Gliomatosis Cerebri is more common in children, but does occur in adults also.
It differs from most brain cancers in the way it grows. There generally is no single tumor mass, but infiltrates through different parts of the brain as it grows. It has been described to us being similar to sand spilling, or milk spilling, where it spreads in and around other brain cells, instead of a single mass which grows larger in size.
How is gliomatosis cerebri classified?
The World Health Organization classification scheme includes 4 grades of glioma. Based on how the cells look under a microscope. Grades 1 and 2 are considered low grade, and Grades 3 and 4 are considered high grade gliomas.
However, since only a fraction of gliomatosis cerebri tumors are biopsied, it can be difficult to conclusively assign a grade to them. ??That said, they are aggressive tumors and usually progress like a high grade tumor ( grade 3 or 4) and are treated like a high grade tumor.
Incidence of gliomatosis cerebri
Gliomatosis Cerebri is a very rare brain tumor. They represent less than 3 percent of pediatric brain tumors.
There are most likely less than 500 known cases of primary Gliomatosis Cerebri.
What causes gliomatosis cerebri?
There are no known factors or conditions that make a person more or less likely to develop gliomatosis cerebri.
What are the symptoms of gliomatosis cerebri?
Symptoms might come on slowly and subtly, or they might appear more abruptly. Each child may experience symptoms differently, the most common include:
" headache and lethargy?
" symptoms of increased pressure within the brain, including headache (generally upon awakening in the morning), vomiting, and seizures
" localized symptoms - these tumors invade normal tissue as they grow, and produce symptoms based on the part of the brain that it is located in. These could include weakness and other motor dysfunction, neuroendocrine problems, or changes in behavior or thought processes
How is gliomatosis cerebri diagnosed?
Physical Exam?- Following an assessment of symptoms, and a physical exam,
which may include a neurological exam, a Physician may order one or more of the following diagnostic tests.
CT or CAT Scan (computerized tomography scan) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. CT scans are more detailed than general x-rays.
MRI (magnetic resonance imaging) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body. MRI provides greater anatomical detail than CT scan and does a better job of distinguishing between tumors, tumor-related swelling and normal tissue. Younger children may be given a sedative to help them remain still during the test. The MRI test is loud and sounds like banging during the test, which should be explained to the child. Parents are generally allowed to remain in the room.
MRS (magnetic resonance spectroscopy) - a test done along with an MRI. It can detect the presence of organic compounds within sample tissue that can identify the tissue as normal or tumor, and may also be able to tell if the tumor is a glial tumor or if it is of neuronal origin (originating in a neuron, instead of in a brain cell).
Biopsy or Surgery
A biopsy may be performed to assist in diagnosis of the brain tumor, and to attempt to remove as much of the tumor as possible. As typically the tumor is widespread and diffuse, it is difficult to remove the tumor during surgery.