The disease was first identified in the second half of the 19th century. It is known more formally as glioblastoma multiforme. The first surgery performed on a patient with this type of tumor was done in Vienna in 1904. The incidence of glioblastoma is higher among Caucasians, especially if they live in industrial areas. Doctors do not fully understand the cause of these tumors. They arise spontaneously but sometimes develop in members of the same family, and they can also occur in patients with certain genetic diseases; both these observations suggest a possible genetic component. Glioblastomas are also more common in postmenopausal women, raising the question of whether hormones might be involved, and in taller, heavier people. These tumors rarely occur in children and infants. (2) The prognosis for patients with glioblastoma is usually not good, although it is gradually improving. Mark Gilbert, MD, the chief of the National Institute of Health’s Neuro-Oncology Branch, says, “We have seen incremental improvements in survival. The median length of survival was only 8 to 10 months in the mid-1990s, but it has almost doubled to 15 to 18 months now.” (3) But brain tumors are different. They usually do not spread outside of the brain, and they are graded, not staged. Those tumors with the highest grades tend to grow faster and spread more quickly. Tumor grade is based in part on how abnormal the tumor cells look, and on special stains performed on the biopsy, which are indicators of how fast the tumor is growing. (4) Some cells might look only slightly different from normal cells. They are referred to as “well-differentiated,” and they tend to grow more slowly than other tumors. Tumor cells with a very abnormal appearance, lacking structures found in normal cells, are classified as “undifferentiated” or “poorly differentiated.”
Grade 1: These tumors typically grow slowly and do not grow into (invade or infiltrate) nearby tissues. They can often be cured with surgery.Grade 2: These tumors also tend to grow slowly but they can grow into nearby brain tissue. They are more likely than grade 1 tumors to come back after surgery. They are also more likely to become faster-growing tumors over time.Grade 3: These tumors look more abnormal under the microscope. They can grow into nearby brain tissue and are more likely to need other treatments in addition to surgery.Grade 4: These are the fastest-growing tumors. They generally require the most aggressive treatment. (5)
AgeFunctional level; whether the tumor is affecting normal brain functions and everyday activityThe grade of the tumor; how quickly the tumor is likely to grow, based on how the cells look under a microscopeIf the tumor cells have certain gene mutations or other changes; for example, tumors with a mutation in the IDH1 or IDH2 gene, known as “IDH-mutant” tumors, tend to grow more slowly and have a better outlook than tumors without these mutationsThe location and size of the tumorHow much of the tumor can be removed by surgery (if it can be done)Whether or not the tumor has spread through the cerebrospinal fluid to other parts of the brain or spinal cordWhether or not tumor cells have spread beyond the central nervous system (6)
A patient’s symptoms can also help determine the outcome. Seizures and having symptoms for a long time are linked with a better prognosis.
Gross Total The entire tumor was removed, but microscopic cells may remain.Subtotal Large portions of the tumor were removed.Partial Only part of the tumor was removed.Biopsy Only Only a small portion, used for a biopsy, was removed. (7)
