Sen. Edward "Ted" Kennedy, D-MA, died at his home in Cape Cod, Massachusetts, after a year-long battle against brain cancer on August 25, 2009.

In 2008, a biopsy of a suspicious growth in the late senator's left parietal lobe revealed a malignant glioma, the most common type of brain tumor. It is diagnosed in some 25,000 Americans a year, and in 30% to 40% of cases, the first sign of the disease is a seizure — as was the case with Kennedy. Glioma is a cancer of the brain that begins in glial cells, the cells that surround and support nerve cells. Glioma, the type of brain tumor that afflicted Sen. Edward Kennedy is the most prevalent type of adult brain tumor.

Malignant gliomas are the most common primary brain tumor, accounting for more than half of the more than 18,000 primary malignant brain tumors diagnosed each year in the United States. These tumors are the second-most common cause of cancer death in the 15 to 44 age group.

The outlook for patients with malignant gliomas is poor. Median survival for patients with moderately severe (grade III) malignant gliomas is three to five years. For patients with the most severe, aggressive form of malignant glioma (grade IV glioma or glioblastoma multiforme), median survival is less than a year.

Surgery is recommended for all operable brain tumors and is usually followed by radiation therapy. Several studies have shown that adding chemotherapy to radiation can improve patients' survival. In June 2004, after the completion of the current study, researchers announced that adding the drug temozolomide (Temodar®) to radiation therapy increased median survival in patients with glioblastoma multiforme by about two months (see related story). This approach is now considered the standard of care for the initial treatment of these tumors.

The treatment patients received conformed with practice guidelines in some respects and departed from them in others. For example, most patients underwent contrast-enhanced magnetic resonance imaging (MRI) at diagnosis. This imaging test is almost universally accepted as the test of choice for diagnosing malignant glioma.

Also in keeping with practice guidelines, most patients had surgery to remove as much of the tumor as possible, followed by postoperative radiation therapy. However, only 54 percent received chemotherapy, despite the fact that chemotherapy has been shown to improve survival.

Other aspects of patients' care conflicted with best practice recommendations. For example, the American Academy of Neurology (AAN) recommends treating glioma patients with anti-epileptic medications only if they have seizures as a symptom when their tumor is diagnosed. Because these drugs can have severe side effects, the AAN advises against prescribing them routinely to all patients with newly diagnosed malignant gliomas. Nevertheless, nearly 90 percent of patients in this study received anti-epileptic medications, although only 32 percent had seizures.

Several areas of patients' care reflected a lack of agreement on best practice. For example, studies of the safety and effectiveness of giving low-dose anticoagulants to prevent post-surgical blood clotting in glioma patients have produced conflicting findings. In this study, only 7 percent of patients received preventive anticoagulants, although as many as 60 percent developed blood clots within six weeks of surgery.

Thirteen percent of newly diagnosed patients reported symptoms of depression. However, only 28.6 percent of these patients received antidepressant medications. Patients' doctors may have been concerned about the possible side effects of giving antidepressants to patients who were also taking anti-epileptic medications, the study authors say. The likelihood of such adverse effects is not known.

Almost all patients received corticosteroid medications to reduce neurologic symptoms, although these medications may cause significant adverse effects such as diabetes, high blood pressure, muscle pain, and increased susceptibility to infections.