Massachusetts Senator Edward Ted Kennedy has been diagnosed with a malignant brain tumor according to his Boston doctors. Survival rates range from 1-5 years.

Sen. Edward M. Kennedy’s seizure this weekend was caused by a brain tumor, his doctor said this afternoon, but it’s not yet clear if he will undergo radiation treatment and chemotherapy to treat the tumor.

The tumor, on Kennedy’s left parietal lobe, is known as a “malignant glioma,” according to his doctors, who did not give a long-term prognosis on Kennedy’s health and did not give details about the size or severity of this tumor. This type of tumor is the most common among adults, and the survival rates range from one to five years, depending on the severity of the tumor.

Edward is the brother of the late John F. Kennedy and Robert ‘Bobby’ Kennedy.

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