Study backs dual therapy for brain cancer
Method parallels Kennedy regimen
The treatment regimen described in the journal Lancet Oncology parallels the approach used by cancer specialists to treat Senator Edward M. Kennedy, the Massachusetts Democrat who was diagnosed in May with a malignant brain tumor.
The researchers, based at hospitals in Europe and Canada, gave patients both radiation and a chemotherapy drug called temozolomide for six weeks; patients then continued taking the drug alone five days a month for the following six months.
The combination therapy proved superior to radiation alone at every milestone measured. After three years, for example, 16 percent of the patients who had received radiation and chemo were still alive, compared with just 4.4 percent of those who had only radiation.
The survival difference was even more pronounced at the five-year mark, with patients who had received the combination regime five times more likely to be alive.
Cancer specialists hailed the findings as hopeful for patients with brain tumors, but cautioned that the disease remains exceptionally difficult to defeat.
"This is a true advance for the field," said Dr. Tracy Batchelor, chief of neuro-oncology at the Massachusetts General Hospital Cancer Center, which is overseeing Kennedy's care. "We are very happy to see that these beneficial effects are sustained for up to five years in this patient population, but nevertheless, it is not the cure that we are all looking for."
For years, doctors had little to offer brain cancer patients other than surgery to remove the rapidly spreading tumor, followed by radiation to bombard as many stray cancer cells as possible. But the results were dismal, with few patients surviving longer than two years.
When temozolomide was first tried as a stand-alone treatment, results were disappointing, said Dr. René-Olivier Mirimanoff, senior author of the study published yesterday. But then researchers in Switzerland decided to see what would happen if they gave it at the same time as radiation.
"The results were fairly amazing because for the first time, we could see the survival of patients was beyond two, three years," said Mirimanoff, a radiation oncologist at University Hospital in Lausanne, Switzerland.
The scientists then embarked on the larger study that was reported yesterday. They followed 573 patients, with half receiving combination therapy and half getting radiation exclusively.
Specialists theorize that the chemotherapy drug boosts the potency of radiation therapy. What's less clear, though, is how much temozolomide helps on its own during the period after radiation.
The study conducted in Europe and Canada limited participation to patients 70 and younger; Kennedy was 76 when he was diagnosed with brain cancer. Batchelor said there is preliminary evidence from other studies that older patients derive similar benefits when treated with radiation and temozolomide together, although that has not been established definitively.
Younger, healthy patients - those under 50 - benefited the most from the combination treatment, with up to 28 percent still alive after five years. Patients whose tumors carried a certain genetic profile also tended to fare better, further evidence, researchers said, that gene fingerprinting can help design more effective treatment protocols.
Mirimanoff, who trained in radiation oncology at Mass. General, said the modest success of the combination treatment had fueled a notable shift in attitude among doctors, especially when confronted with patients whose cancer had returned.
Now, he said, doctors appear more willing to suggest a second surgery to patients, followed by radiation and chemotherapy.
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