• 11/7/2006
  • Washington, D.C.
  • Christine Dell’Amore
  • United Press International (www.upi.com)

A series of new international studies on cancer therapies has identified treatments that may improve survival and limit harm to patients, researchers reported Monday.

A phase-III randomized trial in Canada has suggested the use of “intensity modulated radiation therapy,” or IMRT, reduces more painful side effects than the traditional form of radiation for women with breast cancer.

“This is the first study that proves all the investment we’ve done in new technology has translated into a patient benefit,” said researcher Dr. Jean-Philippe Pignol, an associate professor at the University of Toronto.

Pignol and other researchers presented their preliminary findings during a news briefing at the American Society for Therapeutic Radiology & Oncology, or ASTRO, meeting in Philadelphia. All of the research presented was preliminary, meaning it has not been peer-reviewed and may change.

Most women who get breast cancer will have surgery followed by radiation. But the standard radiation technique for breast cancer, called the wedge compensation technique, can cause painful skin irritation and burns along the breast and the breast crease, most often in women with large breasts. The burns can be severe enough to reduce quality of life, Pignol said.

In the trial of 358 patients, Pignol and colleagues assigned patients to either the standard treatment or an intervention of IMRT. In the study, 50 percent of the women had burns resulting from treatment.

Pignol found IMRT, which is able to deliver a high dose of radiation directly to the tumor, prevented skin burn to the breast two times more than the standard therapy.

The study demonstrates how, once a treatment for cancer is secured, subsequent research can best figure out how to minimize side effects, said Dr. Theodore Lawrence, immediate past chair of ASTRO and a professor of radiation oncology at the University of Michigan, Ann Arbor.

“We need to strongly applaud this study for subjecting — at the highest level of intellectual rigor — a new technology versus a standard technology,” Lawrence said.

It’s possible IMRT might someday reduce side effects in prostate cancer and head and neck cancers, Pignol added.

In a European trial on chemotherapy and radiation for patients with non small-cell lung cancer, new evidence suggests different techniques may be preferable based on the progression of the disease.

Dr. Jean-Yves Douillard of the Centre Rene Gauducheau in Nantes, France, studied 840 patients of varying stages of lung cancer, who had the option to get radiation on top of their chemotherapy between 1995 and 2004. The study was not randomized, and so the results can only inform future hypotheses.

The observational data showed radiation provides an additional benefit to chemotherapy in patients with more advanced lung cancer, or whose cancer has spread to the lymph nodes. But it can be damaging to patients with less severe forms of the disease, Douillard reported.

The research confirms other studies on resected, or operable, lung cancer, which found radiation therapy improves survival of those with serious lymph node cancers.

In Douillard and colleagues’ study, those with advanced cancers given the chemotherapy/radiation combination had a 47 percent five-year survival rate. With radiation alone, the five-year survival rate was 21 percent; chemotherapy alone had a 34 percent rate.

In those with earlier stages of cancer, combining chemotherapy with radiation only gives a 40 percent five-year survival, which is not as good as chemotherapy alone.

It’s possible the people who had early forms of cancer did worse because they had a rather severe case of the cancer to begin with, and that prompted their physician to recommend radiation, Douillard said. Because the trial was not randomized, he’s unable to determine why the association occurs.

Even so, “this provides very important information for real life,” he said. Douillard plans to reexamine the benefits of chemotherapy and radiation during a randomized trial, which will begin in early 2007 in Europe, he told United Press International.

Lastly, preliminary results out of the Netherlands suggest no benefit for intraarterial versus intravenous chemoradiation in patients with advanced, inoperable head and neck cancer. There were initial reports that intraarterial chemoradiation, which is injected directly into the arteries and travels to the vessel that feeds the tumor, could work better than the conventional intravenous procedure. Researchers thought the treatment would be more concentrated in the tumor, and thus more effective.

But in a 2000 to 2005 randomized study involving 240 patients in five hospitals, the patients with intraarterial therapy lived the same amount of time as the intravenous patients.

“Since the current standard is intravenous radiation, it is to remain the standard of care for advanced cases,” said researcher Dr. Coen Rasch of the Netherlands Cancer Institute in Amsterdam.

In the past, people with inoperable head and neck cancers would die at a rate of 70 percent; now, it’s more like 30 percent, Rasch said.

Renal and skin toxicity was less frequent with the intraarterial therapy, but neurological toxicity was more common using the technique.

Despite the fact intra-arterial offered no clear boon, Rasch speculates those with localized, smaller tumors — those that are connected to one artery — are more responsive to intraarterial therapy. However, this was not the main purpose of the study, and so further research would need to back up this speculation.

“Sometimes a very important study is a negative study,” Lawrence said. “Now we know from this carefully carried-out study that we should focus our efforts elsewhere.”