Hospital tests powerful heavy-ion breast cancer therapy


A Japanese cancer specialist said Wednesday she has started the world’s first clinical trial of a powerful, nonsurgical, short-term radiation therapy for breast cancer.

The National Institute of Radiological Sciences is experimenting with “heavy ion radiotherapy,” a technique in which a pinpoint beam can be accurately directed at malignant cells, said Kumiko Karasawa, a radiation oncologist and breast cancer specialist.

The new therapy has proved its worth on other types of cancer, including prostate and lung, but has never been used on breast cancer, Kyodo News reported.

The study was launched amid renewed global interest in breast cancer and its treatment after Oscar-winning actress Angelina Jolie revealed earlier this month that she had undergone a preventive double mastectomy.

Heavy ion radiotherapy has proved effective in combating other forms of cancer that have not spread throughout the body, Karasawa said.

“We are able to conduct this trial because we have greater understanding of what types of breast cancer can benefit from this pinpoint treatment,” Karasawa said in an interview.

Development of a medical apparatus that keeps soft breast tissue immobile for this treatment has also helped, she added.

Japan is a leader in the technology used in the treatment and is home to three of the world’s six medical centers that have the gigantic ¥10 billion facilities.

Conventional radiotherapy makes use of X-rays and gamma rays that are most potent at the body’s surface but weaken as they travel deeper into tissue. Heavy ion particle beams maintain their strength to a much greater depth.

In the trial, Karasawa will treat 20 patients 60 or older who have small tumors that have not yet spread. The patients will go through an hour of daily therapy for four days.

Conventional radiation therapy can last for months.

The trial will track the patients for five years to assess the outcome, she said.

“Ultimately, this could provide an option for patients who do not want surgery and who cannot go through (common radiation therapy) requiring regular visits to clinics for months,” Karasawa said.

Thanks to its modern medical system, Japan has a good track record with breast cancer, giving patients a five-year survival rate of 90 percent.

Developing localized and less invasive medical treatments is becoming increasingly important as the nation tries to reduce the physical burden on the rapidly aging society, the institute said in a statement.