MUHC breast cancer trial shows promise
A medical team at the McGill University Health Centre is reporting far fewer radiation side effects in breast-cancer patients using an experimental therapy that appears to produce the same clinical results as conventional radiotherapy.
The therapy is aimed at the five to 10 per cent of breast-cancer patients whose malignancy has not spread beyond the primary tumour site to the lymph nodes or other organs. In such cases, a woman undergoes a lumpectomy followed by four to six weeks of radiotherapy.
But standard radiotherapy can produce skin burns to the breast, and if the tumour is on the left side, the heart and lung can also be exposed to some radiation.
The MUHC group, however, uses a highly targeted dose of radiation that’s delivered only once — and in just 30 minutes. Known as intraoperative radiation therapy, the doctors use a wand-like instrument called the Intrabeam to zap the surgical cavity immediately following the lumpectomy.
“The results have been great,” said Dr. Tarek Hijal, chief of radiation oncology at the MUHC. “Since 2013, 21 women have received the Intrabeam treatment as part of this MUHC clinical trial, each one of them with positive patient satisfaction and few side effects.”
Janet Pegg is one of those patients, and on Friday, she returned to the MUHC for an appointment with her doctor. The 69-year-old Notre-Dame-de-l’Île-Perrot resident learned she had breast cancer on Feb. 28, and less than three weeks later, she underwent the Intrabeam treatment at the Royal Victoria Hospital.
“I’m feeling fantastic, tired but fantastic,” Pegg said.
When doctors told her she was a candidate for the clinical trial, she thought that the idea of a one-time treatment of radiation “sounded too good to be true.”
Since Pegg takes care of her intellectually-disabled 47-year-old daughter at home, she said it would have been virtually impossible for her to have to travel into the city for 20 to 30 standard radiotherapy sessions.
“(The treatment) has made the world of difference, not just for me, but for my daughter as well,” Pegg added.
A previous clinical trial in Europe compared the efficacy of the Intrabeam with standard radiotherapy, and found that the risk of a recurrence of localized breast cancer was 3.3 per cent with the experimental treatment compared with 1.3 per cent with conventional therapy.
Hijal, however, said he expects the MUHC study — the first of its kind in Quebec — will show superior clinical results because doctors are more discriminating in selecting the patients who will benefit the most from the Intrabeam. In addition, the MUHC team is using the Intrabeam right after a lumpectomy, as opposed to other doctors who used it after a second operation.
The MUHC team has innovated in other ways as well. Dr. Jan Seuntjens, director of medical physics at the MUHC, developed with his colleagues a group of sizing instruments that are used before the Intrabeam wand is inserted into the surgical cavity. Hijal estimated that the Intrabeam treatment would save $1,000 per patient over standard radiotherapy, while sparing patients harmful side effects.
Breast cancer is the most common cancer among Canadian women. It’s estimated that 5,000 women will die from the disease this year, according to the Canadian Cancer Society.