Radiotherapy to internal mammary and medial supraclavicular lymph nodes improves survival
(dailyRx News) Researchers and scientists continue to find new and better ways of treating breast cancer. And may of these improvements not only help patients live longer, but are gentler on the patient and improve quality of life during treatment.
Targeting radiation to the internal breast and upper collarbone lymph nodesimproved survival in breast cancer patients without causing serious side effects.
This technique, a new study found, is more effective than directing radiation to the breast and chest wall only, the researchers learned.
Philip Poortmans, a radiation oncologist from the Institute Verbeeten in Tilburg, The Netherlands, and a member of the EORTC Radiation Oncology and Breast Cancer Groups, led the international clinical trial.
When cancer spreads to the lymph nodes—a key part of the immune system that fights off invaders—the odds that the cancer will spread (metastasize) to other areas of the body increase.
In breast cancer, the lymph nodes in the armpit (axilla) are usually involved. Treatment involves either surgery or radiation.
More uncommonly, the cancer drains to internal mammary (IM) lymph nodes which are located behind the breast bone and also above the collar bone, known as the medial supraclavicular (MS) nodes.
Radiation has not been used to treat these lymph nodes because physicians didn’t know what the radiation might do to that area or what toxic side effects it might cause.
The research team recruited 4004 breast cancer patients between 1996 and 2004 from 43 centers around the world.
Participants were randomly assigned to receive either 50 units (50 Gy) of radiation to the IM-MS area in 25 units or standard radiation therapy.
After a median follow-up of 10 years:
82.3 percent of the participants who received IM-MS radiotherapy were still alive compared to 80.7 percent of those who did not receive the targeted radiation treatment.
Disease free survival, meaning there were no signs of the breast cancer, was 72.1 percent among the IM-MS group and 69.1 percent for those who received standard radiotherapy.
In the IM-MS group, 382 patients died vs. 429 patients in the no IM-MS group.
No lethal side effects were observed.
The research team plans to follow these patients for an additional 10 years.
“Anything that will increase local control and survival in women with breast cancer without increasing toxicity is worth pursuing,” Alexis Harvey, MD, medical director of 21st Century Oncology New Jersey Region, told dailyRx News.
"With IMRT [intensity-modulated radiation therapy], there is tremendous sparing of normal tissues that traditionally would have been irradiated, while treating the MS/IM nodes, and the outcomes in this study provide evidence justifying the need for nodal irradiation in selected patients,” said Dr. Harvey, who was not involved in the study.
Results of this study were presented at the 2013 European Cancer Congress (ECC2013). Before publication in a peer-reviewed journal, all research is considered preliminary.
No conflicts of interest were disclosed.