Additional, Specialized Radiation Not Necessary for Some Women After Mastectomy

CHICAGO, Nov. 2 /PRNewswire-USNewswire/ -- After mastectomy, breast cancer
patients who receive radiation treatment to the lymph nodes located behind the
breast bone do not live longer than those who do not receive radiation to this
hard-to-treat area, according to a randomized 10-year study presented at the
plenary session, November 2, 2009, at the 51st Annual Meeting of the American
Society for Radiation Oncology (ASTRO).

Breast cancer that is located in an internal, central location in the breast
area, and larger tumors that have spread to the lymph nodes located under the
arm (axillary) and just above the collar bone (supraclavicular), are more
likely to spread to the internal mammary lymph nodes that are located behind
the breast bone.

The type of external beam radiation treatment used to treat these patients is
called internal mammary chain radiation treatment, or IMC-RT. It is
challenging to deliver the proper dose of radiation to the internal mammary
chain because it is hard to define its exact location and to protect critical
organs, such as the heart and lung.

"This is the first study that answers the important question of whether
radiation to the internal mammary chain lymph nodes benefit these patients
after 10 years of follow-up," Pascale Romestaing, M.D., lead author of the
study and a radiation oncologist at Centre de Radiotherapie Mermoz in Lyon,
France, said. "Our findings clearly show that it does not affect overall
survival. These women still need radiation treatments -- just not additional
radiation to these specialized cells."

During external beam radiation therapy, a beam (or multiple beams) of
radiation is directed through the skin to the cancer and the immediate
surrounding area in order to destroy the main tumor and any nearby cancer
cells. The treatments are outpatient and generally painless, much like
receiving an X-ray.

The multi-center randomized trial involved 1,334 women newly-diagnosed with
stage 1 or 2 breast cancer who had undergone a mastectomy, or surgery to
remove a breast. Patients had either cancer that had spread to the axillary
lymph nodes or their original tumor was in an internal, central location in
the breast area. While all patients received radiation to the chest wall and
supraclavicular lymph nodes, one-half of the patients were randomized to also
receive the specialized IMC radiation treatment.

After 10 years, researchers found no significant differences in survival rates
between the group who received IMC radiation treatment (63 percent) and those
who did not (60 percent). The study also found no differences in survival for
patients in the study who were analyzed in subgroups. These groups included
whether or not their cancer had spread to their lymph nodes, where their
original tumor was located, and whether they also underwent chemotherapy or
hormone therapy at the same time they had radiation treatment.

For more information on radiation therapy for breast cancer, visit
www.rtanswers.org.

The abstract, "Ten Years Results of a Randomized Trial of Internal Mammary
Chain Irradiation (imc-rt) after Mastectomy," was presented at the plenary
session at 2:15 p.m. on Monday, November 2, 2009. To speak to the lead author
of the study, Pascale Romestaing, M.D., please call Beth Bukata or Nicole
Napoli November 1-4, 2009, in the ASTRO Press Room at McCormick Place West at
312-791-7005 or 312-791-7006. You may also e-mail them at bethb@astro.org or
nicolen@astro.org.

SOURCE American Society for Radiation Oncology

Beth Bukata, bethb@astro.org, or Nicole Napoli, nicolen@astro.org,
800-962-7876, Press Room Phone: Nov. 1-4, +1-312-791-7005, or +1-312-791-7006,
After Hours: +1-703-474-9040