February 1, 2006

Radiation Cuts Risk of Breast Cancer Return

NEW YORK (Reuters Health) - Use of radiation therapy reduces the risk that a breast cancer removed with breast-conserving surgery will return, according to a report in the medical journal Cancer. A surgical specimen with no evidence that cancer was left behind is tied to a reduced risk of recurrence as well.

The results also show that cancer recurrence is an important determinant of subsequent spread to distant sites in the body.

The study involved 1,901 women with early breast cancer who were treated with breast-conserving surgery at one of 18 Japanese centers between 1986 and 1993.

The 10-year overall survival rate was 84 percent, lead author Dr. Yoshifumi Komoike, from Osaka Medical Center in Japan, and colleagues note. The percentage of patients who were alive at 10 years with no evidence of cancer was slightly lower -- 78 percent.

The cancer recurrence rate in patients who had radiation after surgery was 8.5 percent, compared with 17.2 percent among those who did not undergo radiation treatment, the findings indicate. Older age and surgical evidence that the entire tumor was removed were also linked to a decreased risk of recurrence.

Women with cancer recurrence were nearly four times more likely to develop distant cancer spread or "metastases" than their peers without recurrence, the investigators report. In women with cancer recurrence, lymph node involvement and a short period of time to recurrence both raised the risk of distant metastases.

Further studies are needed to determine if breast cancer recurrence causes or is just associated with distant metastases, the researchers conclude.

SOURCE: Cancer, January 1, 2006.