Partial-breast irradiation may offer the same benefits in terms of overall survival and reduction of metastases as conventional whole-breast radiation therapy for early-stage breast cancer, according to a study presented Sunday at the 2009 American Society of Clinical Oncology (ASCO) meeting in Orlando, Fla.
Despite their findings, the investigators noted that several additional randomized studies are currently under way, and no recommendations about this approach can be made until they are completed.
"Although more research is necessary, this study suggests that partial-breast irradiation may be safe and feasible for women with early-stage breast cancer because it does not jeopardize patient survival or increase the risk of metastasis," explained lead author Antonis Valachis, MD, associate breast cancer researcher at the Panhellenic Association for Continual Medical Research in Athens, Greece. "Partial-breast irradiation reduces treatment time and radiation exposure to normal tissue, may improve cosmetic results, and is likely to enhance patients' ability to comply with therapy."
Valachis and his colleagues evaluated data on 1,140 women in three clinical trials comparing partial-breast irradiation and traditional whole-breast radiation therapy.
They found that there were no significant differences in overall survival or the development of metastases associated with death (odds ratio 0.912), distant metastasis (odds ratio 0.740) or supraclavicular recurrences (pooled odds ratio 1.415).
However, women who received partial-breast irradiation were twice as likely to experience cancer recurrence in the same breast as the primary tumor and three times more likely to develop cancer in the nearby axillary lymph nodes, according to the researchers. The recurrences had no affect on overall survival, however.
Based on their findings, Valachis and colleagues concluded that partial-breast irradiation does not jeopardize survival and may be used as an alternative to whole-breast radiation. "Nevertheless, the issue of loco-regional recurrence needs to be further addressed," they noted.