In a nutshell
This study evaluated if strategies to prevent cancer recurrence are associated with prolonged survival 15 years after treatment. Their main findings were that postoperative radiation managed to prevent cancer recurrence and was associated with higher rates of long-term survival.
Some background
Early breast cancer is often treated surgically, with or without complementary radiation. This management strategy strives to prevent local recurrence of the cancer. Local breast cancer is managed by one of two main surgical methods: Lumpectomy (removal of only the cancerous tumor) or Mastectomy (the removal of the entire breast with or without surrounding lymph nodes and muscles). The purpose of postoperative radiation is to destroy residual cancer cells not removed by surgery. However, the use of radiotherapy remains controversial to this day.
Methods & findings
The present study (performed 2005) used data from 78 clinical trials involving a total of 48,000 women. These trials compared common therapies for local breast cancer:
¨ Surgery with or without radiation
¨ Lumpectomy compared to mastectomy
¨ Mastectomy compared to radiation
The researchers then combined the results to evaluate the benefits of radiation in the short- and long-term.
Results showed that radiotherapy reduced the 15-year breast cancer risk of death by 5.4%, irrespective of the type of surgery. The 5-year risk of recurrence was reduced by 19% after lumpectomy (7300 women) and by 17% following mastectomy (8500) in women with involved lymph nodes. Radiotherapy produced similar reductions in local recurrence in all women (irrespective of age or tumor characteristics) and in all major trials comparing surgery with or without radiation. Women who had larger and higher-grade tumors that spread to lymph nodes experienced the greatest benefits from radiotherapy.
The bottom line
In summary, this large-scale study showed that combining surgery and radiotherapy provides a long-term survival benefit.
The fine print
A limitation of this analysis is the omission of the relationship between treatment era and overall survival. The far superior technology today may vastly improve outcomes relative to earlier decades.
Published By :
The Lancet
Date :
Dec 17, 2005
