According to national treatment guidelines, older women who suffer from early stage estrogen-driven breast cancer, which has not spread to the lymph nodes, can be treated with lumpectomy and estrogen blockers and does not require radiation.
A new study by Benjamin Smith, MD, of The University of Texas MD Anderson Cancer Center in Houston and his team analyzed data from 7,403 women between the ages of 70 to 79 years who underwent a lumpectomy for this type of breast cancer between 1992 and 2002. The data was obtained from the Surveillance, Epidemiology, and End Results-Medicare database, in which cancer registry data is linked to a master file of Medicare enrollment. The team established that around 88% of the participants received radiation following their lumpectomy.
The team examined follow up data of the participants to establish the women's future outcomes after their breast cancer therapy and discovered that within 10 years after treatment 6.3% of the participants women who had no radiation therapy had to undergo a mastectomy compared with only 3.2% of participants who received radiation after their lumpectomy. Even though the data did not list the reasons for the mastectomy, the most likely reason is recurrence of cancer in the breast.
The team also identified which patient group appeared to gain the most benefit from radiation. The found that whilst women aged between 75 to 79 years with non-high grade tumors, i.e. whose cells look only moderately abnormal under a microscope, did not particularly benefit women from radiation and can therefore probably omit radiation therapy, those with high-grade tumors, i.e. whose cells are very abnormal, seem to gain the most benefit regardless of their age.
Dr. Smith concluded:
"These data are important because they suggest that radiation is likely of some benefit to certain women where national guidelines say that radiation is not needed. Our data could be helpful to women when they decide whether or not to undergo radiation."
Written by Petra Rattue