Study Finds Breast Cancer Survival Improving Despite Recurrence (dateline June 7, 2004)
More women who experience a recurrence of breast cancer after initial treatment<are surviving the disease, according to the results of a recent study conducted by the M.D. Anderson Cancer Center. The report shows that since 1974, the survival rate from breast cancer recurrences has increased approximately 1% each year. The researchers attribute the improvement in survival to better treatment strategies; in particular, more effective drug therapies.
The American Cancer Society estimates that in 2004, 215,990 women in the United States will be diagnosed with invasive breast cancer. Approximately 40,110 of these women will die from the disease this year. There are over two million women living in the U.S. who have been treated for breast cancer.
To study breast cancer trends over the past few decades, Sharon H. Giordano, M.D., and her team from M. D. Anderson Cancer Center in Houston, Texas studied survival rates of 834 women who experienced a recurrence of breast cancer between November 1974 and December 2000. Patients were divided into five groups based on year of breast cancer recurrence: 1974-1979, 1980-1984, 1985-1989, 1990-1994 and 1995-2000. Survival was compared across the five groups.
Results of the analysis showed that breast cancer survival among the women who experienced recurrences of the disease improved approximately 1% each year from 1974 to 2000. In the study, women diagnosed with breast cancer recurrences in more recent years were more likely to survive than women diagnosed in the seventies, for example. Other factors that predicted longer periods of survival after breast cancer recurrence included smaller initial tumor size, earlier stage of the disease, fewer lymph nodes involved, longer disease-free interval, estrogen receptor-positive tumors, and the site of the disease recurrence.
Women with breast cancer recurrences who were part of the earlier periods of the study were more likely to experience recurrences in the liver and lungs, compared to more recent diagnoses, many of which occurred in the lymph nodes. Despite these differences, the researchers attribute the overall trend in improved breast cancer survival to better treatment. In particular, Dr. Giordano and colleagues say drug therapies have dramatically improved in recent years.
There are several different classes of drugs used to treat breast cancer. These include: SERMS (selective estrogen-receptor modulators), aromatase inhibitors, biologic response modifiers, and hormonal therapies. Specific drugs used to treat breast cancer include:
*Generic drug names are shown in parentheses.
The researchers say that further studies are needed to conclusively determine whether the improvements in drug therapy are responsible for improvements in breast cancer survival. In the meantime, they are encouraged by this promising trend.