P&S Journal: Fall 1997, Vol.17, No.3
Removal of Breasts and Ovaries in Women with the BRCA1 Gene
Prophylactic mastectomy and oophorectomy for women who carry the BRCA1 mutation and have a family history of breast and ovarian cancer can prolong life expectancy by approximately 8.5 years, but at a great cost to quality of life, concludes a study by P&S researchers.
The findings were presented in May at the annual meeting of the American Society of Clinical Oncology. The study also concludes that prophylactic surgery is cost-effective compared with the cost of cancer treatments and should be covered by insurance companies.
Dr. Victor R. Grann, director of health outcomes research at Columbia-Presbyterian's Herbert Irving Comprehensive Cancer Center, and colleagues based their findings on survival data from 1.6 million cancer cases covering 10 percent of the U.S. population. Using these data, they developed a decision analysis computer model for a healthy 30-year-old woman who has been diagnosed with the BRCA1 gene and has a family history of breast and ovarian cancer. Women with BRCA1 mutations from high-risk families may have an 85 percent risk of developing breast cancer and a 63 percent risk of developing ovarian cancer by age 70. Dr. Grann's model assesses the effects of a prophylactic oophorectomy, a prophylactic mastectomy with oophorectomy, or surveillance alone on survival time, quality of life, and cost effectiveness.
The study found that a 30-year-old woman with the BRCA1 gene who comes from a high-risk family and has a prophylactic oophorectomy would be expected to live 4.1 years longer than a woman who did not have the procedure. A prophylactic oophorectomy and mastectomy would increase survival by 8.5 years.
The study findings differ from earlier research described in the New England Journal of Medicine in that these results were based on data from only high-risk women with the BRCA1 gene who have at least four first-degree relatives with breast or ovarian cancer.
The researchers also measured the effect of the three options on quality adjusted life years, a common statistical measurement that attempts to measure the impact of disease and treatment on daily happiness, self-image, and physical comfort, for example. They found that a woman living with the physical and emotional effects of having her breasts and ovaries removed at age 30 gained only one quality adjusted life year, compared with a woman who chose not to have a prophylactic procedure. A quality adjusted life year is defined as one year of perfect health.
"These figures show that many women will not gain that much in terms of quality of life by choosing prophylactic surgery over surveillance," says Dr. Grann. "Yes, you can prolong your survival with surgery. Eight years of life is a lot of additional life years. But these are difficult procedures in terms of quality of life for a 30-year-old woman who will have to go through life without breasts or ovaries. The impact on happiness and self-image is the tradeoff. It would be understandable if she wanted to avoid prophylactic surgery."
Finally, the study found prophylactic surgery to be more cost-effective than other related medical treatments, with prophylactic oophorectomy costing $888 per quality adjusted life year and prophylactic oophorectomy and mastectomy costing $4,276 per quality adjusted life year. In contrast, chemotherapy for a 45-year-old with breast cancer that had not spread to her lymph nodes cost $15,400 per quality adjusted life year. Autologous bone marrow transplantation for metastatic breast cancer cost $27,300 per quality adjusted life year.
Dr. Grann concludes that this work is preliminary and notes that new methods of treatment could evolve to make prophylactic surgery obsolete.