Second primary ovarian cancer among women diagnosed previously with cancer

This study assessed the risk of second primary ovarian cancer among United States women diagnosed previously with invasive cancer. We analyzed data fr om cancer registries participating in the Surveillance, Epidemiology, and E nd Results program for women diagnosed with invasive cancer between 1973 an d 1996. We calculated the risk [observed (O)/expected numbers (E)] of secon d primary ovarian cancer by cancer site and age at diagnosis of first prima ry cancer (<50 years and <greater than or equal to>50 years), race (all, wh ite, and black), and years since first cancer (0-4, 5-9, 10-14, and 15-24 y ears). Statistical tests and 95% confidence intervals (CI) assumed a Poisso n distribution. A significantly increased risk of ovarian cancer was found for women who were aged <50 years at diagnosis with melanoma (O/E = 3.5, 95 % CI 2.1-5.5) or cancer of the breast (O/E 6.0, 95% CI = 4.9-7.2), cervix ( O/E = 4.2, 95% CI 2.6-6.3), corpus uteri (O/E = 11.9, 95% CI = 7.3-18.4), c olon (O/E = 17.9, 95 % CI = 11.1-27.3), or ovary (O/E = 4.9, 95 % CI = 2.7- 8.2). No increased risk was found for women aged <greater than or equal to> 50 years. Ovarian cancer risk remained elevated after these first primary c ancers 5-9 years after diagnosis; for breast and colon cancer, risk remaine d elevated 15-24 years after diagnosis. Women <50 years at diagnosis with m elanoma or cancer of the cervix, corpus uteri, ovary, rectum, or lung and b ronchus were at a decreased risk for second primary ovarian cancer. Ovarian cancer risk is higher than expected for women who were diagnosed with cert ain types of cancer at <50 years of age.