One option for women with a proven BRCA1/2 mutation is to choose screening “with the main objective to identify ovarian cancer in an early stage to improve prognosis and reduce morbidity and mortality,” write Dr. Geertruida H. de Bock and colleagues at the University of Groningen.
However, the effectiveness of such screening “was disappointing,” they report, “with low sensitivities and very low positive predictive values of the different screening modalities. Furthermore, all detected cancers were found in an advanced stage.”
The retrospective studied included 241 women with a pathogenic BRCA1 or BRCA2 mutation who underwent screening at least one time between 1995 and 2006.
The screenings, which started at age 35 years or 5 years earlier than the youngest age at diagnosis of ovarian cancer in the family, involved annual bimanual pelvic examination, transvaginal ultrasound, and measurements of serum CA125.
During a total of 470 screening visits, three ovarian cancers were detected, all in BRCA1 mutation carriers. All three were in an advanced stage (FIGO stage IIIc).
The positive predictive value was 20% for pelvic examination, 33% for transvaginal ultrasound, and 6% for CA125 estimation alone; results were little better when all three screening modalities were combined, the authors note. The negative predictive values were above 99%, indicating that a negative test almost always excluded cancer.
“At this time,” Dr. de Bock and colleagues advise, “prophylactic bilateral salpingo-oophorectomy from age 35-40 for BRCA1 carriers and from age 40-45 for BRCA2 carriers is the only effective strategy, as it reduces the risk of ovarian cancer by 96% and may also protect against breast cancer with a risk reduction up to 53% when performed in premenopausal women.”
They add, “For women who still want to opt for screening, a more effective screening strategy needs to be designed.”
Int J Cancer 2009;124:919-923.