Finally, the new recommendations are currently based on a hypothesis, not on evidence. "There are other situations in our history in medicine where physicians really believed something very strongly and proceeded with limited information," he noted, citing by way of example the use of diethylstilbestrol in the 1940s and 1950s to prevent miscarriage, and its subsequent linkage to cancer. "We need to be sure that we get the evidence. I believe that we need to evaluate this in some form of clinical trial."
Should salpingectomy prove to be effective and adequately safe for preventing ovarian cancer, it would constitute a major turning point in a disease that still has a poor prognosis, according to Dr. Rosen.
To be sure, treatments have improved steadily over the past 25 years, prolonging life and improving its quality. "We can continue to expect improvements, but I think they are going to be gradual and they are going to be small," he said. "I don’t think anybody would say that there are any home runs out there right now."
Efforts to detect the cancer early through screening have thus far not panned out. Three large screening studies were initiated in 1985-2001, one each in the United Kingdom, Japan, and the United States.
Results from the last – the PLCO (Prostate, Lung, Colorectal, and Ovarian) trial, which tested screening with cancer antigen 125 (CA 125) and transvaginal ultrasound – were recently reported (JAMA 2011;305:2295-303). They showed that 20 surgeries had to be performed to detect one cancer, and the rate of major complications was 20% among patients who underwent surgery. And at the end of the day, there was no reduction in ovarian cancer mortality.
"This is a big study, it is very well done, [and] it has a very long follow-up," Dr. Rosen commented. "And I think this pretty much conclusively says that ultrasound and CA 125 [screening] just don’t work." Results of the U.K. study, which is using a different, serial multimodality approach to screening, are expected in the 2014 timeframe.
Prevention efforts up to this point have been limited to birth control pills and to BRCA testing with prophylactic surgery for carriers, but this group makes up only about a tenth of all patients with ovarian cancer, he noted.
Dr. Rosen said he had no relevant financial disclosures.