The fallopian tubes don’t look like much. Two slender ducts, each roughly 10 centimetres long, connecting ovaries to uterus. For decades, surgeons removing someone’s uterus or performing tubal ligation would leave them in place. Why bother taking them out?

Turns out, there was a very good reason.

In 2010, a team of Canadian researchers made British Columbia the first place in the world to offer something called opportunistic salpingectomy, OS for short. The concept is straightforward, almost absurdly so: when you’re already doing pelvic surgery, remove the fallopian tubes too. Keep the ovaries (they produce essential hormones), but take the tubes.

The logic was simple. Scientists had discovered that most ovarian cancers don’t actually start in the ovaries. They begin in the fallopian tubes.

Now, after more than a decade of follow-up, the numbers are in. And they’re remarkable. People who had their fallopian tubes removed during routine gynaecological surgery were 78 per cent less likely to develop serous ovarian cancer, the most common and lethal form of the disease, compared with those who had similar operations but kept their tubes. The findings, published today in JAMA Network Open, come from the Ovarian Cancer Observatory, an international collaboration led by researchers at the University of British Columbia.

“This study clearly demonstrates that removing the fallopian tubes as an add-on during routine surgery can help prevent the most lethal type of ovarian cancer,” says Gillian Hanley, an associate professor of obstetrics and gynaecology at UBC and co-senior author of the study. “It shows how this relatively simple change in surgical practice can have a profound and life-saving impact.”

The scale of data is substantial. The team analyzed health records for more than 85,000 people in BC who underwent gynaecological surgeries between 2008 and 2020. Roughly half had OS, half didn’t. The researchers then tracked who developed ovarian cancer.

Ovarian cancer is a brutal disease. About 3,100 Canadians are diagnosed each year, and around 2,000 die from it. There’s no reliable screening test, which means most cases get caught late, when treatment options are limited and survival rates plummet. Prevention, then, isn’t just preferable. It’s essential.

The OS approach was initially developed by Dianne Miller, an associate professor emerita at UBC and gynaecologic oncologist who co-founded BC’s multidisciplinary ovarian cancer research team, OVCARE. Her philosophy is straightforward: “If there is one thing better than curing cancer it’s never getting the cancer in the first place.”

The new study goes further than previous research in two key ways. First, it quantifies exactly how much protection OS offers against serous ovarian cancer specifically, not just ovarian cancer generally. Second, the researchers collected data from pathology laboratories worldwide to see what types of ovarian cancers occurred in people without fallopian tubes.

That second finding is perhaps even more striking than the first. Of the 26 ovarian carcinomas identified in people who’d had their tubes removed, only 6 were high-grade serous carcinomas, the aggressive subtype that accounts for roughly 70 per cent of all ovarian cancers. That’s just 23 per cent. In a historical cohort of people with intact fallopian tubes, HGSC represented 68 per cent of cases.

The implication? OS doesn’t just reduce overall ovarian cancer risk. It specifically targets the deadliest form.

The procedure has proven safe in multiple studies. It doesn’t appear to trigger early menopause. The ovaries remain, after all, and keep producing hormones. Previous research showed it’s cost-effective for health systems. And crucially, it doesn’t add significant time or risk to surgeries people were already having.

Adoption in BC has been substantial. Roughly 80 per cent of hysterectomies and tubal ligation procedures in the province now include fallopian tube removal. Globally, professional medical organizations in 24 countries recommend OS as a prevention strategy. The Society of Obstetrics and Gynaecology of Canada issued guidance back in 2015.

“This is the culmination of more than a decade of work that started here in B.C.,” says David Huntsman, professor of pathology and laboratory medicine at UBC and a distinguished scientist at BC Cancer, who co-led the study. “The impact of OS that we report is even greater than we expected.”

BC recently became the first Canadian province to expand OS beyond gynaecological surgeons, training general and urologic surgeons to offer the procedure during abdominal and pelvic operations. The move could extend prevention to thousands more people.

But global uptake remains incomplete. Many jurisdictions haven’t yet adopted OS recommendations. Some surgeons may be unaware of the evidence; others might not have received training. Huntsman is direct about the stakes: “Our hope is that more clinicians will adopt this proven approach, which has the potential to save countless lives. Not offering this surgical add-on may leave patients unnecessarily vulnerable to this cancer.”

The study has limitations. Many participants underwent surgery well below the typical age for ovarian cancer, which meant relatively few cases occurred overall – just over 20 in the comparison group, fewer than five in the OS group. (Privacy rules prevent exact reporting of small numbers.) That limited the researchers’ ability to control for every possible confounding factor in their statistical models.

Still, the team ran a clever check for selection bias. They analyzed breast cancer rates in the same cohorts. If the groups differed in some fundamental way that affected cancer risk, you’d expect to see different breast cancer rates too. But they didn’t. The hazard ratio for breast cancer was essentially 1.0 – no difference.

The findings underscore something the research community has suspected for years: the fallopian tubes are not neutral bystanders in ovarian cancer. For many people, they’re where the trouble begins.

Simple interventions are easy to overlook precisely because they’re simple. Removing fallopian tubes during planned surgery seems almost too straightforward to have such dramatic impact. But sometimes the most effective solutions are the ones hiding in plain sight – small changes to existing practice that, implemented widely, could prevent thousands of cancers each year.

The question now isn’t whether OS works. The data are clear. The question is how quickly the rest of the world catches up to what BC started more than a decade ago.

Study link: https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2844597