Minimally Invasive Surgery for Cervical Cancer Poses Higher Risk of Death

Two recent studies of survival rates in women with early stage cervical cancer show that opting for minimally invasive surgery is associated with a significantly higher chance of dying from the disease. According to an article published last week in the Houston Chronicle, the studies compared survival rates in women who opted for an “open” hysterectomy — the traditional approach — and those who underwent laparoscopic removal of the uterus and ovaries. In the latter procedure, the surgeon uses only three or four small incisions versus the much larger incision used in the open technique.

Both studies were reported in the New England Journal of Medicine and showed remarkably similar results. The first, led by Dr. Pedro Ramirez of the University of Texas MD Anderson Cancer Center, showed a four times greater risk of death in women who underwent minimally invasive hysterectomy.

The second study was a collaboration between researchers at MD Anderson and Harvard, Columbia and Northwestern Universities. It analyzed data on nearly 2,500 women who underwent a radical hysterectomy for cervical cancer stages 1A2 or 1B1 (early stage cervical cancer) between 2010 and 2013. In this sample, the 4-year mortality in women who had minimally invasive surgery was 9.1 percent compared to 5.3 percent in those who had an open procedure. These numbers translate to an increased risk of dying of about 65 percent.

The results startled the researchers, who expected that minimally invasive surgery would be as safe if not safer than open procedures. Further, since the findings were unexpected, they have no explanation as to why they exist. “[The study] was never designed to determine what the cause of this inferiority is because we didn’t think there would be an inferiority,” Dr. Ramirez said.

A Standard of Care

Prior to 1992, virtually all hysterectomies performed for cervical cancer were done using an open surgical technique. However, during the early 1990s, doctors began using minimally invasive laparoscopic surgery to treat cancers of all kinds, with generally favorable results. Minimally invasive surgery is associated with less blood loss, lower infection risk, shorter hospitalizations and fewer postoperative complications than open surgical techniques. What’s more, prior studies of survival rates in patients undergoing minimally invasive surgery for other cancers showed no increased risk of death in those treated with the less invasive technique.

Many women who have minimally invasive surgery for cervical cancer have recurrences requiring treatment with chemotherapy or other drugs
Credit: cancer.gov

Thus, by 2006, minimally invasive radical hysterectomy for early stage cervical cancer became the standard of care. Between 2006 and 2010, the use of the procedure increased from 1.8 percent to 31.1 percent. This coincides with the period during which survival rates in cervical cancer, which had been improving steadily in recent years, began to show a decline of about 0.8 percent per year, according to Dr. Alejandro Rauh-Hain, the principal investigator of the second study

Like Dr. Ramirez, Rauh-Hain was startled by the results. “We expected to find minimally invasive surgery was safe,” he said in a statement to the Houston Chronicle.

No Good Explanation

Again, because both studies were designed to detect outcomes, the researchers have no good explanation as to why these large disparities exist. One possibility is that techniques used during minimally invasive surgery inadvertently causes the spread of cancer cells. In an editorial accompanying the report, Dr. Amanda Fader also cites the interesting fact that cancer recurrences and deaths were clustered at 14 of 33 cancer centers studied, raising the possibility that variations in patient populations or specific surgical techniques contributed to the results.

Nevertheless, Fader warned patients and their doctors to heed the results. “Until further details are known,” she wrote,“surgeons should proceed cautiously, counsel their patients regarding these collective study results, and assess each woman’s individual risks and benefits with respect to minimally invasive as compared with open radical hysterectomy.”