Doctors nationwide are still using a gynecological tool months after the U.S. Food and Drug Administration warned that it can spread undetected cancer, demonstrating the limits of the regulator's reach into clinical practice.

Since the FDA warning in April, Johnson & Johnson pulled the device called a laparoscopic power morcellator from the market; many hospitals, such as Boston's Brigham and Women's Hospital and Philadelphia's Temple University Hospital, put moratoriums on the tool; and some regional insurers stopped covering its use.

Still, some gynecologists continue to employ morcellators to remove common benign uterine growths known as fibroids, often in minimally invasive hysterectomies. The tool slices tissue into fragments so it can be removed through small incisions, but the procedure can leave bits of tissue behind that can continue to grow and spread, whether benign or unexpectedly malignant.

These doctors say they believe the risks of unknown cancer have been overblown and the government shouldn't interfere with patient treatment.

"It is none of their business," said Jeffrey Thurston, 58, a Dallas gynecologist who has practiced for three decades and said he performs 80 percent of his hysterectomies with a morcellator.

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