Medical diagnostic firm PerkinElmer Inc faces a federal investigation into its role in an alleged Medicare fraud involving tens of thousands of unnecessary genetic cancer tests, according to three sources with knowledge of the probe and documents reviewed by Reuters.

The firm conducted the tests now under scrutiny over 18 months, earning millions of dollars, according to one of those sources and three others familiar with the company’s lab operations.

Investigators are probing whether Massachusetts-based PerkinElmer enabled a scheme by some its laboratory clients, two of which the government previously has charged in connection with alleged Medicare fraud, said the three sources with knowledge of the probe.

PerkinElmer ran high volumes of tests for those clients. Investigators are focused on whether the firm knew – or should have known – that the tests were not medically necessary and that its clients were billing them to the government program for the elderly and disabled, those three sources said.

Such tests determine if patients are at risk of developing hereditary diseases, such as breast or colorectal cancer. Medicare covers the screenings if a patient’s physician deems them necessary, often because of a personal or family history of hereditary cancers.

The tests sent to PerkinElmer raised red flags among some company employees because the patients often didn’t fit the typical profile for testing and few results showed a cancer risk, according to the three sources familiar with the company’s operations.

A spokeswoman for PerkinElmer, Fara Goldberg, did not answer detailed questions from Reuters but said in a statement that the company was not aware of any fraud or abusive practice by PerkinElmer or any employee, and that it had “not been notified of any actual or alleged wrongdoing by any government authority.”

The company said it supports government efforts to identify and prevent abuse in genetic testing, and that it would cooperate with such efforts “as appropriate.”

Madhuri Hegde, a chief scientist for the company’s genetic testing unit, is also under investigation because of her role in establishing business relationships with the lab clients charged in the Medicare fraud schemes, according to two people familiar with the probe and records of the investigation reviewed by Reuters.

Source: Reuters