A rare form of breast cancer could be linked to the presence of silicone or saline implants used in breast enhancement surgery, according to the Food and Drug Administration, which announced recently it would investigate any possible connection.

Although anaplastic large-cell lymphoma (ALCL) is slightly more common in lymph nodes and the skin, but is still quite rare, the FDA said, and incidence in breast tissue is even less common. The administration has asked physicians around the country to contribute to a database of ALCL cases, in order to study any patterns that may arise.

In a review of 13 years of scientific literature, 34 cases of ALCL were seen in women with both silicone and saline breast implants, the FDA said. A total of 60 cases worldwide were discovered, according to the administration.

While there is no conclusive evidence to support such a connection, the FDA urges women with breast implants to monitor them closely and to make sure they contact a physician if they notice anything unusual.