A team of international researchers investigated the possible link between breast implants and a form of lymphoma that may develop in tumors at a later stage.

In a study published in Mutation Research, researchers concluded that breast implants can cause a subtype of a rare, malignant lymphoma known as anaplastic large cell lymphoma (ALCL).

The likelihood of developing ALCL after undergoing breast surgery remains extremely rare, with between one and six recorded instances for every three million breast implant surgeries. 

ALCL is typically found in the lymph nodes as well as skin, lung, liver and soft tissue. Patients who developed ALCL in the breast region almost always had breast surgery, with the tumors occurring in scar tissue around the implant, according to a news release on the study.

The researchers investigated 71 cases of ALCL in which breast implants were suspected to be the cause.

There are two subtypes of ALCL, with one producing an abnormal form of the protein anaplastic lymphoma kinase (ALK), and the other not expressing ALK in tumor cells at all. Patients with ALK-positive lymphoma have better survival rates. ALK-negative cancer in patients appears to be more aggressive.

But researchers discovered a third type of ALCL in implant-related cases that does not express ALK, and patients have good survival rates. 

“This is a previously unrecognized, new subtype,” study author Lukas Kenner, aViennese pathologist, said in the news release.

“We must now determine the exact cause behind its occurrence,” Kenner said.

The research team is planning further studies to pinpoint the direct cause behind why implants can cause lymphoma.