Allergan Implants and Breast Implant Associated Anaplastic Large Cell Lymphoma (BIA-ALCL)
After an implant has been placed under the breast tissue the body begins a healing process and creates a thin layer of scar tissue around the implant. We call this layer the ‘capsule’. The capsule is your body’s natural barrier to the presence of a foreign body. Capsules form around all implanted devices, such as pacemakers, replacement joints, and grafts. Capsules contain a number of cells from the immune system. The commonest is the fibroblast that makes the scar. But there are also white blood cells in there too. Breast Implant Associated Anaplastic Large Cell Lymphoma (BIA-ALCL) is a rare lymphoma of the white blood cells in the tissue that can sometimes form in this layer of tissue adjacent to the implant- when it forms it therefore begins in the ‘capsule tissue’. It is reported to be extremely rare with smooth shelled implants (actually no occurrences have ever been reported world-wide where this has been the only type of implant used as of December 2018. This includes data going back since the first case report of this rare disease in 1997). Some implants from different manufactures have different types of texture, that have been created using different techniques. For example, the texture on Mentor textured implants is sometimes referred to as a micro texture although there have been no specific studies prior to 2018 that have analysed and stratified texturing scientifically. But there do seem to be differences emerging in the association of this rare lymphoma with some of the different types of texturing. But as the ALCL type of lymphoma is rare there are some implant manufactures that have never been associated with a case, perhaps simply because their implants represent such a small fraction of the global implant market.
The Mentor Siltex texture (sometimes referred to as a microtexure by the manufacturer’s UK representatives) has had lower estimated rates of ALCL reported in 2017 compared to the Allergan Biocell texture. For Siltex the rate in a 2017 study published in Australia (Loch-Wilkinson) is thought to be between 1 in 30,000 to 1 in 60,000. The rate could be higher than this but it is probably less than a 1 in 1000 level of risk. Data will clarify this over time. For the macro textured group (e.g. Allergan Biocell macro texture) the risk estimate may be 1 in 1000 to 1 in 10,000. It could be more frequent than this and future date collection will help to clarify this.