Year of Grant: 2017

Location: Switzerland

The removal of all lymph nodes in the armpit (Axilla), a procedure called conventional axillary dissection (ALND), has been standard care for all patients with breast cancer for almost a century. In the nineties, the selective removal of the first few lymph nodes, the sentinel lymph node procedure  was introduced in clinical practice. Today, ALND is still performed for many women with breast cancer that has spreaded to the nodes. All too often, however, many unaffected nodes are removed in women that have a positive sentinel node or otherwise proven disease in the axilla.

This unnecessary extent of surgery causes high morbidity, lymphedema (swelling of the arm due to impaired lymphatic drainage), impairment of shoulder mobility, sensation disorders and chronic pain in as much as

one third of all women.

With the ability to precisely localize affected lymph nodes under imaging guidance, the radical concept of ALND needs to be re-evaluated. Targeted axillary dissection (TAD) is a new technique that has recently been developed for patients with initially positive nodes undergoing systemic treatment before surgery. It combines the selective removal of nodes that are localized under imaging guidance with the sentinel procedure and therefore allows the targeted removal of lymph nodes. It is currently used to show that the cancer has fully responded to systemic treatment in the nodes under the microscope and that conventional ALND is therefore not necessary.

The TAXIS trial intends to prove the use of TAD as a tailored procedure to avoid surgical overtreatment by selectively removing the lymph nodes that are affected by the cancer, thereby sparing many women the unnecessary complications of ALND. It is another important step toward de-escalation

of surgery in the era of personalized medicine.

This large phase III multicenter trial will be performed in an academic way within the national SAKK network of breast centers and through international collaboration with the International Breast Cancer Study

Group (IBCSG), The Austrian Breast and Colorectal Cancer Study Group

and major centers in Portugal and Spain. An overall sample size of 1,500 patients will be accrued during a 5-year period. From these, 750 patients

will be accrued by 25 sites in Switzerland.

TAXIS has a strong potential to provide an immediate benefit for the patients in the experimental arm during the trial by sparing them the morbidity of ALND. In the medium term, the results are expected to have an important impact on current international guidelines by de-escalating axillary surgery. In Switzerland alone, about 1,000 ALND procedures are still performed every year, and it is estimated that TAD can spare 20% of those patients significant long-term morbidity.