Intraoperative radiation therapy (IORT) with the IntraBeam

With normal breast-conserving surgery of a breast carcinoma, repeated radiotherapy of the entire breast usually follows. At the end of the radiotherapy, the radiation fields are reduced to “boost fields” encompassing the previous, smaller tumour region. This standard treatment with the linear accelerator takes around six weeks.

In our clinics, this therapy is now carried out with the IntraBeam on suitable patients with small breast carcinomas. This procedure is performed with a radiation unit that can be used in the operating theatre during surgery. After removal of the tumour, the tumour bed can be carefully radiated with a spherical applicator which contains a source of x-rays. This way, the relevant high-risk region within the breast (also the region with the highest risk for a localised recurrence of the breast cancer) is targeted with radiation, without affecting the surrounding tissue and particularly the skin.

Hirslanden Radiotherapy collaborates closely with the University Hospital Zurich in this area.


The major advantage of the IORT is that the boost can be applied at the earliest possible time, exactly and directly where the tumour was removed. The therapy phase is shortened to just one to one and a half weeks.

Applicator in the wound cavity

Diagram of an applicator in the wound cavity. The low energy level means that only very strictly defined localised radiation of the breast gland tissue occurs.