Intraoperative radiotherapy (IORT for breast cancer)

In collaboration with the Department of Gynaecology (Prof. Janni), intraoperative radiotherapy has been used at the UK Ulm since 2010 for patients with breast cancer (breast carcinoma).
In intraoperative radiotherapy, a high single-dose is applied to the former tumour region (tumour bed) during the operation, directly after the tumour has been removed. For this purpose, a ball applicator (Fig. 1) is inserted into the resection cavity while the patient is under anaesthesia. This enables the delivery of a 50kV X-ray beam, with which a high dose can be applied both directly to the resection area and a few millimetres deep. The radiation dose drops very steeply directly behind the applicator, so that only 25% of the dose reaches a distance of 1 cm. This means that the surrounding tissue can be optimally protected. The anaesthesia can be extended by 20 - 45 minutes depending on the preparation and irradiation time. After IORT, the tube is removed and the operation is completed as planned.
Intraoperative irradiation can be performed as sole irradiation or as a so-called early boost (dose saturation) of the tumour bed prior to external irradiation via the skin (percutaneous irradiation).
Intraoperative radiotherapy alone is a therapeutic alternative for older patients (>60 years) with small tumours (T1) and favourable tumour biology (G1-2, hormone receptor positive, Her 2 new negative). The intraoperative one-time dose is then 20 Gy. This means that several weeks of radiotherapy after the operation can be avoided.
Following earlier radiotherapy to the breast, a recurrence can occur, usually many years later. In favourable cases, the tumour can be surgically removed in the gynaecology clinic. In these cases, intraoperative radiotherapy of the tumour bed is performed as a boost and the tumour bed is marked with titanium clips. This is followed by small-volume, dose-reduced radiotherapy of the tumour bed. This allows a curative second radiotherapy treatment to be carried out despite the earlier pre-irradiation.
Patients who are not eligible for one-time IORT due to their age (≤ 60 years) or their tumour biology can benefit from IORT as a boost in individual cases. In this treatment, 9 Gy is applied intraoperatively and the tumour bed is marked with titanium clips. This is followed by percutaneous radiotherapy of the entire breast approximately four weeks after the operation. This percutaneous radiotherapy can be shortened by one week using IORT.
To date, over 500 patients have been irradiated with IORT in Ulm