Breast cancer

Postoperative external beam radiotherapy is usually performed over 15, fractions, thus over a period of 3 weeks with 5 weekly fractions. For more favourable tumours, a partial breast irradiation might be the best method. For tumours with specific risk factors, the dose to the initial tumour site is increased in comparison to the doce to the whole breast (designated as “boost”).

The exact detection of the patient surface and adaptation to the breathing phases is essential for an optimal treatment, including the best possible dose coverage of the prescibed dose in the target (breast or chest wall, possibly lymph node areas) and the best posible protection of healthy tissue outside the target volume. Radiotherapy of the left breast requires a treatment only in deep inspiration. In deep inspiration, the lung volume expands and increases the distance of the breast tissue to the heart. Thus, radiotherapy in deep inspiration is associated with the best possible heart protection.

Patients in WEGE are treated with the most sophisticated system for surface detection and deep inspiration breath hold technique (ExacTrac Dynamic, Brainlab). The system combines the detection of the surface with the termal surface information. Baseline imaging information for planning are acquired during an appointment for treatment planning. Computed tomography images are acquired in normal breathing and in deep inspiration breath hold. With the ExacTrac Dynamic system, no addition skin markings are needed for patient positioning.

The 4D Thermal Camera creates a highly accurate and reliable hybrid thermal surface by correlating the patient’s heat signature to their reconstructed 3D surface structure. To achieve this, 300.000 3D surface points are acquired and matched to the heat signal generated by the thermal camera, creating another dimension to track their position. The patient receives a continuous visual feedback of the required surface position. Radiation is only triggered in the correct phase of deep inspiration. Thus, depending on the duration of the breath hold, each patient determines the duration of the radiation phases.

The majority of patients with the diagnosis of breast cancer receive radiotherapy of the breast after breast conserving operation. The local cancer excision in combination with radiotherapy has shown to be associated with the same tumour control and survival as the removal of the complete breast (mastectomy). Only in patients with more advanced, larger tumours or tumours with an invasion of the skin or chest wall, the removal of the complete breast is still recommended. In these patients, breast reconstruction methods are discussed and postoperative radiotherapy of the remaining chest wall is decided after discusion of individual risk factors in a multidisciplinary tumour conference in the respective breast cancer centre.

Apart from the radiotherapy of the breast or chest wall, the decision of treatment of locoregional lymph nodes made. Locoregional lymph nodes include axillary, infra- and supraclavicular lymph nodes (lateral lymph nodes in the direction of the axilla and neck) and internal mammary lymph nodes (medial lymph nodes near the sternum). Patients with positive lymph nodes usually need a postoperative radiotherapy of locoregional lymph nodes. Radiotherapy of the lymph nodes might be recommended instead of an operation, as side effects of radiotherapy have been shown to be considerably lower in comparison to an operation (lymph oedema) in recent studies without compromising tumour control.

Patients present at our clinic for their first appointment with their reports, prior images and multidisciplinary tumour conference recommendation. The treatment is discussed and explained in the context of the individual patient situation, including the timing, duration, potential problems that might occur and individual questions.

Brachytherapy is based on the placement of a radioactive source in the target tissue. In contrast to external beam radiotherapy, the dose is not applied from the outside through the skin and potentially other organs, but directly placed in the target tissue. The consequence is the best possible treatment conformality (best focus on a specific area) and the lowest doses to organs as lung or heart. Fraction doses in brachytherapy are usually considerably higher and treatment duration considerably shorter in comparison to external beam radiotherapy.

Adjuvant breast cancer brachytherapy is a well established treatment that has been evaluated in several randomized studies with many thousands of patients, thus endorsed by all national and international guidelines for breats cancer treatment. An important advantage is an improved cosmesis, including reduced long-term impact on the skin and breast tissue. A disadvantage is the invasive character of the treatment. Brachytherapy is always a partial breats irradiation, recommended only for patients with smaller, less aggressive tumours without lymph node involvement.

Adjuvant breast cancer brachytherapy commonly applied in 8 twice daily fractions during an inpatient stay at WEGE Klinik over a period of 5 days (usualy Monday to Friday). At the first day, applicator catheters are implanted in the breast under general anaesthesia. With the implanted catheters in situ, a planning computed tomography is performed as the basis for three-dimensional treament planning. The first brachytherapy fraction is commonly applied on the afternoon of the first day. During treatment, the radioactive source (Iridium-192) is placed in the breast tissue via the applicator catheters. The source remains for a specific time at specific places. These times and places are calculated in the treatment plan to deliver the required dose distribution. The duration of each fraction is about 15 minutes.