Principles of radiotherapy for invasive breast cancerOptimization of individual treatment:What is important is the individualization of radi
Principles of radiotherapy for invasive breast cancer
Optimization of individual treatment:
What is important is the individualization of radiotherapy planning and implementation. CT based treatment plans are encouraged to delineate the target area and the volume of the organ. The uniformity of the dose and the protection of the normal tissue can be realized by the use of the compensator, such as the wedge, the forward planning and the intensity modulated radiotherapy (IMRT).
Try breathing control techniques, including deep inspiration breath hold and prone position, to further reduce the adjacent normal tissues especially in heart and lung dose. In the case of breast conserving therapy, dose irradiation can be achieved by the use of superficial electrons, photons, or close range radiotherapy. When there is an indication of the amount of scar on the chest wall, it is usually treated with electron or photon.
1 times a week to verify the consistency of the daily settings. In some cases, more frequent imaging may be justified. 1 times a week. Imaging is not recommended 1 times a day.
Whole breast irradiation:
The target area was defined as the whole breast tissue. Whole milk should accept 46 - 50Gy/23 - 25FR or - 42.5Gy/15 - 16fr (preferred low split). All doses were given 5 days a week. In patients with a higher risk of recurrence, it is recommended to push the tumor bed. The typical additional dose is 10-16Gy/4-8fr.
Chest wall radiotherapy (including breast reconstruction):
The target area included the ipsilateral chest wall, the scar after mastectomy, and the drainage site. Depending on whether the patient has had breast reconstruction, some techniques using photons and / or electrons are justified. CT based treatment plans are encouraged to determine lung and cardiac volumes and minimize exposure to these organs. Dose of chest wall 46-50Gy/23-25fr + scar push 2Gy/fr to the total dose of about 60Gy. All doses were given 5 days a week. Special consideration should be given to the use of padding materials to ensure that the skin dose is appropriate.
Regional lymph node irradiation:
Target delineation is best accomplished by using a CT based treatment plan. For both the supraclavicular and axillary lymph nodes, the depth of the prescription varies depending on the patient's anatomy. For the identification of the internal mammary lymph nodes, the internal mammary artery and vein may be used instead of the lymph node location (as these nodes are usually not visible in the planned image). According to the randomized study and recent study of radiotherapy after mastectomy, radiation therapy should be considered in the treatment of regional lymph node irradiation. When dealing with the volume of the internal mammary lymph nodes, the CT treatment plan should be used to assess the normal tissue, especially the heart and lung dose, and the dose limit. The dose of regional lymph nodes was 46-50Gy/23-25fr. All doses were given for 5 days.
Accelerated partial breast irradiation (APBI):
A preliminary study of accelerated partial breast irradiation tips in selective patients with early breast cancer local control rate and can receive the standard whole breast radiotherapy for comparison. However, compared with standard whole breast irradiation, recent studies have shown that accelerated partial breast irradiation results in poor cosmetic outcomes. Follow up studies are limited and ongoing. Encourage patients to participate in clinical trials. If you do not meet the test conditions, according to the American Society for radiation oncology (ASTRO) consensus statement may be suitable for accelerated partial breast irradiation in patients over 60 years old, is a non BRCA 1/2 mutation carriers, single lesion T1N0 ER positive tumor initial surgical treatment of women. Histology should be an invasive catheter or a good catheter subtype and there is no extensive ductal carcinoma in situ or lobular carcinoma in situ.
Tumor bed prescription 34Gy/10fr bid irradiation or 38.5Gy/10fr bid photon beam therapy. Other segmentation schemes are currently under study.
NCCN guide first edition 2016