Palliative Radiation Treatment of Breast CancerMedical editor Bjørn Naume MD
Oslo University Hospital
Palliative radiation therapy for breast cancer is administered to reduce symptoms from metastases.
Radiation therapy is offered liberally for local symptoms.
There must be a definite connection between the actual metastasis(es) and the symptom(s).
- Metastases which cause for example pain, pressure symptoms, airway obstruction, bleeding, and secretion.
- To relieve painful or uncomfortable symptoms.
|Target volume definitions in accordance with ICRU |
(International Commission on Radiation Units and Measurements)
|GTV (=Gross Tumor Volume)
Palpable or visible/identifiable spread of malignant growth.
|CTV (=Clinical Target Volume)
Tissue volume containing GTV and subclinical microscopic malignant disease.
|ITV (=Internal Target Volume)
Volume containing CTV and an internal margin taking into account internal movements and changes in CTV. This is the volume that should receive an optimal dose.
|PTV (=Planning Target Volume)
||Geometric volume containing ITV and one set-up margin taking into account patient movement, patient positioning, and field modeling.|
- To prepare a treatment plan, it is necessary to have overview of tumor localization in both the actual treatment area and in other regions.
- It is usually necessary to perform imaging of the treatment area: X-ray, bone scintigraphy, MRI for skeletal metastases, CT of the chest for lung metastases, ultrasound, or CT for lymph node or soft tissue/subcutaneous metastases. MRI of the head is preferable for brain metastases.
- "Simplified" CT-based dose planning is often performed.
- It is important that the patients are well medicated for pain and can lie on their back during simulation.
- Most often, 10 fractions of 3 Gy are used for palliative purposes.
- Painful skeletal metastases may be alternatively treated with 8 Gy x 1. In studies, it has been shown to be as effective for pain reduction as 3 Gy x 10, but is thought to give less re- mineralisation of bone than 3 Gy x 10. The treatment with 8 Gy x 1 is most often given to patients with assumed short life expectancy when rapid symptom reduction and short treatment time is the most important. This treatment may be repeated for recurrent pains.
- Risk for fracture of the spine and long bones are usually given 3 Gy x 10. For localized spread 2 Gy x 25 may be relevant. Operative fixation should be considered prior to radiation therapy for patients with good general status.
- For multiple brain metastases, 3 Gy x 10 towards the entire brain is administered.
- For 1-2 brain metastases up to 2 cm, resection may be considered followed by radiation therapy 3 Gy x 10 towards the entire brain (or stereotactic treatment). Postoperative radiation treatment starts when the operation area is totally healed, usually after 2-4 weeks. One may also consider referring the patient for treatment with stereotactic radiation.
Follow-upMost of the side effects, which may occur during the treatment develop from other tissues/organs in the radiation area. The dosage used for pure symptom palliation is kept low to reduce the risk of acute side effects as much as possible.
The total radiation dose is most often at a level (3 Gy x 10), which reduces the risk of delayed side effects.
These patients are at late stage of their cancer. Frequent follow-up is important to achieve satisfactory reduction of symptoms.
Follow-up usually occurs locally at the referring hospital or general practitioner.