Proton therapy for the liver cancer treatment
What is proton therapy?
Proton therapy - is advanced and high-precision radiation therapy for tumours. It is a form of radiation therapy used to destroy cancer cells. Instead of X-rays used in radiation therapy, proton therapy uses the high energy of protons, which have a more accurate effect on the tumour. Compared to other radiological methods, proton therapy focuses more power on the tumour itself with less radiation on the surrounding healthy tissues.
During treatment with proton therapy, the task is to focus the beam of protons on the shape and size of the tumour. The beam kills tumour cells layer by layer while sparing the surrounding healthy tissues.
A detailed description of proton radiation
Proton therapy for liver cancer is carried out outpatient in a particular room. Before the procedure, visualization tests such as CT or MRI are carried out, which help obtain images of the tumour and surrounding tissues. Sometimes the doctor marks the body, indicating the treatment area. The proton therapy session lasts 15 to 30 minutes, and it depends on the location, size and number of the tumour.
The position of the patient's body is essential in proton therapy for liver tumours. Therefore, the treating team may take some time to adjust the optimal position and tools to achieve the exact position of a proton beam.
A large machine accelerates protons and creates energy. A beam of protons focuses this energy in the body precisely at the depth where the tumour is located. The proton portal can move around the patient to treat the tumour from several positions. Proton therapy for liver cancer treatment is a painless method. Therefore the patient does not feel the beam of proton that enters the body and affects the tumour.
Advantages of the treatment
Proton therapy is rightfully considered the newest and most advanced method of radiotherapy. Due to its advantages, this type of liver cancer treatment is suitable in a situation where treatment options are limited for several reasons. Here are the benefits of proton radiation therapy over other treatments:
- greater radiation power and, consequently, the effectiveness of the method (compared to other radiotherapy methods);
- tumour control due to more accurate radiation targeting;
- the minimum dose of radiation to neighbouring healthy tissues;
- minimal side effects rate;
- short course and painless method;
- treatment takes place on an outpatient basis;
- proton radiation therapy does not require a recovery period;
- the ability to combine with other systemic and surgical methods.
Results and statistics
The incidence of liver and intrahepatic bile duct tumours is growing faster than other cancers. Unfortunately, a small proportion of patients are suitable for surgical treatment due to medical or anatomical reasons, which leads to a low 5-year overall survival rate - of 18%. The role of proton radiation therapy has expanded significantly in this population of patients.
Based on a study of patients undergoing radiation therapy with a proton beam for a liver tumour conducted by the Proton Collaborative Group, indicators of overall survival and survival without progression were derived. The overall survival rate was 71.5%; survival without liver cancer progression was 67.3%.
In addition, patients treated with proton therapy and conventional radiation therapy have been monitored for ten years. The average total survival rate for proton therapy was 31 months compared to 14 months for traditional radiation therapy. Two years later, the total survival rate for proton patients was 59%, while it was only 28.6% with conventional radiotherapy.
- National Library of Medicine: Effectiveness of Proton Beam Therapy on Liver Metastases of Esophageal Cancer
- National Library of Medicine: Proton beam therapy for metastatic liver tumors
- Journal of Gastrointestinal Oncology: Proton beam therapy for liver cancers
- Provision Healthcare: Liver cancer patients may benefit from advantages of proton therapy
- Gastrointestinal Cancers: Consensus Report From the Miami Liver Proton Therapy Conference
- International journal of Radiation oncology: Protons for Unresectable Hepatocellular Carcinoma: Liver Decompensation and Overall Survival