Proton therapy is a type of radiation therapy that is also known as proton beam therapy.
In this therapy, high-energy protons (positively charged particles) are used instead of X-rays to destroy cancer cells.
Proton therapy is a painless therapy in which an external beam is passed from a machine and penetrates inside the skin.
The functionality of Proton therapy
Cyclotron or synchrotron is the machine that speeds up proton particles.
The high speed generates energy in the proton particles.
The high-energy protons penetrate to the anticipated location inside the body.
The protons then contribute to the targeted radiation dose in the tumor.
In proton therapy, less amount of radiation dose reaches the exterior area of the tumor.
But in X-ray radiation therapy, the dose of radiation that reaches the exterior area of the tumor is high.
Therefore, the risk of damages to the adjacent area of the tumor is high in X-ray radiation treatment and can lead to an increased side effect burden.
Proton therapy and cancer treatment
Proton therapy can treat benign tumors as well as malignant tumors that spread to adjacent areas.
Proton therapy is effective for brain and spinal cord cancer because the other associated healthy tissues will not impact because of this targeted therapy.
Proton therapy is also effective for pediatric patients with brain and spinal cord cancer.
Eye cancer like retinoblastoma and orbital rhabdomyosarcoma can also be treated with proton therapy.
The doctor may prescribe proton therapy for the following cancer treatment:
- Cancer in the central nervous system such as chondrosarcoma, chordoma, malignant meningioma
- Head and neck cancers including paranasal sinus cancer, cancer in the nasal cavity, and nasopharyngeal cancers
- Eye cancer like choroidal melanoma, uveal melanoma
- Liver cancer
- Lung cancer
- Pelvic and spinal sarcomas develop due to cancer occurring in soft-tissue and bone
- Prostate cancer
- Nonmalignant brain tumors
Proton therapy is given to the patients on an outpatient basis.
Therefore, the patient does not need hospitalization.
However, the requirement of several sessions depends upon the stages and type of cancer.
In proton therapy, the regular radiation doses are usually larger.
The numbers of radiation cycles are less in this therapy.
Therefore, this radiation therapy is also called as stereotactic body radiation.
Radiosurgery is given by a single, large dose of radiation.
Time duration for each cycle
A proton radiation therapy duration usually lasts for 15 to 30 minutes.
It covers from entering the treatment room to leaving the room.
The time also varies depending upon the location of the cancer and the number of treatment cycle requirements.
Time duration also varies depending upon the visibility of the tumor with X-ray or CT scans during the positioning process.
Risks and benefits
Following are the benefits of proton therapy compared with X-ray:
Almost 60% less amount of radiation is reachable to the healthy tissues around the tumor.
Therefore, the risk of damage to healthy tissues becomes lower with proton therapy.
A higher dose of radiation is given to the tumor in proton therapy.
Therefore, the chances of targeting tumor cells are higher with proton therapy.
Proton therapy has less serious side effects like low blood counts, nausea, and fatigue during and post-treatment.
Following are the drawbacks associated with proton therapy:
Proton therapy requires specialized costly equipment that is not available in every oncology hospital.
Very few world-class oncology healthcare organizations have a proton therapy facility.
The cost of proton therapy is higher than X-ray radiation treatment.
Therefore, a patient needs to check the detail of health insurance coverage before opting the proton therapy.
Every type of cancer cannot be treated with proton therapy.
Proton therapy is painless, but associated side effects include skin problems like irritation, redness, dryness, inflammation, peeling, or blister formation.
The side effects of proton therapy may increase in case of combination with chemotherapy.
However, the size and location of tumors also impact the side effects associated with proton therapy.