At a glance
Proton therapy is a type of radiation treatment that uses a beam of protons, positively charged particles, to destroy cancer cells with great precision. Unlike conventional X-ray radiation, which deposits energy along its entire path through the body, a proton beam can be tuned to release most of its energy at a specific depth inside the tumour and then stop.
This stopping behaviour, called the Bragg peak, means the healthy tissue in front of and behind the tumour receives far less radiation. The result is that doctors can deliver a high dose to the cancer while reducing the amount of radiation reaching nearby organs, nerves, or developing tissue.
Medical Condition
Proton therapy is chosen when a tumour sits close to critical structures, when the patient is a child whose growing body is especially vulnerable to radiation damage, or when conventional radiation has already been used and another course of treatment is needed. It is not a replacement for all radiation, but it fits certain situations particularly well.
- Brain and skull-base tumours, including chordoma (a tumour of the spine or skull base) and craniopharyngioma (a tumour near the pituitary gland)
- Head and neck cancers where the tumour is near the eyes, spinal cord, or salivary glands
- Paediatric cancers, especially medulloblastoma (a childhood brain tumour) and other solid tumours in children
- Prostate cancer, particularly in men who want to reduce the risk of bowel or bladder side effects
- Lung, liver, and pancreatic tumours that are surgically difficult to reach
- Spinal and paraspinal tumours that lie next to the spinal cord
- Re-irradiation, meaning a second course of radiation therapy for cancer that has returned in an area already treated before
- Ocular melanoma (a rare cancer of the eye)
Proton therapy is not suitable for every cancer patient. Tumours that have spread widely through the body, cancers that respond better to chemotherapy alone, and situations where the patient cannot lie still for treatment sessions are among the reasons a tumour board might recommend a different approach.
- Widespread metastatic disease (cancer that has spread to many parts of the body) where systemic treatment is the priority
- Tumours that move significantly with breathing and cannot be managed with breath-hold techniques
- Patients with certain implanted metal devices near the treatment area, depending on the device
- Cancers that are better controlled by surgery or systemic therapy alone
Risks & Complications
Proton therapy is generally well tolerated, but like any radiation treatment it can cause side effects, most of which depend on which part of the body is being treated.
- Fatigue (tiredness that builds up over the course of treatment and can last weeks after it ends)
- Skin redness, irritation, or soreness at the entry point of the beam
- Hair loss in the area being treated, which may be temporary or permanent depending on the dose
- Nausea or loss of appetite, especially when the abdomen or brain is treated
- Swelling in or around the treated area
- Difficulty swallowing, dry mouth, or changes in taste when the head and neck are treated
- Urinary or bowel changes when the pelvis is treated, such as increased urgency or mild discomfort
- Late effects, meaning side effects that appear months or years after treatment, including changes to nearby organs or secondary radiation-induced cancer (rare)
- Uncertainty in beam placement due to organ movement, which the treatment team actively monitors and manages
Preparation & Procedure
Before the first treatment session, the patient goes through a planning phase that can take one to two weeks. This phase exists because proton therapy requires extreme accuracy, and the team needs detailed maps of the tumour and surrounding anatomy before any radiation is delivered.
On the day of each treatment session, fasting is usually not required unless anaesthesia is needed, which is common for young children who cannot lie still. Patients are asked to arrive with a consistent body state: the same bladder filling, the same bowel preparation if the pelvis is being treated, and ideally the same weight throughout the course of treatment, because changes in body shape can shift where the beam lands.
Certain medications, especially blood thinners and some supplements, may be paused based on the specific treatment site. Smoking and alcohol are strongly discouraged throughout treatment because they affect tissue healing and can change the way the body responds to radiation. The clinical team gives each patient written instructions tailored to their situation.
Tests and scans that are typically run during the planning phase include:
- CT scan of the treatment area, used to map the exact shape and density of tissue the beam will pass through
- MRI scan, often fused with the CT images to give a clearer picture of the tumour edges
- PET scan (positron emission tomography, a scan that shows how active cells are), ordered when the oncologist needs to confirm tumour boundaries
- Blood tests to check general health and organ function
- Dental review if the head or neck is being treated, because radiation can affect jaw bones and teeth
The treatment itself follows a set sequence each day:
- 1. The patient is positioned on the treatment table in exactly the same way as during the planning scan, using a custom-made immobilisation device such as a plastic mask for head treatments or a body mould for lower body treatments.
- 2. X-rays or CT images are taken while the patient lies on the table to confirm the tumour is in the planned position before any radiation begins.
- 3. The radiation therapist leaves the room and the proton beam is delivered from one or more angles. The session itself usually lasts only a few minutes.
- 4. The patient is helped off the table and can leave the department. Proton therapy does not make the patient radioactive, so no isolation is needed after sessions.
Aftercare
Each session of proton therapy is outpatient, meaning most patients go home the same day. A full course of treatment typically spans several weeks with sessions on most weekdays, so aftercare is not a single event but an ongoing routine that runs alongside treatment and continues after it ends.
- Fatigue is the most common experience during and after treatment. Most patients are encouraged to rest when tired but to keep gentle activity such as short walks as tolerated.
- Skin in the treated area may become red or sensitive. The care team usually advises on specific skin products to use and what to avoid, such as tight clothing, direct sun, and very hot water.
- If the head or neck is treated, mouth care becomes a daily routine: rinsing, keeping the mouth moist, and attending dental check-ups as recommended.
- Eating habits may need to adjust if the abdomen or throat is in the treatment field. A dietitian is often part of the care team during this period.
- Patients are generally advised not to drive immediately after sessions if they feel fatigued, and to arrange transport accordingly.
- Follow-up imaging scans, usually CT or MRI, are scheduled at set intervals after treatment ends, often at one to three months and then every few months for the first years, to assess the tumour response.
- Blood tests are repeated at follow-up visits to check for any effects on surrounding organs.
- If the patient travelled abroad for treatment, the local oncologist at home receives a full treatment summary so follow-up care can continue seamlessly.
- Long-term monitoring continues for years after treatment because late radiation effects, though uncommon, can appear over time.
Cost & What Determines It
Proton therapy is among the more expensive forms of cancer treatment worldwide, largely because the machines that produce proton beams, called cyclotrons or synchrotrons, require enormous facilities and very high maintenance costs. Two patients with the same diagnosis can face very different bills depending on how complex their tumour geometry is, how many sessions are prescribed, and which country they travel to.
- Tumour complexity and stage: a tumour that requires multiple beam angles, a very large treatment volume, or combined chemotherapy adds significant planning time and cost
- Number of treatment sessions: some protocols span fewer than ten sessions while others run for six to eight weeks of daily treatment
- Hospital class and country: proton centres in the United States, Japan, and Western Europe generally charge more than those in South Korea, China, or India, though pricing structures differ widely even within one country
- Planning scans and simulation: the CT, MRI, and PET scans done specifically for treatment planning are often billed separately from the treatment sessions themselves
- Custom immobilisation devices: the masks, moulds, or body casts made for each patient are usually charged individually
- Anaesthesia: patients who require sedation for each session, such as young children, incur additional anaesthesia fees for every visit
- Concurrent chemotherapy: if chemotherapy is given alongside radiation, its drugs, infusion appointments, and monitoring tests add to the overall cost
- Follow-up imaging: post-treatment scans to assess response are usually not included in the initial treatment package
- Accommodation and living costs: a typical course of treatment requires the patient to stay near the centre for several weeks, so housing, food, and local transport are real budget items
A hospital package for proton therapy often bundles the planning session, the treatment sessions themselves, and the custom immobilisation device into one quoted price. Items that are typically billed separately include planning scans, blood tests, oncologist consultation fees, anaesthesia if needed, any chemotherapy drugs, and follow-up appointments after treatment ends. Asking the hospital for a detailed written breakdown before committing is the only way to know exactly what is and is not covered.
BPJS Kesehatan does not cover treatment received outside Indonesia, and most Indonesian private health insurance policies also exclude overseas care. Patients who choose proton therapy abroad almost always pay out of pocket or rely on private international health insurance that explicitly covers oncology treatment abroad. Before travelling, requesting a formal written cost estimate from the hospital, itemised by service, helps prevent unexpected charges and makes it easier to plan a realistic total budget including travel and accommodation.
Frequently Asked Questions
How many sessions of proton therapy will I need?
The number of sessions depends on the type and location of your cancer, and your doctor will decide after reviewing your case. Most courses run anywhere from a few sessions to several weeks of daily treatments, five days a week. Your oncologist will give you a personal treatment plan before you start.
What does proton therapy feel like during treatment?
The treatment itself is painless, similar to lying still for an X-ray. You will hear the machine moving around you, but there is no sensation when the proton beam is delivered. Some people develop tiredness or skin sensitivity in the treated area after several sessions, but this varies from person to person.
How soon will proton therapy start working?
The beam damages cancer cells from the very first session, but visible results, such as a shrinking tumour, usually take weeks to months to appear on scans. Your medical team will schedule follow-up imaging at set intervals to track how your body is responding. Responses differ depending on the cancer type and its location.
How much does proton therapy cost?
The cost varies quite a bit depending on how many sessions are prescribed, the complexity of the treatment plan, the type of cancer being treated, and the class of hospital providing care. Because these factors combine differently for every patient, a written estimate from the treating hospital is the only reliable way to know your actual figure.
This page is general information, not a substitute for medical advice. Every case is different. Your doctor decides what is right for you.
