Proton and heavy-ion radiotherapy are mentioned repeatedly because of their physical property: energy is released in a concentrated way only once it reaches the intended depth. This property determines their ability to protect nearby vital organs, and also means that not every patient is a suitable candidate. This article explains the practical process for Malaysian patients travelling to Shanghai, from assessment thresholds to scheduling rhythm.
1. What the Bragg peak actually means
Conventional photon radiotherapy is like a highly penetrating beam that releases energy continuously along its path through the body, so normal tissue beyond the target volume also receives dose. Protons and heavy ions are different: the energy is released mainly in a concentrated way once the intended depth is reached, forming what is called the “Bragg peak”.
For patients whose lesions lie immediately next to the optic nerve, brainstem, spinal cord or heart, this difference often determines whether treatment is feasible at all.
2. Which situations are most often assessed
- Complex lesions of the skull base and within the skull, such as chordoma and some meningiomas
- Tumours in children and adolescents (a group more sensitive to the long-term risk of second tumours)
- Locally advanced prostate, liver or lung cancer and similar situations where nearby organs need protection
- Recurrent lesions that need re-irradiation after previous radiotherapy
Suitability depends on lesion location, size, pathological type and previous treatment history, and must be judged case by case by the radiotherapy team. Publicly available information shows that Shanghai Proton and Heavy Ion Hospital has treated more than 7,000 cases in total and has developed a relatively mature assessment pathway.
3. Assessment process and thresholds
- Document submission: pathology slides and immunohistochemistry reports, recent contrast-enhanced imaging (including raw DICOM data), previous radiotherapy records and dosimetry data.
- First-round assessment: the radiotherapy department judges whether there is an indication for particle therapy.
- Additional tests: localisation CT/MRI and performance status assessment completed in hospital where necessary.
- Plan and scheduling: determining the beam type, fractionation schedule and treatment duration.
How complete the documents are directly affects how many rounds of assessment are needed. In practice, cases with complete imaging and dosimetry data are assessed noticeably faster.
4. Treatment duration and travel arrangements
Proton therapy usually requires several consecutive weeks with multiple sessions per week, and is mainly delivered on an outpatient basis. This means families need to arrange accommodation and caregiving for a long stay rather than a short visit.
| Step | Approximate timing | Family preparation |
|---|---|---|
| Assessment and localisation | Within a few days of arriving at the hospital | Bring original pathology and imaging materials |
| Treatment planning | A few days after localisation | Confirm the number of fractions with the doctor |
| Consecutive irradiation | Several weeks, multiple sessions per week | Stay close to the hospital to reduce commuting |
| Review | After treatment ends | Coordinate with the follow-up plan back home |
5. Frequently asked questions
Q: Can I have proton therapy after conventional radiotherapy? It can be assessed, but previous dosimetry data is needed to judge how much more dose the normal tissue can tolerate.
Q: Is hospitalisation required during treatment? Most treatment is outpatient; a minority of cases require admission, arranged by the hospital according to the condition.
Q: Does a family member need to accompany the patient throughout? At least one family member is recommended, especially for patients who need language assistance and daily care.
Whether a patient is accepted and which beam type and fractionation schedule is used are determined independently by the hospital’s radiotherapy team. This article does not constitute medical advice.