This section provides a detailed explanation of the differences between proton therapy and heavy ion therapy.
Different Atomic Nuclei Used in Proton and Heavy Ion Therapy
Proton therapy and heavy ion therapy are gaining attention as new cancer treatment methods. Both techniques irradiate cancer cells with high-energy particles to destroy them. Unlike X-rays, these particle beams concentrate their energy in the cancer cells with minimal spread, thereby reducing the impact on surrounding areas.
The main difference between these two therapies lies in the atomic nuclei used. Proton therapy uses hydrogen nuclei, while heavy ion therapy uses carbon nuclei, which are twelve times more massive. This allows heavy ion therapy to attack cancer cells with much greater energy.
Heavy Ion Therapy Has Higher Energy for Cells/Proton Therapy Has a Wider Treatment Range
Compared to proton therapy, heavy ion therapy delivers three to four times the energy to cells. This makes it particularly effective for cancer types like soft tissue sarcomas and osteosarcomas, which are often resistant to conventional radiation treatments.
However, this high destructive power also poses a risk of affecting healthy cells, meaning that heavy ion therapy may not be suitable for all cases and should be carefully considered based on the treatment area and the patient’s condition.
Proton therapy, while delivering 1.2 times the energy of conventional X-ray radiation, can selectively target cancer cells, minimizing effects on healthy cells. This high selectivity enables it to treat a broader range of cancer cells, potentially offering more applications than heavy ion therapy. Moreover, the combination of moderate energy strength and selectivity results in fewer side effects compared to other radiation therapies.
Advantages and Disadvantages of Proton and Heavy Ion Therapy
Advantages and Disadvantages of Proton Therapy
Proton therapy is gaining attention as a new cancer treatment option. Its advantages include a lower physical burden and fewer side effects compared to surgical, drug, and conventional radiation treatments. It is especially effective for tumors near organs sensitive to radiation, tumors difficult to treat with X-ray therapy, and large tumors. The treatment is painless, leaves no scars, and is suitable for outpatient care, making it easier to return to daily life.
On the other hand, proton therapy has some drawbacks. It may not be suitable for stage IV cancers with metastasis or cancers with lymph node involvement. It is also not used for gastric or colon cancers. Additionally, the treatment is classified as “advanced medical care” and is not covered by insurance, meaning patients bear the full cost. “Advanced medical care” refers to a system in which new medical technologies are provided alongside insured medical treatments, available only at facilities meeting certain standards.
Advantages and Disadvantages of Heavy Ion Therapy
Heavy ion therapy is known for its cutting-edge technology in cancer treatment. Compared to conventional radiation and X-ray treatments, it has a significantly stronger cell-killing effect and requires fewer treatment sessions. It also allows for shorter treatment periods (1 day to 3 weeks) and is available for outpatient care, a considerable benefit for elderly or physically weakened patients.
Carbon ions used in heavy ion therapy have a larger mass than the hydrogen ions used in proton therapy, providing a stronger impact on cancer cells. Specifically, it has 2–3 times the cell-killing effect of proton therapy, making it effective even for deep-seated cancers, hypoxic tumors, and certain cancers such as osteosarcoma.
The treatment is typically performed once a day, three to five times per week, for a total of 1 to 40 sessions, with each session lasting 15–30 minutes on average. This is a relatively short treatment period compared to other radiation therapies.
However, heavy ion therapy has some disadvantages. The cost is one major issue. Health insurance coverage is limited, and the treatment often falls under “advanced medical care,” with an estimated treatment cost of around 3 million yen. Additionally, the facilities and equipment required for heavy ion therapy are more costly than those for proton therapy, limiting the number of available facilities and specialists.
Choosing the Appropriate Treatment Based on Conditions and Side Effects
Proton therapy is effective for large or deep-seated cancers, while heavy ion therapy is anticipated to work well on radio-resistant cancers. However, both therapies may not be applicable for cancers in the digestive tract due to risks such as intestinal damage or perforation. Although their impact on healthy cells is generally lower than conventional radiation, side effects still exist. Choosing the optimal therapy requires careful consideration of the patient’s condition, tumor location, type, and the risk of side effects.Additionally, immunotherapy, particularly a six-type composite immunotherapy, is worth considering as a cancer treatment option. Immunotherapy, which activates the body’s immune system to attack cancer cells, can be used in combination with radiation therapy for potentially more effective treatment results.