Carbon ion therapy for head and neck cancer has been used in Japan for more than 30 years for tumors of the nose, sinuses, salivary glands and eye area, where surgery can cost facial appearance, vision or speech. Since April 2018 Japan has covered carbon ion radiotherapy for malignant head and neck tumors under public insurance, and QST Hospital alone has treated 1,490 head and neck patients. This guide covers which head and neck cancers are eligible, the 4-week schedule, carbon ion cancer treatment cost for overseas patients and the documents to prepare. To find out whether your records qualify and what it may cost, request a head and neck carbon ion therapy consultation.
Which head and neck cancers are eligible for carbon ion therapy?
Head and neck cancer is an umbrella term for cancers of the mouth, throat, nose, salivary glands and eye area. Carbon ion therapy is especially valuable for non-squamous cell carcinomas such as adenoid cystic carcinoma, mucosal malignant melanoma, adenocarcinoma and sarcoma, which often respond poorly to conventional X-ray radiation. Carbon ions release most of their energy at the tumor depth (the Bragg peak) and have strong cell-killing power, so a high dose can be concentrated on the tumor even next to the optic nerve or brainstem. See What is carbon ion therapy? for the basics.
The table summarizes the head and neck criteria published in QST Hospital's English guide for overseas patients.
| Group | Eligible cases | Usually not eligible |
|---|---|---|
| Non-squamous carcinoma | Adenoid cystic carcinoma, adenocarcinoma, etc. of the head and neck and orbit | Widespread spread to other organs |
| Malignant melanoma | Mucosal melanoma of the nose, sinuses, mouth, etc. | Distant metastasis |
| Squamous cell carcinoma | Sites other than the oral cavity, pharynx and larynx, close to critical organs so that conventional radiation cannot deliver enough dose | Oral cavity, pharynx and larynx (respond well to conventional radiation) |
| Sarcoma | Bone and soft tissue sarcoma of the head and neck | Extensive metal in the field is judged case by case |
The common condition is that surgery is difficult or not desired. Distant metastasis usually rules out treatment, but QST notes that some patients, such as those with slowly growing lung metastases from adenoid cystic carcinoma, live long and may be considered. See also Head and neck cancer carbon ion therapy — indications and 16-session schedule.
What are the results for adenoid cystic carcinoma and mucosal melanoma?
The key data come from the Japanese multicenter group J-CROS (four carbon ion cancer treatment centers) and from a German Heidelberg-led study — all real patient outcomes.
| Study | Patients | Main results |
|---|---|---|
| J-CROS 1402 HN, IJROBP (adenoid cystic carcinoma) | 289 patients with head and neck ACC | 2-year local control 88%, 2-year survival 94%, estimated 5-year survival 74% |
| J-CROS 1402 HN, IJROBP (mucosal melanoma) | 260 patients, nose, sinuses, mouth, pharynx | 2-year local control 83.9%, 2-year survival 69.4% |
| Kaneko et al., In Vivo 2021 | 33 oropharyngeal non-squamous cases (23 were T4) | 5-year local control 86.8%, 5-year survival 77.2% |
| Akbaba et al., Frontiers in Oncology 2020 (Germany) | 207 major salivary gland ACC, IMRT plus carbon ion boost | 5-year local control 84%, 10-year survival 73% |
Both J-CROS teams concluded that carbon ion therapy is a promising treatment option. In the melanoma study, patients who also received chemotherapy had better survival, so Japanese centers consider combining drug therapy depending on the case. The oropharyngeal study achieved results comparable to surgical series despite mostly T4 tumors, and the German study reported higher local control than photon data with moderate toxicity.
Side effects depend on how close the tumor is to the eye, jawbone and mucosa. Oral mucositis and skin reactions are common during treatment and usually heal afterwards. Late effects can include jaw osteonecrosis or reduced vision on the treated side; centers reduce risk with pre-treatment dental care and image-based planning and follow patients after they return home. See Carbon ion therapy side effects.
How many sessions, and how long will I stay in Japan?
QST Hospital lists 4 weeks of treatment for head and neck cancer in its overseas patient guide. The most common regimen in the multicenter studies was 16 sessions (57.6–64.0 Gy (RBE)). QST's Japanese materials list about 4 weeks for nasal, sinus and salivary gland cancers and about 3 weeks for lacrimal gland cancer.
| Step | What happens | Time |
|---|---|---|
| 1. Record review | Records sent through a registered medical coordinator; physicians assess eligibility | Before travel |
| 2. First visit and preparation | Examination, face/neck immobilization mask, CT and MRI, dental check if needed | A few days |
| 3. Treatment planning | Beam design (you may go home and return by the day before treatment) | About 1–2 weeks |
| 4. Irradiation | Once a day on weekdays, usually 16 sessions | About 4 weeks |
| 5. After returning home | Regular imaging follow-up with local and Japanese hospitals | Several years |
Eating can become uncomfortable from mucositis late in the course, so lodging where soft food is easy to prepare and a companion's schedule help. Compare hospital contact points in 7 carbon ion therapy hospitals in Japan.
How much does head and neck carbon ion therapy cost?
Japanese residents have had public insurance for malignant head and neck tumors since April 2018, but overseas patients without Japanese insurance pay the hospital's self-pay fee. The carbon ion fee is a flat amount per course regardless of the number of sessions.
| Item | QST Hospital (Chiba), overseas patients |
|---|---|
| Carbon ion radiotherapy | 5.786 million yen (tax included) |
| Hospital stay, consultations, tests | 33 yen per medical fee point (tax included) |
| Separate costs | Medical coordinator fee, flights, lodging, interpreting |
Amounts are from QST Hospital's overseas patient page (accessed 21 October 2026) and may change with exchange rates and revisions. For other hospitals and total costs including stay, see Carbon ion therapy cost comparison.
Which Japanese carbon ion center to contact first with your records, and what the total may be — ask us (+82-2-517-5117).
Documents and questions to prepare before a consultation
Japanese hospitals first review records from overseas patients to decide eligibility. QST Hospital asks for inquiries through a registered guarantor (a medical coordinator or travel agency). For head and neck cancer, these speed up the review:
- Referral letter: diagnosis, stage (T, N, M) and treatment history (English translation)
- Pathology report: histology (ACC, melanoma, adenocarcinoma, squamous, etc.)
- Imaging CD (DICOM): head and neck MRI and CT within 1–2 months, PET-CT or chest CT for metastasis
- Endoscopy images and findings: important for nasal and pharyngeal tumors
- Previous surgery and radiation records: extent, radiation site and dose, dental implants or metal prostheses
- Current symptoms: vision or double vision, nasal blockage or bleeding, swallowing and speech
Write down questions too: Which option better preserves function, surgery or carbon ions? Is chemotherapy or immunotherapy needed alongside? How far is the tumor from the optic nerve? Where will follow-up scans be done after returning home? See Japanese institutions for each hospital's profile.
Frequently asked questions
Can head and neck squamous cell carcinoma be treated with carbon ions?
Squamous cell carcinoma of the oral cavity, pharynx and larynx responds well to conventional radiation, so QST excludes it. Other sites close to critical structures such as the optic nerve, where conventional radiation cannot give enough dose, may be considered.
How effective is carbon ion therapy for adenoid cystic carcinoma?
A Japanese multicenter study of 289 patients reported 88% 2-year local control and 94% 2-year survival, and a German study of 207 patients reported 84% 5-year local control. Results vary with tumor size and location, so an individual assessment is needed.
Is the cost for foreign patients the same as for Japanese patients?
Japanese patients have been covered by public insurance since 2018, while overseas patients pay out of pocket: at QST Hospital, 5.786 million yen (tax included) for carbon ion therapy plus consultation and test fees.
Can recurrent head and neck cancer be treated?
Recurrence after surgery can be eligible; recurrence in a previously irradiated area is judged individually based on the earlier dose and normal tissue condition. Please send previous treatment records.
Related articles
Wondering if carbon ion therapy is possible for you, and what it costs?
We help you prepare consultations with Japanese institutions and provide medical interpreting.
Free consultationCall +82-2-517-5117Sources
- QST Hospital — Head and neck cancer (indications for carbon ion radiotherapy)
- QST Hospital — Carbon ion radiotherapy for patients from abroad (fees and application)
- A Multicenter Study of Carbon-Ion Radiotherapy for Adenoid Cystic Carcinoma of the Head and Neck (J-CROS 1402 HN). Int J Radiat Oncol Biol Phys
- A Multicenter Study of Carbon-Ion Radiotherapy for Mucosal Melanoma of the Head and Neck (J-CROS 1402 HN). Int J Radiat Oncol Biol Phys
- Kaneko T, et al. Multicenter Study of Carbon-ion Radiotherapy for Oropharyngeal Non-squamous Cell Carcinoma. In Vivo 2021;35:2239-2245
- Akbaba S, et al. Large German Multicenter Experience on 207 Patients With Adenoid Cystic Carcinoma of the Major Salivary Glands. Front Oncol 2020;10:593379
- QST Hospital — Indicated diseases and results of carbon ion radiotherapy (Japanese)
- QST Hospital — Carbon ion therapy overview, 2018 insurance coverage for head and neck tumors (Japanese)
General information based on public sources; not a substitute for diagnosis or treatment. Eligibility is decided by the treating physicians. Written by the FTH editorial team.