Carbon Ion Therapy After TACE for Liver Cancer: 3-Year Results, Cost

Carbon ion therapy after TACE is an option for people with hepatocellular carcinoma (HCC) whose tumor remains or regrows in the same place after transarterial chemoembolization. In a study from Gunma University Heavy Ion Medical Center published in ESMO Gastrointestinal Oncology in January 2026, 99 patients treated with the carbon ion therapy machine had a 3-year local control rate of 90.7% and a 3-year overall survival rate of 70.3%. Liver function scores did not worsen significantly after treatment. This is a retrospective study based on records of patients treated in routine care. Below we summarize the results, the conditions linked to better outcomes, the schedule and costs for international patients. To find out whether your scans and liver tests make you a candidate, ask us about eligibility and cost.

Why consider carbon ion therapy for HCC remaining after TACE?

TACE delivers anticancer drugs and embolic material into the artery feeding the tumor and blocks its blood supply. It is widely used for HCC that cannot be removed surgically, but sometimes the tumor is not fully treated or regrows months later. Repeating the procedure many times can gradually reduce the remaining liver function, so many patients look for another approach.

Carbon ion therapy accelerates carbon nuclei to close to the speed of light and aims them at the tumor. Carbon ion beams release most of their energy at a set depth and then stop (the Bragg peak), giving a strong dose to the tumor and a low dose to the surrounding normal liver. See What Is Carbon Ion Therapy? for details. Unlike TACE, which works through the blood vessels, the beam is shaped to the tumor from outside the body, offering a different route for tumors that TACE has not controlled.

Gunma study of 99 patients: 3-year local control 90.7%

The authors are radiation oncologists and hepatobiliary surgeons from Gunma University Heavy Ion Medical Center and other Japanese hospitals. They analyzed 99 patients (106 lesions) with residual or recurrent HCC after TACE treated with carbon ions between 2010 and 2021. Median follow-up was 38 months.

Outcome	3-year result	Meaning
Local control	90.7%	Treated tumors that did not regrow
Overall survival	70.3%	Patients alive at 3 years
Progression-free survival	34.8%	Free of any new lesion, including elsewhere in the liver
Liver function (Child-Pugh, ALBI)	No significant decline	Scores before and after treatment

Nine out of ten treated tumors did not regrow over three years. Progression-free survival is lower than local control because HCC tends to arise in new parts of the liver, so regular scans continue after treatment and new lesions can be treated with TACE or other options. The authors concluded that carbon ion therapy is a safe and effective salvage treatment for TACE-refractory HCC.

For other situations, see carbon ion therapy for liver tumors over 10 cm and carbon ion therapy instead of liver surgery.

Is liver function preserved? Side effects and care

For patients who have had several TACE sessions, the main concern is remaining liver function. In this study, Child-Pugh and ALBI scores (based on albumin and bilirubin) did not deteriorate significantly after treatment, reflecting the low dose given to normal liver outside the tumor.

Severe late side effects were rare; hepatic encephalopathy was reported in two patients. Mild symptoms such as fatigue or skin redness can occur during treatment and usually settle afterward. Doctors check liver function with blood tests before and after treatment and manage changes with medication. See carbon ion therapy side effects.

Which patients did better?

Patients with tumors smaller than 3.5 cm and better baseline liver function (modified ALBI grade 2a or lower) had higher survival. Starting a consultation early, while the remaining tumor is small and liver function is good, is helpful.

Item	Favorable condition	What to bring
Remaining tumor size	Under 3.5 cm	Recent contrast CT or MRI
Liver function	Good ALBI grade (2a or lower)	Albumin, bilirubin, platelets
Number of lesions	Few lesions to treat	Radiology report with lesion sites
Prior treatment	Dates and number of TACE sessions	Procedure notes, discharge summary

Patients outside these conditions may still be eligible; Japanese physicians decide after reviewing images and test results. See liver cancer eligibility criteria.

Treatment machine, schedule and cost

Gunma University Heavy Ion Medical Center began treatment in March 2010. According to its English guide, carbon ions obtained from methane gas are first accelerated by a linear accelerator and then by a synchrotron to about 70% of the speed of light. It is a relatively compact prototype designed for wider deployment, with four treatment rooms using horizontal and vertical beams. Liver tumors are usually treated on a short schedule; the exact number of sessions depends on tumor location and distance from the stomach and bowel.

Hospital	Carbon ion fee for international patients	Additional costs	Reference
Gunma University Heavy Ion Medical Center	About 5 million yen, self-pay, regardless of number of sessions	Consultation, tests, admission, travel, accommodation, coordinator	English brochure, March 2025
QST Hospital (Chiba)	5.786 million yen (tax included)	Admission and tests (33 yen per medical fee point)	International patient guide, checked 28 Oct 2026
Osaka Heavy Ion Therapy Center	4.8 million yen + consumption tax	Consultation, tests, stay	Center fee guide, checked 28 Oct 2026

These amounts cover the carbon ion treatment itself; consultations, tests, living costs and interpreting are extra. International patients at Gunma first contact a cooperating medical coordinator company. See Gunma application process and Japanese institutions.

If you have TACE records and recent scans, we can check whether they are sufficient before sending them to a Japanese hospital. Contact us or call +82-2-517-5117.

What to prepare before a consultation

Proof of HCC diagnosis: pathology report or imaging diagnosis report
TACE records: dates, number of sessions, post-procedure imaging reports
Contrast CT or MRI within the last 3 months (CD or files) with reports
Blood tests: albumin, bilirubin, platelets, prothrombin time, tumor markers (AFP, PIVKA-II)
Ascites or encephalopathy history and current medication list

See documents checklist for formats and translation.

FAQ

Can I receive carbon ion therapy after several TACE sessions?

All patients in this study had residual or recurrent tumors after TACE. Current tumor size and liver function matter more than the number of sessions; Japanese physicians decide based on recent scans and blood tests.

Can TACE be repeated after carbon ion therapy?

If new lesions appear elsewhere in the liver, TACE or other treatments can be planned again. The order and timing are decided by the Japanese team together with your home physician.

Is Child-Pugh B eligible?

Japanese hospitals generally accept Child-Pugh A or B, but not C. Better liver function was linked to higher survival in this study, so early consultation is recommended.

How much does it cost, and does Japanese insurance apply?

International patients without Japanese insurance pay privately: about 5 million yen at Gunma (March 2025 brochure), 5.786 million yen at QST Hospital, and 4.8 million yen + tax at Osaka; tests and living costs are extra.

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.

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Sources

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.