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In 1994 a Phase I/II clinical study on carbon ion radiotherapy was begun at NIRS using HIMAC, which was then the world's only heavy ion accelerator complex dedicated to medical use in a hospital environment. Among several types of ion species, we have chosen carbon ions for cancer therapy because they had the most optimal properties in terms of possessing, both physically and biologically, the most effective dose-localization in the body. The purpose of the clinical study was to investigate the efficacy of carbon ion radiotherapy against a variety of tumors as well as to develop effective techniques for delivering an efficient dose to the tumor. The RBE of carbon ions was estimated to be 2.0 to 3.0 along the SOBP for acute skin reactions. As of August 2006, a total of 2,867 patients had been entered into Phase I/II or Phase II studies and analyzed for toxicity and local tumor response. The results have shown that carbon ion radiotherapy has the potential ability to provide a sufficient dose to the tumor with acceptable morbidity in the surrounding normal tissues. Tumors that appear to respond favorably to carbon ions include locally advanced tumors and those with histologically non-squamous cell type of tumors such as adenocarcinoma, adenoid cystic carcinoma, malignant melanoma, hepatoma, and bone/soft tissue sarcoma. By taking advantage of the biological and physical properties of high-LET radiation, the efficacy of treatment regimens with small fractions in short treatment times has been confirmed for almost all types of tumors in carbon ion radiotherapy.

BACKGROUNDThe authors performed a long‐term follow‐up study to evaluate the efficacy and late toxicity of high‐dose rate intracavitary brachytherapy (HDR‐ICBT) for cervical carcinoma.METHODSFrom 1968 to 1986, 1148 patients with Stage IB to IVB squamous cell carcinoma of the cervix (staging was performed according to the International Federation of Gynecology and Obstetrics) were treated with a combination of external beam radiotherapy (EBRT) and HDR‐ICBT. For patients with early‐stage disease, 20 gray (Gy) of EBRT was delivered to the whole pelvis, followed by 24 Gy/4 fractions of HDR‐ICBT and 30 Gy of central‐shielding EBRT. For patients with advanced‐stage disease, 20–40 Gy of whole pelvic EBRT was administered, followed by 24 Gy/4 fractions of ICBT and 30–10 Gy of central‐shielding EBRT. The overall treatment time was approximately 6 weeks. Among survivors, the follow‐up rate was 98% and the median follow‐up duration was 22 years.RESULTSThe 10‐year pelvic tumor control rates were 93% for patients with Stage IB disease, 82% for patients with Stage II disease, and 75% for patients with Stage III disease. The 10‐year overall and cause‐specific survival rates were 74% and 89% for patients with Stage IB disease, 52% and 74% for patients with Stage II disease, and 42% and 59% for patients with Stage III disease, respectively. The 10‐year actuarial rates of major complications were 4.4% in the rectosigmoid colon, 0.9% in the bladder, and 3.3% in the small intestines.CONCLUSIONSThe results of the current study suggest that the combination of EBRT and HDR‐ICBT according to the authors' protocol provided outcomes that were comparable to those of the conventional low‐dose rate brachytherapy with acceptable rates of late complications in the treatment of cervical carcinoma. Cancer 2005. © 2004 American Cancer Society.

Carbon ion radiotherapy offers superior dose conformity in the treatment of deep-seated malignant tumours compared with conventional X-ray therapy. In addition, carbon ion beams have a higher relative biological effectiveness compared with protons or X-ray beams. The algorithm of treatment planning and beam delivery system is tailored to the individual parameters of the patient. The present article reviews the available literatures for various disease sites including the head and neck, skull base, lung, liver, prostate, bone and soft tissues and pelvic recurrence of rectal cancer as well as physical and biological properties.

Herein, we investigate the long-term clinical outcomes for cervical cancer patients treated with in-room computed tomography–based brachytherapy. Eighty patients with Stage IB1–IVA cervical cancer, who had undergone treatment with combined 3D high-dose rate brachytherapy and conformal radiotherapy between October 2008 and May 2011, were retrospectively analyzed. External beam radiotherapy (50 Gy) with central shielding after 20–40 Gy was performed for each patient. Cisplatin-based chemotherapy was administered concurrently to advanced-stage patients aged ≤75 years. Brachytherapy was delivered in four fractions of 6 Gy per week. In-room computed tomography imaging with applicator insertion was performed for treatment planning. Information from physical examinations at diagnosis, and brachytherapy and magnetic resonance imaging at diagnosis and just before the first brachytherapy session, were referred to for contouring of the high-risk clinical target volume. The median follow-up duration was 60 months. The 5-year local control, pelvic progression-free survival and overall survival rates were 94%, 90% and 86%, respectively. No significant differences in 5-year local control rates were observed between Stage I, Stage II and Stage III–IVA patients. Conversely, a significant difference in the 5-year overall survival rate was observed between Stage II and III–IVA patients (97% vs 72%; P = 0.006). One patient developed Grade 3 late bladder toxicity. No other Grade 3 or higher late toxicities were reported in the rectum or bladder. In conclusion, excellent local control rates were achieved with minimal late toxicities in the rectum or bladder, irrespective of clinical stage.

Favorable overall outcomes of CIRT for prostate cancer were suggested by the analysis of the first multi-institutional data.

Carbon-ion RT is a promising treatment option for MMHN.

Carbon ion radiotherapy (C-ion RT) offers superior dose conformity in the treatment of deep-seated tumors compared with conventional X-ray therapy. In addition, carbon ion beams have a higher relative biological effectiveness compared with protons or X-ray beams. C-ion RT for the first patient at Gunma University Heavy Ion Medical Center (GHMC) was initiated in March of 2010. The major specifications of the facility were determined based on the experience of clinical treatments at the National Institute of Radiological Sciences (NIRS), with the size and cost being reduced to one-third of those at NIRS. The currently indicated sites of cancer treatment at GHMC are lung, prostate, head and neck, liver, rectum, bone and soft tissue. Between March 2010 and July 2011, a total of 177 patients were treated at GHMC although a total of 100 patients was the design specification during the period in considering the optimal machine performance. In the present article, we introduce the facility set-up of GHMC, including the facility design, treatment planning systems, and clinical preparations.