Hiroaki Ikawa

Feasibility of carbon ion radiotherapy for locally advanced sinonasal adenocarcinoma.

BACKGROUND AND PURPOSE To evaluate the safety and efficacy of carbon ion radiotherapy (CIRT) for locally advanced sinonasal adenocarcinoma. MATERIAL AND METHODS Twenty-two patients with sinonasal adenocarcinoma were treated with CIRT. CIRT was the primary treatment for 16 patients. Four patients received CIRT for local recurrence after surgery and two for residual tumour after surgery or chemotherapy. At the start of CIRT, 1 patient had T-classification (T) 2 disease, 2 had T3 disease, 5 had T4a disease, and 14 had T4b disease. Fourteen patients were treated with 57.6 Gy equivalent (GyE)/16 fractions, and 8, with 64.0 GyE/16 fractions. RESULTS The median follow-up period was 43 months for all patients. The 3-year local control and loco-regional control rates for all patients were 76.9% (95% confidence interval [CI]=56.7-97.1%) and 61.3% (95% CI=38.5-84.1%), respectively. The 3-year overall survival and disease-specific survival rates were 59.1% (95% CI=38.6-79.6%) and 65.6% (95% CI=44.9-86.3%), respectively. Acute reactions of grade 3 of the skin and mucosa were observed in 2 and 4 patients, respectively. Late reactions included lateral visual loss (5 patients), mucosal ulceration (1 patient), and brain necrosis with clinical symptoms (1 patient). In the 5 patients who developed visual loss, the optic nerve was close to the tumour. CONCLUSIONS CIRT was effective and generally safe for locally advanced sinonasal adenocarcinoma.

Carbon ion radiotherapy for locally advanced squamous cell carcinoma of the external auditory canal and middle ear

The prognosis of advanced squamous cell carcinoma (SCC) of the external auditory canal and middle ear remains poor. Carbon ion radiotherapy (C‐ion RT) has shown promise for locally advanced head and neck cancer. Therefore, we evaluated the safety and efficacy of C‐ion RT for locally advanced SCC of the external auditory canal and middle ear.

Evaluation of the safety and efficacy of carbon ion radiotherapy for locally advanced adenoid cystic carcinoma of the tongue base.

Most cases of adenoid cystic carcinoma (ACC) of the tongue base are radioresistant, and are diagnosed in the advanced stage. Therefore, we evaluated the safety and efficacy of carbon ion radiotherapy (C‐ion RT) for locally advanced ACC of the tongue base.

Definitive carbon-ion radiotherapy for locally advanced parotid gland carcinomas

The purpose of this study was to present our evaluation of the safety and efficacy of carbon‐ion radiotherapy (C‐ion RT) for locally advanced parotid gland carcinomas.

Prognostic factors of adenoid cystic carcinoma of the head and neck in carbon-ion radiotherapy: The impact of histological subtypes

PURPOSE The aim of this study was to evaluate the effect of histological subtypes of head and neck adenoid cystic carcinoma (ACC) on the results of carbon-ion radiotherapy (CIRT). MATERIAL AND METHODS Of the 113 patients with ACC who were treated with CIRT between December 2006 and July 2013, 100 patients with identified histological subtypes were enrolled in this study. CIRT at a total dose of 57.6 or 64.0Gy (RBE) was administered in 16 fractions. Histological grading was defined as the presence or absence of a solid growth pattern. RESULTS Median follow-up was 60 months. 5-Year local control (LC), overall survival (OS) and distant metastasis free survival (DMFS) of all patients were 68.6%, 74.8% and 65.7%, respectively. On multivariate analysis, the prescribed dose (p=0.001) and gross tumor volume (p=0.002) were significant independent risk factors for LC. No significant difference for local control of solid/non-solid growth patterns was found (p=0.093). Solid growth pattern was an independent risk factor for both OS (p=0.033) and DMFS (p=0.024). CONCLUSIONS CIRT appears able to locally control solid growth pattern ACC in the head and neck. Improved intervention is needed to extend DMFS and OS.

Long-term outcomes after carbon-ion radiotherapy for oral mucosal malignant melanoma.

Abstract Oral mucosal malignant melanoma (OMM) is extremely rare and has a poor prognosis. Owing to its rarity, it has not yet been possible to establish an optimal treatment modality. The objective of this study was to evaluate the long-term efficacy of carbon-ion radiotherapy (C-ion RT) for OMM. Between 1997 and 2013, 19 patients with OMM were treated with C-ion RT alone. Patient ages ranged from 44 to 84 years (median, 69 years). Nine men and 10 women were included. OMMs were restaged in accordance with the seventh edition of the tumour/node/metastasis (TNM) Staging System of the International Union Against Cancer. Before treatment, 14 patients had T3 disease and 5 had T4a disease. Three patients were classified as having N1 disease. All patients were classified as having M0. The hard palate was the most frequently involved oral subsite. All patients were treated with 57.6 Gy (relative biological effectiveness) in 16 fractions. The median follow-up period was 61 months (range, 8–190 months). The 5-year local control, overall survival and progression-free survival rates were 89.5%, 57.4% and 51.6%, respectively. For local control and overall survival, T classification was found to be a significant prognostic factor. Grade 2 and 3 osteoradionecrosis was observed in three and four patients, respectively. The presence of teeth within the planning target volume was a significant risk factor for developing osteoradionecrosis. C-ion RT was an effective treatment option with acceptable toxicity for OMM.

Efficacy and safety of carbon-ion radiotherapy for lacrimal gland carcinomas with extraorbital extension: a retrospective cohort study

Purpose To evaluate the efficacy and safety of carbon-ion radiotherapy (CIRT) for patients with lacrimal gland carcinomas (LGCs) with extraorbital extension Results The median follow-up period was 53.7 months. The 5-year local control and overall survival rates were 62% and 65%, respectively. Regarding late toxicities, 12 patients (36.4%) developed Grade 4 optic nerve disorders, including visual losses of the diseased side (N = 8; 66.7%), and 1 patient (3.0%) developed a Grade 3 optic nerve disorder. Three patients (9.0%) developed Grade 3 cataracts, 3 (9.0%) developed glaucoma, and 1 (3.0%) developed retinopathy. Two patients (6.1%) had Grade 4 central nervous system necrosis. No Grade 5 late toxicities were observed. The 5-year preservation rate of the ipsilateral eyeball was 86%. Conclusion Definitive CIRT is effective for LGCs with extraorbital extension with acceptable toxicity. Methods Thirty-three patients treated with CIRT at our institution were analyzed. Sixteen patients (48.5%) had adenoid cystic carcinoma, 8 (24.2%) had adenocarcinoma not otherwise specified, and 9 (27.3%) had other types of the disease. Thirty patients (90.9%) had T4c tumors. The prescribed doses were 57.6 Gy (relative biological effectiveness [RBE]) (N = 18; 54.5%) and 64.0 Gy (RBE) (N = 15; 45.5%) in 16 fractions.

A retrospective multicenter study of carbon‐ion radiotherapy for major salivary gland carcinomas: Subanalysis of J‐CROS 1402 HN

A retrospective multicenter study was carried out to assess the clinical outcomes of carbon‐ion radiotherapy for head and neck malignancies (Japan Carbon‐Ion Radiation Oncology Study Group [J‐CROS] study: 1402 HN). We evaluated the safety and efficacy of carbon‐ion radiotherapy in patients with major salivary gland carcinoma. Sixty‐nine patients treated with carbon‐ion radiotherapy at four Japanese institutions were analyzed. Thirty‐three patients (48%) had adenoid cystic carcinomas, 10 (14%) had mucoepidermoid carcinomas, and 26 (38%) had other disease types. Three patients (4%) had T1 disease, 8 (12%) had T2, 25 (36%) had T3, and 33 (48%) had T4. The median radiation dose was 64 Gy (relative biological effectiveness) in 16 fractions. The median gross tumor volume was 27 mL. The median follow‐up period was 32.7 months. The 3‐year local control rate and overall survival rate were 81% and 94%, respectively. Regarding acute toxicities, seven patients had grade 3 mucositis and seven had grade 3 dermatitis. Regarding late toxicities, one patient had grade 3 dysphagia and one had a grade 3 brain abscess. No grade 4 or worse late reactions were observed. In conclusion, definitive carbon‐ion radiotherapy was effective with acceptable toxicity for major salivary gland carcinomas.

The Efficacy of a Custom-Made Mouthpiece With Spacer to Reduce Osteoradionecrosis in Carbon-Ion Radiation Therapy for Tongue-Based Tumor

Summary There is risk of mandibular osteoradionecrosis following external radiotherapy to tumors at the base of the tongue. To date, no report evaluates sparing of the mandibular bone offered by use of spacers. Here, we introduce and evaluate a custom-made mouthpiece employing a spacer for reduction of osteonecrosis following carbon-ion radiotherapy of tongue base tumors.

A custom-made mouthpiece incorporating tongue depressors and elevators to reduce radiation-induced tongue mucositis during carbon-ion radiation therapy for head and neck cancer

We introduce a custom-made mouthpiece for carbon-ion radiation therapy for head and neck malignancy. The mouthpiece incorporates either a tongue depressor or elevator depending on tumor location. The risk of tongue mucositis may be reduced without compromising therapeutic efficacy through mouthpiece shaping.