A Retrospective Multicenter Study of Carbon Ion Radiotherapy for Locally Advanced Olfactory Neuroblastomas

Abstract

Abstract. The purpose was to evaluate efficacy and safety of carbon ion radiotherapy (C-ion RT) in patients with locally advanced olfactory neuroblastomas (ONBs). This study was a sub-analysis of the Japan Carbon-Ion Radiation Oncology Study Group Study (1402 HN, UMIN000024473). Clinical data of T4 ONBs treated with C-ion RT at fourOlfactory neuroblastoma (ONB) of the head and neck is a rare malignant tumour that arises from the olfactory neuroepithelium in the upper nasal cavity with extension into the skull base, into the orbit and to the intracranial space (1, 2). Surgery is considered a curative treatment for localized ONB, while postoperative radiotherapy (RT) is necessary for advanced ONBs. Definitive RT alone is considered insufficient therapy for ONBs (3). In advanced cases, intracranial extension may pose a surgical challenge (4). Surgical resection followed by postoperative RT is associated with reduced local recurrence (5).Although ONB has been traditionally regarded as a radioresistant tumour, RT has widely been used as part of the treatment algorithm in adjuvant and definitive settings.Compared to photons, carbon ions (C-ions) offer a higher linear energy transfer and greater relative biological effectiveness (RBE) and therefore provide a higher probability of tumour control. The physical characteristics of C-ions, such as their Bragg peak and small lateral scattering, are theoretically superior to those of photons in that C-ions can allow a more localized delivery of the radiation dose.This study is the first report for ONBs treated by C-ion RT. C-Ion RT for various head and neck radioresistant malignancies has shown excellent results. Jingu et al. reported clinical results of 37 patients with malignant melanoma of the head and neck who received C-ion RT with concurrent chemotherapy. The 3-year local control (LC) and overall survival (OS) rates were 81.1% and 65.3%, respectively (6). Koto et al. reported 3-year LC and OS rates of 76.9% and 59.1%, respectively, in 22 patients with locally advanced sinonasal adenocarcinoma + reated with C-ion RT (7). Therefore, C-ion RT might be a useful and potentially curative option for unresectable head and neck tumours, including ONBs.In November 2003, following a clinical trial, the Ministry of Health, Labour and Welfare in Japan approved C-ion RT as a highly advanced medical technology. As of the end of 2014, there were four C-ion facilities functioning in Japan

Advanced Radiation Techniques in the Treatment of Esthesioneuroblastoma: A 7-Year Single-Institution’s Clinical Experience

“…Most of the published cases are described in case studies or a single-institution’s retrospective analyses with small cohorts. To our knowledge, the biggest cohorts describing particle therapy in the treatment of ENB consist of 42 patients treated with protons from 1999 to 2012 [ 22 ] and 21 patients treated with carbon ions from 2003 to 2014 [ 23 ]. Generally, the biggest patient cohorts are known from database analyses, in which different radiation techniques are usually not further described, for example, recently in a National Cancer Database analysis investigating 931 cases of ENB [ 13 ].…”

A retrospective multicenter study of carbon‐ion radiotherapy for external auditory canal and middle ear carcinomas

“…For central nervous system necrosis induced by CIRT, a previous study demonstrated that the brain volume receiving >50 Gy was a significant risk factor for the development of grade 2 or higher radiation-induced brain injury . 20 Future studies should focus on using new technical methods such as scanning irradiation or intensity-modulated particle therapy, since they improve dose distribution [21][22][23] and may therefore reduce the incidence of central nervous system necrosis. Meanwhile, our results demonstrated that there was no grade 2 or higher osteoradionecrosis, although Koto et al reported grade 3 temporal bone necrosis with skin ulcers in two patients receiving CIRT .…”

“…Our multicenter study (J-CROS 1402 HN) showed that CIRT was effective and safe for head and neck malignancies, particularly including radioresistant tumors. [9][10][11][12][23][24][25] Since April 2018, the public health insurance system in Japan has covered CIRT for head and neck malignancies, with the exception of radiosensitive oral, laryngeal, and pharyngeal squamous cell carcinoma.…”

Dosimetric parameters predictive of nasolacrimal duct obstruction after carbon-ion radiotherapy for head and neck carcinoma

“…Non-squamous cell carcinoma (NSCC) in the head and neck region is resistant to photon therapy and chemotherapy, and therefore the standard therapy for this disease remains a subject of debate. Previous studies indicated that carbon-ion radiotherapy provides favorable local control and survival for head and neck NSCCs [1][2][3][4]. Differing from squamous cell carcinomas of the head and neck region, which are predominantly located in the oral cavity and pharynx, more than 50% of NSCCs arising in the head and neck region are located in the sinonasal cavity [5].…”

“…Cumulative incidence of Grade 1 or higher nasolacrimal duct obstruction stratified by (a) a V40 value of 0.08 cm3 , or (b) primary tumor site. P-values calculated by log-rank test are shown.…”