Nobuteru Kubo1, Yoshiki Kubota2, Hidemasa Kawamura2, Takahiro Oike2, Makoto Sakai2, Takuya Kumazawa2, Yuhei Miyasaka2, Shohei Okazaki2, Daijiro Kobayashi2, Hiro Sato2, Tatsuji Mizukami2, Atsushi Musha2, Katsuyuki Shirai3, Jun-Ichi Saitoh4, Satoshi Yokoo5, Kazuaki Chikamatsu6, Tatsuya Ohno2, Takashi Nakano2. 1. Gunma University Heavy Ion Medical Center, Maebashi, Japan. Electronic address: kubo0330@gmail.com. 2. Gunma University Heavy Ion Medical Center, Maebashi, Japan. 3. Gunma University Heavy Ion Medical Center, Maebashi, Japan; Department of Radiology, Saitama Medical Center, Jichi Medical University, Omiya-ku, Japan. 4. Gunma University Heavy Ion Medical Center, Maebashi, Japan; Department of Radiation Oncology, University of Toyama, Faculty of Medicine, Japan. 5. Department of Oral and Maxillofacial Surgery, and Plastic Surgery, Gunma University Graduate School of Medicine, Maebashi, Japan. 6. Department of Otolaryngology-Head and Neck Surgery, Gunma University Graduate School of Medicine, Maebashi, Japan.
Abstract
BACKGROUND AND PURPOSE: Little information is available on the risk factors for nasolacrimal duct obstruction after radiotherapy for head and neck tumors. We investigated the incidence and predictive dosimetric parameters for nasolacrimal duct obstruction following carbon-ion radiotherapy for head and neck tumors. MATERIALS AND METHODS: Twenty-eight patients with head and neck non-squamous cell carcinoma were analyzed in this single-institution prospective study. More than half of the tumors were located in the nasal cavity and maxillary sinus. Carbon-ion radiotherapy consisting of 57.6 or 64.0 Gy(relative biological effectiveness; RBE) in 16 fractions was administered. Nasolacrimal duct obstruction was recorded according to Common Terminology Criteria for Adverse Events version 4.0. Cutoff values were determined using receiver operating characteristic (ROC) curve analysis. VX indicates the volume irradiated with X Gy(RBE). RESULTS: The median follow-up period was 60.3 months. Incidences of Grade 1 and 2 nasolacrimal duct obstructions were 46% (13/28) and 7% (2/28), respectively; no Grade 3 or greater toxicities were recorded. Throughout the dose range, the volumes of the irradiated nasolacrimal ducts were significantly higher in the obstruction-positive patients than in the obstruction-negative patients (p < 0.001 for V10, V20, V30, V40, V50, and V60). Cutoff values determined by the ROC curve analysis classified the obstruction-positive patients with an accuracy of >96% over the entire range of V10-V60. CONCLUSION: The incidence and predictive dosimetric parameters for nasolacrimal duct obstruction after carbon-ion radiotherapy were demonstrated in a prospective cohort. These data should help optimize carbon-ion radiotherapy treatments for patients with head and neck tumors.
BACKGROUND AND PURPOSE: Little information is available on the risk factors for nasolacrimal duct obstruction after radiotherapy for head and neck tumors. We investigated the incidence and predictive dosimetric parameters for nasolacrimal duct obstruction following carbon-ion radiotherapy for head and neck tumors. MATERIALS AND METHODS: Twenty-eight patients with head and neck non-squamous cell carcinoma were analyzed in this single-institution prospective study. More than half of the tumors were located in the nasal cavity and maxillary sinus. Carbon-ion radiotherapy consisting of 57.6 or 64.0 Gy(relative biological effectiveness; RBE) in 16 fractions was administered. Nasolacrimal duct obstruction was recorded according to Common Terminology Criteria for Adverse Events version 4.0. Cutoff values were determined using receiver operating characteristic (ROC) curve analysis. VX indicates the volume irradiated with X Gy(RBE). RESULTS: The median follow-up period was 60.3 months. Incidences of Grade 1 and 2 nasolacrimal duct obstructions were 46% (13/28) and 7% (2/28), respectively; no Grade 3 or greater toxicities were recorded. Throughout the dose range, the volumes of the irradiated nasolacrimal ducts were significantly higher in the obstruction-positive patients than in the obstruction-negative patients (p < 0.001 for V10, V20, V30, V40, V50, and V60). Cutoff values determined by the ROC curve analysis classified the obstruction-positive patients with an accuracy of >96% over the entire range of V10-V60. CONCLUSION: The incidence and predictive dosimetric parameters for nasolacrimal duct obstruction after carbon-ion radiotherapy were demonstrated in a prospective cohort. These data should help optimize carbon-ion radiotherapy treatments for patients with head and neck tumors.
Authors: Piero Fossati; Ana Perpar; Markus Stock; Petra Georg; Antonio Carlino; Joanna Gora; Giovanna Martino; Eugen B Hug Journal: Int J Part Ther Date: 2021-06-25