Early clinical outcomes of helical tomotherapy/intensity-modulated proton therapy combination in nasopharynx cancer.

Abstract

This study aimed to evaluate the feasibility of combining helical tomotherapy (HT) and intensity-modulated proton therapy (IMPT) in treating patients with nasopharynx cancer (NPC). From January 2016 to March 2018, 98 patients received definitive radiation therapy (RT) with concurrent chemotherapy (CCRT). Using simultaneous integrated boost and adaptive re-plan, 3 different dose levels were prescribed: 68.4 Gy in 30 parts to gross tumor volume (GTV), 60 Gy in 30 parts to high-risk clinical target volume (CTV), and 36 Gy in 18 parts to low-risk CTV. In all patients, the initial 18 fractions were delivered by HT, and, after rival plan evaluation on the adaptive re-plan, the later 12 fractions were delivered either by HT in 63 patients (64.3%, HT only) or IMPT in 35 patients (35.7%, HT/IMPT combination), respectively. Propensity-score matching was conducted to control differences in patient characteristics. In all patients, grade ≥ 2 mucositis (69.8% vs 45.7%, P = .019) and grade ≥ 2 analgesic usage (54% vs 37.1%, P = .110) were found to be less frequent in HT/IMPT group. In matched patients, grade ≥ 2 mucositis were still less frequent numerically in HT/IMPT group (62.9% vs 45.7%, P = .150). In univariate analysis, stage IV disease and larger GTV volume were associated with increased grade ≥ 2 mucositis. There was no significant factor in multivariate analysis. With the median 14 month follow-up, locoregional and distant failures occurred in 9 (9.2%) and 12 (12.2%) patients without difference by RT modality. In conclusion, comparable early oncologic outcomes with more favorable acute toxicity profiles were achievable by HT/IMPT combination in treating NPC patients.

• Authors: Seung Gyu Park, Yong Chan Ahn, Dongryul Oh, Jae Myoung Noh, Sang Gyu Ju, Dongyeol Kwon, Kwanghyun Jo, Kwangzoo Chung, Eunah Chung, Woojin Lee, Seyjoon Park
• Journal: Cancer science (Cancer Sci) Vol. 110 Issue 9 Pg. 2867-2874 (Sep 2019) ISSN: 1349-7006 [Electronic] England
• PMID: 31237050 (Publication Type: Journal Article)
• Copyright: © 2019 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Chemical References

• Radiation-Sensitizing Agents
• Cisplatin

Topics

• Adult
• Aged
• Chemoradiotherapy (adverse effects, methods)
• Cisplatin (adverse effects, therapeutic use)
• Feasibility Studies
• Female
• Follow-Up Studies
• Humans
• Male
• Middle Aged
• Mucositis (epidemiology, etiology)
• Nasopharyngeal Neoplasms (mortality, therapy)
• Neoplasm Recurrence, Local (epidemiology, prevention & control)
• Proton Therapy (adverse effects, methods)
• Radiation Injuries (epidemiology, etiology)
• Radiation-Sensitizing Agents (therapeutic use)
• Radiotherapy Dosage
• Radiotherapy, Intensity-Modulated (adverse effects, methods)
• Treatment Outcome
• Young Adult