Departamento de Radiologia, Disciplina de Oncologia, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Int J Radiat Oncol Biol Phys. 2012 Jan 1;82(1):270-5. doi: 10.1016/j.ijrobp.2010.10.012. Epub 2010 Dec 14.
Oral mucositis is a major complication of concurrent chemoradiotherapy (CRT) in head-and-neck cancer patients. Low-level laser (LLL) therapy is a promising preventive therapy. We aimed to evaluate the efficacy of LLL therapy to decrease severe oral mucositis and its effect on RT interruptions.
In the present randomized, double-blind, Phase III study, patients received either gallium-aluminum-arsenide LLL therapy 2.5 J/cm(2) or placebo laser, before each radiation fraction. Eligible patients had to have been diagnosed with squamous cell carcinoma or undifferentiated carcinoma of the oral cavity, pharynx, larynx, or metastases to the neck with an unknown primary site. They were treated with adjuvant or definitive CRT, consisting of conventional RT 60-70 Gy (range, 1.8-2.0 Gy/d, 5 times/wk) and concurrent cisplatin. The primary endpoints were the oral mucositis severity in Weeks 2, 4, and 6 and the number of RT interruptions because of mucositis. The secondary endpoints included patient-reported pain scores. To detect a decrease in the incidence of Grade 3 or 4 oral mucositis from 80% to 50%, we planned to enroll 74 patients.
A total of 75 patients were included, and 37 patients received preventive LLL therapy. The mean delivered radiation dose was greater in the patients treated with LLL (69.4 vs. 67.9 Gy, p = .03). During CRT, the number of patients diagnosed with Grade 3 or 4 oral mucositis treated with LLL vs. placebo was 4 vs. 5 (Week 2, p = 1.0), 4 vs. 12 (Week 4, p = .08), and 8 vs. 9 (Week 6, p = 1.0), respectively. More of the patients treated with placebo had RT interruptions because of mucositis (6 vs. 0, p = .02). No difference was detected between the treatment arms in the incidence of severe pain.
LLL therapy was not effective in reducing severe oral mucositis, although a marginal benefit could not be excluded. It reduced RT interruptions in these head-and-neck cancer patients, which might translate into improved CRT efficacy.
口腔黏膜炎是头颈部癌症患者同步放化疗（CRT）的主要并发症。低水平激光（LLL）治疗是一种有前途的预防治疗方法。我们旨在评估 LLL 治疗降低严重口腔黏膜炎的效果及其对 RT 中断的影响。
在本项随机、双盲、III 期研究中，患者在每次放射治疗前接受砷化镓铝 LLL 治疗 2.5 J/cm2 或安慰剂激光照射。合格的患者必须被诊断为口腔、咽、喉的鳞状细胞癌或未分化癌，或颈部有未知原发病灶的转移灶。他们接受辅助或根治性 CRT 治疗，包括常规 RT 60-70 Gy（范围 1.8-2.0 Gy/d，每周 5 次）和顺铂同步治疗。主要终点是第 2、4 和 6 周口腔黏膜炎的严重程度和因黏膜炎而导致的 RT 中断次数。次要终点包括患者报告的疼痛评分。为了将 3 或 4 级口腔黏膜炎的发生率从 80%降低到 50%，我们计划纳入 74 例患者。
共纳入 75 例患者，37 例患者接受了预防性 LLL 治疗。接受 LLL 治疗的患者平均接受的放射剂量更大（69.4 与 67.9 Gy，p =.03）。在 CRT 期间，接受 LLL 治疗与安慰剂治疗的患者中，3 或 4 级口腔黏膜炎的患者人数分别为 4 例与 5 例（第 2 周，p = 1.0）、4 例与 12 例（第 4 周，p =.08）和 8 例与 9 例（第 6 周，p = 1.0）。因黏膜炎而中断 RT 的患者中，接受安慰剂治疗的患者更多（6 例与 0 例，p =.02）。治疗组之间严重疼痛的发生率无差异。
尽管不能排除边缘获益，但 LLL 治疗并不能有效降低严重口腔黏膜炎的发生率。它减少了这些头颈部癌症患者的 RT 中断，这可能转化为 CRT 疗效的提高。
