Roesink Judith M, Schipper Maria, Busschers Wim, Raaijmakers Cornelis P J, Terhaard Chris H J
Department of Radiotherapy, University Hospital Utrecht, University Medical Center Utrecht, Utrecht, The Netherlands.
Int J Radiat Oncol Biol Phys. 2005 Nov 15;63(4):1006-9. doi: 10.1016/j.ijrobp.2005.04.023. Epub 2005 Jun 20.
To determine the most adequate parameter to measure the consequences of reducing the parotid gland dose.
One hundred eight patients treated with radiotherapy for various malignancies of the head and neck were prospectively evaluated using three methods. Parotid gland function was objectively determined by measuring stimulated parotid flow using Lashley cups and scintigraphy. To assess xerostomia-related quality of life, the head-and-neck cancer module European Organization for Research and Treatment of Cancer QLQ (Quality of Life Questionnaire) H&N35 was used. Measurements took place before radiotherapy and 6 weeks and 12 months after the completion of radiotherapy. Complication was defined for each method using cutoff values. The correlation between these complications and the mean parotid gland dose was investigated to find the best measure for parotid gland function.
For both flow and scintigraphy data, the best definition for objective parotid gland toxicity seemed to be reduction of stimulated parotid flow to < or =25% of the preradiotherapy flow. Of all the subjective variables, only the single item dry mouth 6 weeks after radiotherapy was found to be significant. The best correlation with the mean parotid gland dose was found for the stimulated flow measurements. The predictive ability was the highest for the time point 1 year after radiotherapy. Subjective findings did not correlate with the mean parotid dose.
Stimulated flow measurements using Lashley cups, with a complication defined as flow < or =25% of the preradiotherapy output, correlated best with the mean parotid gland dose. When reduction of the mean dose to the parotid gland is intended, the stimulated flow measurement is the best method for evaluating parotid gland function.
确定测量腮腺剂量降低后果的最适当参数。
前瞻性地采用三种方法对108例接受头颈部各种恶性肿瘤放射治疗的患者进行评估。通过使用拉什利杯测量刺激后的腮腺流量和闪烁扫描客观地确定腮腺功能。为评估与口干相关的生活质量，使用了欧洲癌症研究与治疗组织生活质量问卷（QLQ）头颈部癌症模块H&N35。在放疗前以及放疗结束后6周和12个月进行测量。使用临界值为每种方法定义并发症。研究这些并发症与腮腺平均剂量之间的相关性，以找到评估腮腺功能的最佳指标。
对于流量和闪烁扫描数据，客观腮腺毒性的最佳定义似乎是刺激后的腮腺流量降低至放疗前流量的≤25%。在所有主观变量中，仅发现放疗后6周的单项口干具有显著性。刺激流量测量与腮腺平均剂量的相关性最佳。放疗后1年时间点的预测能力最高。主观结果与腮腺平均剂量不相关。
使用拉什利杯进行刺激流量测量，将并发症定义为流量≤放疗前输出量的25%，与腮腺平均剂量的相关性最佳。当打算降低腮腺的平均剂量时，刺激流量测量是评估腮腺功能的最佳方法。
