Withers H R, Peters L J, Taylor J M, Owen J B, Morrison W H, Schultheiss T E, Keane T, O'Sullivan B, van Dyk J, Gupta N
UCLA Radiation Oncology Center, USA.
Int J Radiat Oncol Biol Phys. 1995 Oct 15;33(3):563-8. doi: 10.1016/0360-3016(95)00229-R.
To evaluate the influence of dose fractionation and other factors on the development of late complications in mandibular bone, muscle, and mucosa of the oral cavity after external beam radiation therapy for carcinoma of the tonsil.
A retrospective analysis was made of the results in 676 patients treated with a spectrum of fractionation regimens in nine centers during the years 1976-1985. Only severe (Grades 3-4) late complications were analyzed.
With more than 5 years follow-up, it was found that total dose was a factor for all three types of complications, but that in other respects, the radiobiology of late-(> 3 months) developing mucosal ulcerations was different from that for mandibular necrosis and muscle injury. Dose per fraction was a significant factor for bone and muscle (estimated alpha/beta values of 0.85 Gy and 3.1 Gy, respectively). By contrast, mucosa showed no influence on response from change in fraction size over the range of approximately 1.0-3.5 Gy. Complications in bone and muscle were not related to overall treatment duration, whereas there was a significant inverse relationship for mucosa breakdown. The rate of development of complications was fastest in mucosa and slowest in bone. The appearance of complications by 4 years after treatment was about 80% of those developing by 8 years in the mucosa, 66% in muscle, and about 50% in bone. The high alpha/beta ratio, inverse relationship with overall treatment duration, and faster development of mucosal complications suggests that they may develop as a consequence of earlier mucosal injury. As anticipated, adequate retrospective analysis of acute complications could not be made even when objective criteria such as weight loss, unplanned delays in completing treatment, or hospitalization during treatment were the measures. Field size was a significant factor for mandible complications, but not for muscle or mucosa.
The radiobiological characteristics of bone and muscle were those characteristic of other late-responding tissues, whereas late sequelae in mucosa had radiobiological parameters similar to those for acute responses. Field size was a significant factor for bone complications but not for others.
评估剂量分割及其他因素对扁桃体癌外照射放疗后下颌骨、肌肉及口腔黏膜晚期并发症发生情况的影响。
对1976年至1985年间九个中心采用一系列分割方案治疗的676例患者的结果进行回顾性分析。仅分析严重（3 - 4级）晚期并发症。
经过5年以上随访，发现总剂量是所有三种并发症类型的一个因素，但在其他方面，晚期（> 3个月）发生的黏膜溃疡的放射生物学与下颌骨坏死和肌肉损伤不同。每次分割剂量对骨骼和肌肉是一个重要因素（估计α/β值分别为0.85 Gy和3.1 Gy）。相比之下，在大约1.0 - 3.5 Gy范围内，黏膜对分割大小变化的反应没有影响。骨骼和肌肉的并发症与总治疗时间无关，而黏膜破溃则存在显著的负相关关系。并发症的发生速度在黏膜中最快，在骨骼中最慢。治疗后4年出现的并发症约为黏膜8年时的80%，肌肉的66%，骨骼的约50%。高α/β比值、与总治疗时间的负相关关系以及黏膜并发症的更快发展表明，它们可能是早期黏膜损伤的结果。正如预期的那样，即使采用体重减轻、治疗完成的计划外延迟或治疗期间住院等客观标准作为衡量指标，也无法对急性并发症进行充分的回顾性分析。照射野大小是下颌骨并发症的一个重要因素，但对肌肉或黏膜不是。
骨骼和肌肉的放射生物学特征是其他晚反应组织的特征，而黏膜晚期后遗症的放射生物学参数与急性反应相似。照射野大小是骨骼并发症的一个重要因素，但对其他组织不是。
