J Am Dent Assoc. 2018 Jun;149(6):432-441. doi: 10.1016/j.adaj.2018.01.031. Epub 2018 Apr 11.
Conventional 3-dimensional conformal radiation therapy (3DCRT) for head and neck cancer (HNC) can cause hyposalivation, leading to caries and tooth extraction-related osteoradionecrosis. Intensity-modulated radiation therapy (IMRT) delivers more focused radiation than does 3DCRT. To reduce hyposalivation, the Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) guidelines limit salivary gland radiation dose. In this study, the authors compared the salivary flow rate in patients receiving 3DCRT and those receiving IMRT and evaluated the effect of their treatment satisfying the QUANTEC guidelines on hyposalivation.
The authors evaluated findings in 96 patients with HNC who received radiation therapy (RT); 20 received unilateral 3DCRT, 17 received bilateral 3DCRT, and 59 received IMRT. The authors measured stimulated whole saliva before radiation and 3 and 12 months after radiation. The authors defined hyposalivation as stimulated whole saliva less than 3.5 grams per 5 minutes.
At 12 months, 50% and 54% of patients receiving unilateral 3DCRT and IMRT, respectively, exhibited nonstatistically significant hyposalivation compared with 71% of patients receiving bilateral 3DCRT (P = .2). A lower proportion of patients receiving IMRT (27%) and unilateral 3DCRT (5%) had decreased salivary flow (< 25% of baseline) than did those receiving bilateral 3DCRT (59%; P < .004); fewer patients whose treatment satisfied the QUANTEC guidelines exhibited hyposalivation than patients whose treatment did not fullfill QUANTEC guidelines (39% versus 71%; P < .002).
Twelve months after RT for HNC, treatment satisfying the QUANTEC guidelines resulted in decreased hyposalivation. Unilateral 3DCRT and IMRT may result in less hyposalivation than does bilateral 3DCRT.
Patients with HNC treated with modern RT techniques have a lower risk of developing hyposalivation, particularly if the QUANTEC guidelines are met, which also may result in decreased dental caries, tooth extractions, and postextraction osteoradionecrosis. Management of HNC requires a multidisciplinary team, including dentists and radiation oncologists.
头颈部癌症（HNC）的常规三维适形放疗（3DCRT）可导致唾液减少，从而导致龋齿和与拔牙相关的放射性骨坏死。调强放疗（IMRT）比 3DCRT 提供更集中的辐射。为了减少唾液减少，正常组织效应定量分析临床（QUANTEC）指南限制了唾液腺的辐射剂量。在这项研究中，作者比较了接受 3DCRT 和 IMRT 治疗的患者的唾液流量，并评估了满足 QUANTEC 指南的治疗对唾液减少的影响。
作者评估了 96 例接受放疗（RT）的 HNC 患者的发现；20 例接受单侧 3DCRT，17 例接受双侧 3DCRT，59 例接受 IMRT。作者在放疗前和放疗后 3 个月和 12 个月测量了刺激全唾液。作者将唾液减少定义为刺激全唾液每 5 分钟少于 3.5 克。
在 12 个月时，分别接受单侧 3DCRT 和 IMRT 的患者中有 50%和 54%出现非统计学显著的唾液减少，而接受双侧 3DCRT 的患者中有 71%（P =.2）。接受 IMRT（27%）和单侧 3DCRT（5%）的患者中，唾液流量下降（<基线的 25%）的比例低于接受双侧 3DCRT 的患者（59%；P <.004）；满足 QUANTEC 指南的治疗的患者中出现唾液减少的比例低于未满足 QUANTEC 指南的治疗的患者（39%比 71%；P <.002）。
HNC 放疗后 12 个月，满足 QUANTEC 指南的治疗导致唾液减少减少。单侧 3DCRT 和 IMRT 可能导致唾液减少少于双侧 3DCRT。
接受现代 RT 技术治疗的 HNC 患者唾液减少的风险较低，特别是如果满足 QUANTEC 指南，这也可能导致龋齿、拔牙和拔牙后放射性骨坏死减少。HNC 的管理需要一个多学科团队，包括牙医和放射肿瘤学家。
