Saito Tetsuo, Toya Ryo, Tomitaka Etsushi, Matsuyama Tomohiko, Ninomura Satoshi, Watakabe Takahiro, Oya Natsuo
Department of Radiation Oncology, Kumamoto University Hospital, Kumamoto, Japan.
Department of Radiation Oncology, Hitoyoshi Medical Center, Hitoyoshi, Japan.
Adv Radiat Oncol. 2018 Aug 23;4(1):118-126. doi: 10.1016/j.adro.2018.08.006. eCollection 2019 Jan-Mar.
Even when index pain (pain caused by the irradiated tumor) is palliated after radiation therapy (RT), patients may not derive the full benefits of RT in the presence of another, more intense pain. In this case-control study with prospectively collected data, we sought to identify predictors of the predominance of nonindex pain after palliative RT.
Brief Pain Inventory data were collected from patients who received RT for painful tumors. The treating radiation oncologists prospectively evaluated the intensity and origin of nonindex pain. Patients were diagnosed with predominance of other pain (POP) if nonindex pain of malignant or unknown origin was present and had a greater worst pain score than the index pain at the 1- or 2-month follow-up. Changes in pain interference from baseline to follow-up were compared between the 2 groups using Mann-Whitney tests. Using variables that were identified as significant in a multivariable logistic regression analysis, we developed a prediction model for POP.
Of the 170 patients who were evaluable at the 2-month follow-up, 24 (14%) were diagnosed with POP. At the 2-month follow-up examination of the patients with POP, none of the items of the pain interference scores were reduced from baseline; in contrast, patients without POP experienced significant reductions in all items. Multivariable analysis using the backward elimination method indicated that age ≤65 years, the presence of nonindex pain of malignant or unknown origin at baseline, and no opioid analgesic use at baseline were significant independent predictors of POP. As the number of the risk factors increased, the proportion of patients with POP increased.
We identified three predictors of POP. For patients likely to have POP, careful follow-up is important, and new palliative RT or analgesics should be used when needed.
即使在放射治疗（RT）后，肿瘤照射引起的初始疼痛得到缓解，但如果存在另一种更强烈的疼痛，患者可能无法充分受益于RT。在这项前瞻性收集数据的病例对照研究中，我们试图确定姑息性RT后非初始疼痛占主导地位的预测因素。
从接受RT治疗疼痛性肿瘤的患者中收集简明疼痛量表数据。主治放射肿瘤学家前瞻性评估非初始疼痛的强度和来源。如果在1个月或2个月随访时存在恶性或不明来源的非初始疼痛，且其最严重疼痛评分高于初始疼痛，则患者被诊断为其他疼痛占主导（POP）。使用Mann-Whitney检验比较两组从基线到随访时疼痛干扰的变化。利用多变量逻辑回归分析中确定为显著的变量，我们建立了一个POP预测模型。
在2个月随访时可评估的170例患者中，24例（14%）被诊断为POP。在对POP患者进行的2个月随访检查中，疼痛干扰评分的所有项目均未从基线降低；相比之下，无POP的患者所有项目均有显著降低。采用向后排除法的多变量分析表明，年龄≤65岁、基线时存在恶性或不明来源的非初始疼痛以及基线时未使用阿片类镇痛药是POP的显著独立预测因素。随着危险因素数量的增加，POP患者的比例增加。
我们确定了POP的三个预测因素。对于可能患有POP的患者，仔细随访很重要，必要时应使用新的姑息性RT或镇痛药。
