Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
Baylor College of Medicine, Houston, Texas.
Cancer. 2019 May 1;125(9):1536-1546. doi: 10.1002/cncr.31944. Epub 2019 Jan 8.
The objective of the current study was to characterize the incidence, pattern, and impact on oncologic outcomes of retropharyngeal lymph node (RPLN) involvement in HPV-associated oropharyngeal cancer (OPC).
Data regarding patients with HPV-associated OPC who were treated at The University of Texas MD Anderson Cancer Center with intensity-modulated radiotherapy from 2004 through 2013 were analyzed retrospectively. RPLN status was determined by reviewing pretreatment imaging and/or reports. Outcomes analysis was restricted to patients with lymph node-positive (+) disease. Kaplan-Meier survival estimates were generated and survival curves were compared using the log-rank test. Bayesian information criterion assessed model performance changes with the addition of RPLN status to current American Joint Committee on Cancer staging. Competing risk analysis compared modes of disease recurrence.
The incidence of radiographic RPLN involvement was 9% (73 of 796 patients) and was found to vary by primary tumor site. The 5-year rates of freedom from distant metastases (FDM) and overall survival were lower in patients with RPLN(+) status compared with those with RPLN-negative (-) status (84% vs 93% [P = .0327] and 74% vs 87% [P = .0078], respectively). RPLN(+) status was not found to be associated with outcomes on multivariate analysis. Bayesian information criterion analysis demonstrated that current American Joint Committee on Cancer staging was not improved with the inclusion of RPLN. Locoregional and distant disease recurrence probabilities for those patients with RPLN(+) status were 8% and 13%, respectively, compared with 10% and 6%, respectively, for those with RPLN(-) status. RPLN(+) status portended worse 5-year FDM in the low-risk subgroup (smoking history of <10 pack-years) and among patients who received concurrent chemotherapy but not induction chemotherapy.
RPLN(+) status was associated with worse overall survival and FDM on univariate but not multivariate analysis. In subgroup analyses, RPLN(+) status was associated with poorer FDM in both patients with a smoking history of <10 pack-years and those who received concurrent chemotherapy, suggesting that RPLN(+) status could be considered an exclusion criteria in treatment deintensification efforts seeking to omit chemotherapy.
本研究旨在描述 HPV 相关口咽癌（OPC）患者后咽淋巴结（RPLN）受累的发生率、模式及其对肿瘤学结局的影响。
回顾性分析了 2004 年至 2013 年在德克萨斯大学 MD 安德森癌症中心接受调强放疗治疗的 HPV 相关 OPC 患者的数据。通过回顾术前影像学和/或报告确定 RPLN 状态。结果分析仅限于淋巴结阳性（+）疾病的患者。使用对数秩检验生成 Kaplan-Meier 生存估计，并比较生存曲线。贝叶斯信息准则评估了将 RPLN 状态添加到当前美国癌症联合委员会分期后模型性能的变化。竞争风险分析比较了疾病复发的模式。
影像学 RPLN 受累的发生率为 9%（796 例患者中有 73 例），且与原发肿瘤部位有关。与 RPLN（-）状态相比，RPLN（+）状态患者的无远处转移（FDM）和总生存率较低（84% vs 93%[P=0.0327]和 74% vs 87%[P=0.0078]）。多变量分析显示 RPLN（+）状态与结局无关。贝叶斯信息准则分析表明，当前的美国癌症联合委员会分期在纳入 RPLN 后并未得到改善。与 RPLN（-）状态患者的局部和远处疾病复发率分别为 10%和 6%相比，RPLN（+）状态患者的局部和远处疾病复发率分别为 8%和 13%。对于吸烟史<10 包年的低危亚组和接受同期化疗但未接受诱导化疗的患者，RPLN（+）状态预示着 5 年 FDM 更差。
RPLN（+）状态与单因素而非多因素分析的总体生存和 FDM 较差相关。在亚组分析中，在吸烟史<10 包年的患者和接受同期化疗的患者中，RPLN（+）状态与较差的 FDM 相关，这表明 RPLN（+）状态可能被认为是省略化疗的治疗减毒努力的排除标准。
