Abstract：
BACKGROUND: An estimated 20% of patients with oral and oropharyngeal squamous cell carcinoma (OOSCC) have micrometastases (Mi) or isolated tumor cells (ITC) in the cervical lymph nodes that evade detection by standard histological evaluation of lymph node sections. Lymph node Mi and ITC could be one reason for regional recurrence after neck dissection. The aim of this study was to review the existing data regarding the impact of Mi on the survival of patients with OOSCC.
METHODS: PubMed and the Cochrane Library were searched for articles reporting the impact of Mi and ITC on patient survival. Two authors independently assessed the methodological quality of retrieved studies using the Downs and Black index. Data were also extracted on study type, number of included patients, mode of histological analysis, statistical analysis, and prognostic impact.
RESULTS: Sixteen articles with a total of 2064 patients were included in the review. Among the 16 included studies, eight revealed a statistically significant impact of Mi on at least one endpoint in the Kaplan-Meier and/or multivariate analysis. Three studies regarded Mi as Ma, while five studies found no impact of Mi on survival. Only one study demonstrated an impact of ITC on patient\'s prognosis in the univariate but not in the multivariate analysis.
CONCLUSIONS: The majority of cases included in the review were patients with oral cancer. The findings provide low-certainty evidence that Mi negatively impacts survival. Data on ITC were scarcer, so no conclusions can be drawn about their effect on survival. The lower threshold to discriminate between Mi and ITC should be defined for OOSCC since the existing thresholds are based on data from different tumors. The histological, immunohistological, and anatomical characteristics of Mi and ITC in OOSCC as well as the effect of radiotherapy on Mi should be further investigated separately for oral and oropharyngeal carcinomas.
METHODS: PubMed and the Cochrane Library were searched for articles reporting the impact of Mi and ITC on patient survival. Two authors independently assessed the methodological quality of retrieved studies using the Downs and Black index. Data were also extracted on study type, number of included patients, mode of histological analysis, statistical analysis, and prognostic impact.
RESULTS: Sixteen articles with a total of 2064 patients were included in the review. Among the 16 included studies, eight revealed a statistically significant impact of Mi on at least one endpoint in the Kaplan-Meier and/or multivariate analysis. Three studies regarded Mi as Ma, while five studies found no impact of Mi on survival. Only one study demonstrated an impact of ITC on patient\'s prognosis in the univariate but not in the multivariate analysis.
CONCLUSIONS: The majority of cases included in the review were patients with oral cancer. The findings provide low-certainty evidence that Mi negatively impacts survival. Data on ITC were scarcer, so no conclusions can be drawn about their effect on survival. The lower threshold to discriminate between Mi and ITC should be defined for OOSCC since the existing thresholds are based on data from different tumors. The histological, immunohistological, and anatomical characteristics of Mi and ITC in OOSCC as well as the effect of radiotherapy on Mi should be further investigated separately for oral and oropharyngeal carcinomas.
摘要：
背景：估计有20％的口腔和口咽鳞状细胞癌（OOSCC）患者在颈淋巴结中存在微转移（Mi）或孤立的肿瘤细胞（ITC），这些肿瘤细胞无法通过标准的淋巴结组织学评估进行检测。淋巴结Mi和ITC可能是颈淋巴结清扫术后局部复发的原因之一。这项研究的目的是回顾有关Mi对OOSCC患者生存影响的现有数据。
方法：在PubMed和Cochrane图书馆中检索报道Mi和ITC对患者生存影响的文章。两位作者使用Downs和Black指数独立评估了检索到的研究的方法学质量。还提取了研究类型的数据，纳入患者的数量，组织学分析的模式，统计分析,和预后影响。
结果：共纳入16篇文献，共2064例患者。在纳入的16项研究中，8在Kaplan-Meier和/或多变量分析中揭示了Mi对至少一个终点的统计学显著影响。三项研究将Mi视为Ma，而五项研究发现Mi对生存率没有影响。只有一项研究证明了ITC对患者预后的影响，但在多变量分析中没有。
结论：纳入本综述的大多数病例为口腔癌患者。这些发现提供了低确定性的证据，表明Mi对生存产生了负面影响。ITC的数据很少，因此无法得出关于它们对生存的影响的结论。应针对OOSCC定义区分Mi和ITC的下限阈值,因为现有阈值是基于来自不同肿瘤的数据。组织学，免疫组织学，OOSCC中Mi和ITC的解剖特征以及放疗对Mi的影响应分别针对口腔癌和口咽癌进行进一步研究。
方法：在PubMed和Cochrane图书馆中检索报道Mi和ITC对患者生存影响的文章。两位作者使用Downs和Black指数独立评估了检索到的研究的方法学质量。还提取了研究类型的数据，纳入患者的数量，组织学分析的模式，统计分析,和预后影响。
结果：共纳入16篇文献，共2064例患者。在纳入的16项研究中，8在Kaplan-Meier和/或多变量分析中揭示了Mi对至少一个终点的统计学显著影响。三项研究将Mi视为Ma，而五项研究发现Mi对生存率没有影响。只有一项研究证明了ITC对患者预后的影响，但在多变量分析中没有。
结论：纳入本综述的大多数病例为口腔癌患者。这些发现提供了低确定性的证据，表明Mi对生存产生了负面影响。ITC的数据很少，因此无法得出关于它们对生存的影响的结论。应针对OOSCC定义区分Mi和ITC的下限阈值,因为现有阈值是基于来自不同肿瘤的数据。组织学，免疫组织学，OOSCC中Mi和ITC的解剖特征以及放疗对Mi的影响应分别针对口腔癌和口咽癌进行进一步研究。
