结外延伸(ENE)是癌症从淋巴结(LN)向外生长到周围组织的一种模式。通过肿瘤通过LN囊的整个厚度的破坏和渗透来严格定义。在包括头颈部鳞状细胞癌(HNSCC)的各种恶性肿瘤中,ENE的存在通常与侵袭性癌症表型相关。在HNSCC,ENE与远处转移风险增加和局部控制率降低相关。在第八版美国癌症联合委员会(AJCC)和国际癌症控制联盟(UICC)TNM分类中,在组织病理学上检测到的ENE(病理性ENE;PENE)现已作为人乳头瘤病毒(HPV)阴性HNSCC的风险分层因子。虽然ENE在近一个世纪前首次被描述,几个问题仍未解决,包括在定义上缺乏共识,术语,以及在放射成像中检测到的PENE和ENE的广泛接受的评估标准和分级系统(成像检测的ENE;IENE)。此外,关于IENE和PENE的预后意义的数据相互矛盾,特别是在HPV相关的HNSCC的背景下。在这里,我们回顾了有关HNSCC中ENE的现有文献,强调有争议的领域,并确定需要协同研究努力的关键差距。
Extranodal extension (ENE) is a pattern of cancer growth from within the lymph node (LN) outward into perinodal tissues, critically defined by disruption and penetration of the tumor through the entire thickness of the LN capsule. The presence of ENE is often associated with an aggressive cancer phenotype in various malignancies including head and neck squamous cell carcinoma (HNSCC). In HNSCC, ENE is associated with increased risk of distant metastasis and lower rates of locoregional control. ENE detected on histopathology (pathologic ENE; pENE) is now incorporated as a risk-stratification factor in human papillomavirus (HPV)-negative HNSCC in the eighth edition of the American Joint Committee on Cancer (AJCC) and the Union for International Cancer Control (UICC) TNM classification. Although ENE was first described almost a century ago, several issues remain unresolved, including lack of consensus on definitions, terminology, and widely accepted assessment criteria and grading systems for both pENE and ENE detected on radiological imaging (imaging-detected ENE; iENE). Moreover, there is conflicting data on the prognostic significance of iENE and pENE, particularly in the context of HPV-associated HNSCC. Herein, we
review the existing literature on ENE in HNSCC, highlighting areas of controversy and identifying critical gaps requiring concerted research efforts.