Zinicola R, Pedrazzi G, Haboubi N, Nicholls R J
Department of Emergency Surgery, University Hospital Parma, Parma, Italy.
Department of Neuroscience, University of Parma, Parma, Italy.
Colorectal Dis. 2017 Jan;19(1):8-15. doi: 10.1111/codi.13565.
The T3 category of the TNM classification includes over 60% of all rectal tumours and encompasses the greatest variance in cancer-specific end-points than any other T category. The most recent edition of the cancer staging handbook of the American Joint Committee on Cancer (AJCC) dated 2010 does not divide T3 tumours into subgroups which reflect cancer-specific outcome more sensitively. The original aim of the present study was to review the literature to assess the influence of the degree of extramural extent of T3 rectal cancer on local recurrence and survival. An article written by the authors was accepted for publication but was withdrawn immediately after they became aware of the publication of the 4th edition of the TNM Supplement by the Union for International Cancer Control dated 2012, which was not accessible by the search system used. This article dealt with the subdivision of the T3 category although this was not included in the most up-to-date AJCC guidelines and was stated to be 'entirely optional'. Medline, PubMed and Cochrane Library searches were performed to identify all studies that investigated the degree of extramural spread and its relationship to survival and local recurrence. Twenty-two studies were identified of which 12 assessed the degree of histopathological extramural spread measured in millimetres. In 18 of the 22 studies the degree of extramural spread was a statistically significant prognostic factor for survival and local recurrence. Analysis of the studies indicated that the subdivision of category T3 rectal cancer into two subgroups of extramural spread ≤ 5 mm or more than 5 mm resulted in markedly different survival and local recurrence rates. The data were insufficient to allow validation of any greater subdivision. Measurement of the extent of extramural spread by MRI before any treatment agreed with the histopathological measurement in the surgical specimen to within 1 mm. The extent of extramural spread in T3 rectal cancer measured in millimetres is a powerful prognostic factor. A subdivision of T3 into T3a and T3b of less than or equal to or more than 5 mm appears to give the greatest discrimination of local recurrence and survival. Preoperative T3 subdivision by MRI has the same sensitivity as histopathological examination of the resected specimen. Given the clinical need for the pretreatment classification of the T3 category for oncological management planning, the evidence strongly indicates that the subdivision of the T3 category by MRI should be formally considered as part of the TNM staging system for rectal cancer.
TNM分类中的T3类别涵盖了超过60%的直肠肿瘤，并且在癌症特异性终点方面的差异比任何其他T类别都要大。美国癌症联合委员会（AJCC）2010年版癌症分期手册未将T3肿瘤细分为能更敏感反映癌症特异性结局的亚组。本研究的最初目的是回顾文献，评估T3期直肠癌壁外浸润程度对局部复发和生存的影响。作者撰写的一篇文章已被接受发表，但在他们得知国际癌症控制联盟2012年出版的第4版TNM增补版后立即撤回，该增补版无法通过所使用的检索系统获取。这篇文章涉及T3类别的细分，尽管这未包含在最新的AJCC指南中，且被声明为“完全可选择”。通过检索Medline、PubMed和Cochrane图书馆，以识别所有研究壁外扩散程度及其与生存和局部复发关系的研究。共识别出22项研究，其中12项评估了以毫米为单位测量的组织病理学壁外扩散程度。在这22项研究中的18项里，壁外扩散程度是生存和局部复发的统计学显著预后因素。对这些研究的分析表明，将T3期直肠癌细分为壁外扩散≤5毫米或＞5毫米的两个亚组，会导致生存和局部复发率明显不同。数据不足以对更细致的细分进行验证。在任何治疗前通过MRI测量的壁外扩散程度与手术标本中的组织病理学测量结果相差在1毫米以内。以毫米为单位测量的T3期直肠癌壁外扩散程度是一个有力的预后因素。将T3细分为T3a（≤5毫米）和T3b（＞5毫米）似乎对局部复发和生存具有最大的区分度。术前通过MRI对T3进行细分与对切除标本进行组织病理学检查具有相同的敏感性。鉴于肿瘤管理规划中对T3类别进行预处理分类的临床需求，有强有力的证据表明，通过MRI对T3类别进行细分应被正式视为直肠癌TNM分期系统的一部分。
