Arnold Alexander, Kloor Matthias, Jansen Lina, Chang-Claude Jenny, Brenner Hermann, von Winterfeld Moritz, Hoffmeister Michael, Bläker Hendrik
Institute of Pathology, Charité University Medicine, Virchoweg 15 / Charitéplatz 1, 10117, Berlin, Germany.
Institute of Pathology, University of Heidelberg, Heidelberg, Germany.
Virchows Arch. 2017 Jul;471(1):57-64. doi: 10.1007/s00428-017-2150-y. Epub 2017 May 23.
The number of lymph nodes retrieved from colorectal cancer (CRC) resection specimens is crucial for adequate diagnosis and therapy. Previous studies indicate that in addition to the extent of surgical resection and the quality of pathological lymph node examination, non-modifiable tumour parameters like microsatellite instability (MSI) are associated with higher lymph node count. In order to study the potential influence of MSI on lymph node count, we analysed a previously MSI-typed population of CRC patients (n = 1196) to determine the relationship between MSI and the frequency with which at least 12 lymph nodes were retrieved, as well as the mean and median number of retrieved lymph nodes. MSI was associated with an increased frequency of 12-node retrieval, as well as a higher mean and median lymph node count in the overall analysis (p 0.004 and 0.001 for 12-node retrieval and lymph node count, respectively). However, when the analysis was restricted to cancers of the proximal colon, the main location of microsatellite unstable tumours (84% in our study), no association between MSI and 12-node retrieval was found. Subcategorisation by UICC stage of proximally located cancers showed a statistically significant increase in the lymph node count only in microsatellite unstable stage I tumours (p 0.010). In conclusion, our data shows that previously reported associations between MSI and higher lymph node count are mainly a consequence of the increased incidence of microsatellite unstable cancer in the proximal colon. Our finding that MSI is related to a significantly higher mean lymph node count in proximal stage I cancers may indicate that the immunogenicity of this molecular tumour type induces earlier lymph node activation.
从结直肠癌（CRC）切除标本中获取的淋巴结数量对于充分的诊断和治疗至关重要。先前的研究表明，除了手术切除范围和病理淋巴结检查质量外，微卫星不稳定性（MSI）等不可改变的肿瘤参数与更高的淋巴结数量相关。为了研究MSI对淋巴结数量的潜在影响，我们分析了先前已进行MSI分型的CRC患者群体（n = 1196），以确定MSI与至少获取12个淋巴结的频率以及获取淋巴结的平均数和中位数之间的关系。在总体分析中，MSI与12个淋巴结获取频率增加以及更高的平均和中位数淋巴结数量相关（12个淋巴结获取和淋巴结数量的p值分别为0.004和0.001）。然而，当分析仅限于近端结肠癌（微卫星不稳定肿瘤的主要部位，在我们的研究中占84%）时，未发现MSI与12个淋巴结获取之间存在关联。按UICC分期对近端癌症进行亚分类显示，仅在微卫星不稳定的I期肿瘤中淋巴结数量有统计学显著增加（p = 0.010）。总之，我们的数据表明，先前报道的MSI与更高淋巴结数量之间的关联主要是近端结肠中微卫星不稳定癌症发病率增加的结果。我们发现MSI与近端I期癌症中显著更高的平均淋巴结数量相关，这可能表明这种分子肿瘤类型的免疫原性诱导了更早的淋巴结激活。
