Department of Thoracic Surgery, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China.
Ann Surg Oncol. 2010 Jul;17(7):1901-11. doi: 10.1245/s10434-010-0948-9. Epub 2010 Feb 10.
The current American Joint Committee on Cancer (AJCC) staging system for esophageal cancer does not define the minimum number of lymph nodes (LNs) necessary for accurate nodal staging. This study aimed to seek the minimum number of LNs examined for adequate nodal staging of patients with node-negative esophageal cancer.
We conducted a retrospective review of 592 patients undergoing R0 resection with node-negative esophageal carcinoma between December 1996 and December 2004. The relationship between the total number of examined LNs and death from esophageal cancer was investigated by means of a scatterplot of this variable versus Martingale residuals from a Cox proportional hazard regression model without the variable of interest. A smoothed line fit of the scatterplot was applied to detect the reasonable cutoff point.
The patients were classified into four categories according to the number of examined LNs: < or =5, 6 to 9, 10 to 17, and > or =18. A reduced hazard ratio of death was observed with an increasing number of LNs examined. The 5-year cancer-specific survival rate was 42.8% among patients with < or =5 LNs examined, compared with 52.6, 56.8, and 75% for those with 6-9 LNs, 10-17 LNs, and > or =18 LNs, respectively. Multivariate Cox regression analysis suggested that female sex, lower grade of cell differentiation, lower T category and increasing number of examined LNs were independent factors favoring cancer-specific survival.
At least 18 LNs should be resected for accurate staging of operable esophageal carcinoma. However, a validation from other institute is warranted.
目前的美国癌症联合委员会（AJCC）食管癌分期系统并未定义准确淋巴结分期所需的最小淋巴结数量（LNs）。本研究旨在寻找阴性淋巴结食管癌患者淋巴结分期的最小LN 检查数量。
我们回顾性分析了 1996 年 12 月至 2004 年 12 月期间接受 R0 切除且无淋巴结阴性食管癌的 592 例患者。通过将该变量与不包含感兴趣变量的 Cox 比例风险回归模型中的 Martingale 残差的散点图进行比较，研究了总检查 LNs 数量与食管癌死亡之间的关系。应用散点图的平滑线拟合来检测合理的截断点。
根据检查的 LNs 数量，患者分为四组：< =5、6-9、10-17 和>=18。随着检查的 LNs 数量增加，死亡的危险比降低。检查的 LNs< =5 的患者 5 年癌症特异性生存率为 42.8%，而检查的 LNs 为 6-9、10-17 和>=18 的患者分别为 52.6%、56.8%和 75%。多变量 Cox 回归分析表明，女性、较低的细胞分化程度、较低的 T 分期和增加的检查 LNs 数量是有利于癌症特异性生存的独立因素。
至少应切除 18 个 LNs 以准确分期可切除性食管癌。然而，需要其他机构的验证。
