*Department of Surgery, University of California, Davis, CA, USA.
Ann Surg. 2011 Jan;253(1):82-7. doi: 10.1097/SLA.0b013e3181ffa780.
The presence and number of nodal metastasis significantly impact colon cancer prognosis. Similarly, the number of resected/evaluated nodes impacts staging accuracy. This ratio of metastatic to examined nodes or lymph node ratio (LNR) may have independent prognostic value in colon carcinoma.
: To evaluate the impact of LNR on overall survival in colon cancer patients with fewer than 12 or 12 examined nodes or more.
Patients (n = 36,712) with node-positive nonmetastatic colon cancer diagnosed between 1992 and 2004 were identified from the Surveillance, Epidemiology, and End Results database and stratified according to LNR and number of nodes examined. Survival was estimated by Kaplan-Meier method, and differences analyzed by log-rank test. A Cox proportional hazards model was used for multivariate analysis.
Patients with fewer than 12 nodes were older and male and had lower primary tumor stage, grade, and N stage (P < 0.01). Survival appeared greater with 12 total nodes examined or more (median 53 vs. 66 months, P < 0.001). Within each LNR stratum, survival with 12 nodes or more was improved for those with less than 10% of nodes positive for cancer, but was worse with higher LNRs (P < 0.01). Lymph node ratio was significantly associated with survival independent of total nodes (HR 1.24-5.12, P < 0.001). Other significant factors included age, race, tumor grade, stage, location, and N stage.
Metastatic LNR independently estimates survival in Stage III colon cancer, irrespective of number of nodes examined. However, statistically significant differences in each LNR stratum between those with resection of fewer than 12 or 12 nodes or more would indicate that a 12-node minimum may still be necessary for accurate staging.
淋巴结转移的存在和数量对结肠癌的预后有重要影响。同样，切除/评估的淋巴结数量也会影响分期的准确性。淋巴结转移与检查淋巴结的比例或淋巴结比率（LNR）在结肠癌中可能具有独立的预后价值。
评估 LNR 对淋巴结阳性非转移性结肠癌患者中淋巴结转移数量较少（<12 个或 12 个）或较多（≥12 个）的总体生存的影响。
从监测、流行病学和最终结果数据库中确定了 1992 年至 2004 年期间诊断为淋巴结阳性非转移性结肠癌的患者（n=36712），并根据 LNR 和检查的淋巴结数量进行分层。通过 Kaplan-Meier 法估计生存情况，通过对数秩检验分析差异。采用 Cox 比例风险模型进行多因素分析。
淋巴结转移数量<12 个的患者年龄较大，男性比例较高，原发肿瘤分期、分级和 N 分期较低（P<0.01）。检查 12 个或更多淋巴结的患者的生存时间更长（中位数 53 个月与 66 个月，P<0.001）。在每个 LNR 分层内，LNR<10%的患者检查 12 个或更多淋巴结时生存情况得到改善，但 LNR 较高的患者生存情况更差（P<0.01）。LNR 与总淋巴结数独立相关（HR 1.24-5.12，P<0.001）。其他重要因素包括年龄、种族、肿瘤分级、分期、位置和 N 分期。
转移性 LNR 独立于检查的淋巴结数量，估计 III 期结肠癌的生存情况。然而，在 LNR 各分层中，那些切除<12 个或 12 个淋巴结或更多的患者之间存在统计学显著差异，这表明为了准确分期，仍可能需要 12 个淋巴结的最低数量。
