Department of Breast Surgery, Cancer Center and Cancer Institute, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
Mayo Clin Proc. 2012 Dec;87(12):1171-80. doi: 10.1016/j.mayocp.2012.07.023.
To examine the relationship between large tumor size and breast cancer-specific mortality (BCSM), especially in a subset of patients with negative lymph nodes (LNs).
We used the Surveillance, Epidemiology and End Results registry to identify 107,705 female patients diagnosed from January 1, 1990, through December 31, 2003, as having invasive breast cancer and treated with surgery and LN dissection. Relevant issues unclear in the database were studied in an additional 335 patients with locally advanced disease treated with neoadjuvant chemotherapy.
In the multivariable analysis, a significant interaction was found between tumor size and LN involvement (P<.001). In LN-negative diseases, the relationship between tumor size and BCSM was piecewise. Using 21- to 30-mm tumors as the reference, the hazard ratio (HR) of BCSM increased with increasing tumor size until a peak at 41 to 50 mm (HR, 1.49; P<.001), after which increasing tumor size was unexpectedly related to decreasing hazard, with a nadir at 61 to 80 mm (HR, 1.06; P=.70). The 61- to 80-mm tumors exhibited a significantly lower BCSM compared with the 41- to 50-mm (P=.02) and greater than 80-mm (P=.03) subgroups. This pattern remained after stratification by estrogen receptor status but was not observed in patients with LN-positive disease. Further analysis indicated that the survival advantage of 61- to 80-mm tumors in LN-negative disease might result from its low risk of distant metastasis.
A relatively larger tumor size without LN involvement may be a surrogate for biologically indolent disease of distant metastasis. Our findings, if validated in other large databases, may provide better understanding of breast cancer biology.
研究大肿瘤尺寸与乳腺癌特异性死亡率（BCSM）之间的关系，特别是在淋巴结（LNs）阴性的患者亚组中。
我们使用监测、流行病学和最终结果（SEER）登记处，确定了 1990 年 1 月 1 日至 2003 年 12 月 31 日期间接受手术和 LNs 解剖治疗的 107705 名患有浸润性乳腺癌的女性患者。在数据库中不明确的相关问题，在另外 335 名接受新辅助化疗的局部晚期疾病患者中进行了研究。
在多变量分析中，发现肿瘤大小和 LNs 受累之间存在显著的相互作用（P<.001）。在 LNs 阴性疾病中，肿瘤大小与 BCSM 之间的关系是分段的。使用 21-30mm 的肿瘤作为参考，BCSM 的风险比（HR）随着肿瘤尺寸的增加而增加，直到 41-50mm 时达到峰值（HR，1.49；P<.001），之后肿瘤尺寸的增加出乎意料地与风险降低相关，在 61-80mm 时达到最低点（HR，1.06；P=.70）。61-80mm 的肿瘤与 41-50mm（P=.02）和大于 80mm（P=.03）亚组相比，BCSM 显著降低。这种模式在雌激素受体状态分层后仍然存在，但在 LNs 阳性疾病患者中未观察到。进一步分析表明，LN 阴性疾病中 61-80mm 肿瘤的生存优势可能是由于其远处转移的低风险。
没有 LNs 受累的相对较大肿瘤尺寸可能是远处转移生物学惰性疾病的替代指标。如果在其他大型数据库中得到验证，我们的发现可能会更好地理解乳腺癌生物学。
