Division of Breast Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
Comprehensive Breast Health Center, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
Breast Cancer Res Treat. 2023 Oct;201(3):547-560. doi: 10.1007/s10549-023-07044-5. Epub 2023 Jul 20.
Invasive lobular cancer (ILC) is the second most common histology type of breast cancer followed by invasive ductal carcinoma (IDC). This study aimed to investigate the characteristic, treatment strategies, and clinical outcomes of ILC based on a national population-based cancer registry.
This study recruited 2671 ILC and 52,215 IDC patients diagnosed between 2011 and 2017 using the Taiwan Cancer Registry (TCR). Correlations between ILC and IDC subgroups were assessed using 1:4 propensity score matching and compared using the χ2 test. Disease free survival(DFS) and overall survival(OS) were estimated using the Kaplan-Meier method with the log-rank test. The risk of disease relapse and mortality were assessed using Cox proportional hazards model.
ILC patients had larger tumor sizes, more positive axillary lymph node involvement, lower tumor grade, and higher cancer stage than IDC patients. After matching, ILC patients had a significantly higher rate of receiving mastectomy (58.93% and 53.85%) and positive surgical margin regardless of surgery type. ILC exhibited a significantly higher rate of distant metastasis than IDC(3.67% and 2.93%), but no difference in local recurrence rate, DFS or OS between the two groups. Higher cancer stage, higher grade, and mastectomy were risk factors for disease relapse and cancer-specific mortality. The hormone receptor-positive and HER2 over-expression subtypes were found to be associated with a reduced risk of disease relapse, while only PR positivity was associated with a decreased risk of mortality. (all P-values < 0.05).
ILC patients had a higher mastectomy rate, higher surgical margin rate and distant metastasis rate than IDC patients. There is no significant difference in DFS or OS between ILC and IDC patients. Mastectomy was associated with poor outcomes regardless of ILC or IDC.
浸润性小叶癌（ILC）是继浸润性导管癌（IDC）之后第二常见的乳腺癌组织学类型。本研究旨在基于全国人群癌症登记处调查 ILC 的特征、治疗策略和临床结局。
本研究使用台湾癌症登记处（TCR）招募了 2671 例 ILC 和 52215 例 IDC 患者，这些患者分别于 2011 年至 2017 年被诊断为 ILC 和 IDC。使用 1:4 倾向评分匹配评估 ILC 和 IDC 亚组之间的相关性，并使用 χ2 检验进行比较。使用 Kaplan-Meier 方法和对数秩检验估计无病生存（DFS）和总生存（OS）。使用 Cox 比例风险模型评估疾病复发和死亡的风险。
与 IDC 患者相比，ILC 患者的肿瘤更大，腋窝淋巴结阳性受累更多，肿瘤分级更低，癌症分期更高。匹配后，无论手术类型如何，ILC 患者接受乳房切除术（58.93%和 53.85%）和阳性切缘的比例明显更高。与 IDC 相比，ILC 远处转移的发生率明显更高（3.67%和 2.93%），但两组局部复发率、DFS 或 OS 无差异。更高的癌症分期、更高的分级和乳房切除术是疾病复发和癌症特异性死亡的危险因素。激素受体阳性和 HER2 过表达亚型与降低疾病复发风险相关，而仅 PR 阳性与降低死亡风险相关。（所有 P 值均<0.05）。
与 IDC 患者相比，ILC 患者的乳房切除术率、切缘阳性率和远处转移率更高。ILC 和 IDC 患者的 DFS 或 OS 无显著差异。无论 ILC 或 IDC 患者，乳房切除术均与不良结局相关。
