Cleveland Clinic Foundation, Cleveland, OH, USA.
Breast Cancer Res Treat. 2017 Oct;165(3):499-504. doi: 10.1007/s10549-017-4367-5. Epub 2017 Jul 8.
Metaplastic breast cancer (MBC) is a rare, aggressive variant of breast cancer, with limited data available regarding treatment and outcomes. This study aims to review patients with MBC treated at our tertiary care institution with an emphasis on the role of treatment modality and histologic classification.
With IRB-approval, we queried our pathology database for patients with MBC diagnosis. All cases were re-evaluated by dedicated breast pathologists and confirmed as MBC breast cancer. Patient demographics, clinical/pathologic histology, and treatment were analyzed with respect to outcomes including local-regional recurrence (LRR), distant metastasis (DM), and overall survival (OS). Univariate and multivariate Cox proportional hazards models were performed to evaluate the impact on outcomes. Kaplan-Meier methods estimated survival.
We evaluated 113 patients with MBC diagnosed between 2002 and 2013. Median age was 61 years and median pathologic tumor size 2.5 cm; 76 (67%) were ER/PR/Her2 negative, 83 (74%) grade 3. Median follow-up was 38 months. 47 (42%) underwent breast conservation therapy (BCT), 66 (58%) had mastectomy, 61 (54%) underwent adjuvant radiation (RT), and 85 (75%) had chemotherapy. At 2 and 5 years, the LRR/DM/OS rates were 12%/15%/90% and 21%/35%/69%, respectively. On Cox regression analysis, only adjuvant RT correlated with reduced LRR [RR 3.1 (1.13-9.88), p = 0.027], while chemotherapy, type of surgery, and T-N stage did not. Only T-stage (p = 0.008) correlated with DM, however chemotherapy, RT, surgery type, and N-stage were not. Univariate analysis demonstrated histologic subtype did not significantly correlate with local (p = 0.54) or distant (p = 0.83) disease control.
This study represents among the largest institutional experiences in the outcomes of MBC. At this time, there does not appear to be a clear histologic subset of MBC which has significantly different clinical outcomes from the other subtypes. Although limited in its sample size, this study shows RT remains important in local-regional control.
化生性乳腺癌（MBC）是一种罕见的侵袭性乳腺癌变体，关于其治疗和预后的数据有限。本研究旨在回顾在我们的三级医疗机构接受治疗的 MBC 患者，重点关注治疗方式和组织学分类的作用。
在获得机构审查委员会批准后，我们通过病理数据库查询了 MBC 诊断患者。所有病例均由专门的乳腺病理学家重新评估，并确认为 MBC 乳腺癌。分析了患者的人口统计学、临床/病理组织学和治疗情况，以及包括局部区域复发（LRR）、远处转移（DM）和总生存（OS）在内的结局。使用单变量和多变量 Cox 比例风险模型评估对结局的影响。Kaplan-Meier 方法估计生存情况。
我们评估了 2002 年至 2013 年间诊断为 MBC 的 113 例患者。中位年龄为 61 岁，中位病理肿瘤大小为 2.5 厘米；76 例（67%）为 ER/PR/Her2 阴性，83 例（74%）为 3 级。中位随访时间为 38 个月。47 例（42%）接受了保乳治疗（BCT），66 例（58%）接受了乳房切除术，61 例（54%）接受了辅助放疗（RT），85 例（75%）接受了化疗。在 2 年和 5 年时，LRR/DM/OS 率分别为 12%/15%/90%和 21%/35%/69%。Cox 回归分析显示，只有辅助 RT 与 LRR 降低相关[RR 3.1（1.13-9.88），p=0.027]，而化疗、手术类型和 T-N 分期则没有。只有 T 分期（p=0.008）与 DM 相关，而化疗、RT、手术类型和 N 分期则没有。单因素分析表明，组织学亚型与局部（p=0.54）或远处（p=0.83）疾病控制均无显著相关性。
本研究代表了 MBC 机构经验中最大的研究之一。目前，MBC 似乎没有一个明确的组织学亚型与其他亚型的临床结局有显著不同。尽管样本量有限，但本研究表明 RT 对局部区域控制仍然重要。
