CD34+ fibroblasts are constitutive stromal components of virtually all organs, including the mammary stroma, being involved in matrix synthesis, antigen presentation, and tumor-associated stromal remodeling. The most common subtype of invasive breast carcinoma, invasive carcinoma of no special type (IBC-NST), is known for its stromal loss of CD34+ fibroblasts while acquiring alpha smooth muscle actin-positive (α-SMA+) myofibroblasts, i.e., cancer-associated fibroblasts (CAF), whereas invasive lobular carcinoma (ILC) displays partial preservation of CD34+ fibroblasts. The aim of this study was to evaluate the prognostic relevance of stromal CD34+ fibroblasts and α-SMA+ myofibroblasts in an extended collection of ILC. A total of 133 cases of ILC, primarily resected between 1996 and 2004 at University Hospital Marburg, were examined semiquantitatively for stromal content of CD34+ fibroblasts and α-SMA+ myofibroblasts. Partial preservation of CD34+ fibroblasts in the tumor stroma of ILC was confirmed. Absence of CD34+ fibroblasts in the tumor stroma significantly correlated with the presence of α-SMA+ myofibroblasts (p = 0.010), positive lymph node status (p = 0.004), and pN stage (p = 0.006). Stromal loss of CD34+ fibroblasts was significantly associated with lower overall and disease-free survival rates (p = 0.012 and 0.013, respectively). Multivariate analysis adjusted for pT and pN stage revealed stromal loss of CD34+ fibroblasts as independent prognostic parameter (p = 0.05). To our knowledge, this is the first report defining prognostically relevant stromal subtypes of ILC with long-term follow-up. Future research targeting the potential diagnostic and therapeutic implications of CD34+ fibroblasts and CAF in breast cancer, especially ILC, is a promising field of interest.

中文翻译：

---

乳腺浸润性小叶癌中基质CD34阳性成纤维细胞丢失的预后相关性。

CD34 +成纤维细胞实际上是包括乳腺基质在内的所有器官的组成性基质成分，参与基质合成，抗原呈递和与肿瘤相关的基质重塑。浸润性乳腺癌最常见的亚型，无特殊类型的浸润性癌（IBC-NST），因其CD34 +成纤维细胞的基质丢失而获得α平滑肌肌动蛋白阳性（α-SMA+）肌成纤维细胞，即与癌症相关成纤维细胞（CAF），而浸润性小叶癌（ILC）显示CD34 +成纤维细胞的部分保存。这项研究的目的是评估大量ILC中基质CD34 +成纤维细胞和α-SMA+肌成纤维细胞的预后相关性。共有133例ILC病例，主要在1996年至2004年之间于马尔堡大学医院切除，半定量检测CD34 +成纤维细胞和α-SMA+肌成纤维细胞的基质含量。证实ILC的肿瘤基质中CD34 +成纤维细胞的部分保存。肿瘤基质中CD34 +成纤维细胞的缺乏与α-SMA+肌成纤维细胞（p = 0.010），淋巴结阳性（p = 0.004）和pN分期（p = 0.006）的存在显着相关。CD34 +成纤维细胞的基质损失与较低的总体生存率和无病生存率显着相关（分别为p = 0.012和0.013）。调整pT和pN阶段的多变量分析显示，CD34 +成纤维细胞的基质丢失是独立的预后参数（p = 0.05）。就我们所知，这是第一个通过长期随访确定ILC的预后相关基质亚型的报告。