乳腺肌母细胞亚型组织细胞样癌

癌像肌母细胞，胞浆红染色，核偏位

在纤维中浸润

浸润达乳头真皮层

侵犯神经

侵犯血管壁

Histiocytoid breast carcinoma: an enigmatic lobular entity。

组织细胞样乳腺癌是一种难以诊断的癌。

ABSTRACT：
Histiocytoid breast carcinoma is an uncommon entity  that is mostly regarded as a variant of lobular cacinoma. Its occurrence with apocrine lobular carcinoma in situ and consistent expression of gross cystic disease fluid protein 15 suggest apocrine differentiation. Its recognition is often challenging, particularly when histiocytoid tumour cells occur in a metastatic site before the primary diagnosis of breast carcinoma, or in limited core biopsy or cytology material. In the breast, its bland histological appearances can lead to a benign diagnosis. Clues to the correct conclusion include finding tumour cells with more cytological atypia, the presence of cytoplasmic vacuoles and secretions, coexistence with more traditional invasive lobular carcinoma patterns and/ or lobular neoplasia, and the use of immuohistochemistry to confirm their epithelial nature. Close clinicoradiological correlation and awareness of histological mimics are needed to achieve an accurate diagnosis of this nenigmatic condition that should be appropriately subsumed within the invasive lobular histological subtype.

摘要：组织细胞样乳腺癌是一种罕见的肿瘤，一般被认为是小叶癌的亚型，它常常伴有原位大汗腺小叶原位癌，并且常常表达GCDFP-15，因此被认为有大汗腺分化。这种癌的诊断是有挑战性的，特别是在没有发现原发的乳腺组织细胞样癌前，以转移部位为首发症状时，或者是穿刺活检组织或细胞学穿刺组织诊断时。在乳腺组织中，因为组织细胞样癌的组织形态温和，常常被误诊为良性肿瘤。要做出正确诊断需要观察到肿瘤细胞的异型性，细胞胞浆中有空泡和分泌物，伴随有经典的乳腺小叶癌或小叶肿瘤，同时免疫组化证明这些细胞是上皮性的。组织细胞样癌的临床特点和组织学特点与乳腺浸润性小叶癌相似，因此被归入乳腺小叶癌的一个亚型。

前言：

Histiocytoid breast carcinoma was first described by Hood et al1 in 1973, in which 13 cases of tumour metastatic to the eyelid were documented, and eight of these metastases featured histiocytoid appearances that caused diagnostic challenges. It has since been variously ascribed to lobular or apocrine carcinoma, as well as being linked to lipid-rich carcinoma,with some authors advocating that it be considered a distinct entity. Despite the several small series and individual case reports that have been presented in the literature, there is still no universal agreement on how this enigmatic tumour ought to be specifically classified, or whether its recognition has prognostic or predictive significance.Its mimicry of benign and other conditions, however, is well recognised, and remains a pitfall for histopathologists, especially when assessing limited material on core biopsy or cytology.
In this review, we appraise the information on histiocytoid breast carcinoma since its initial
description and discuss differential diagnoses that may pose interpretive issues.

组织细胞样癌最早是1973年HOOD等报道的，他总结了13例转移到眼睑的肿瘤，其中有8例有组织细胞样形态而导致误诊。乳腺组织细胞样癌的来源不同专家有不同观点，有人认为是小叶癌，有人认为是大汗腺癌，还有人认为是富于脂汁的乳腺癌，有些专家干脆提议把乳腺组织细胞样癌直接定为一种特殊类型的乳腺癌。尽管目前乳腺组织细胞样癌有少量的系列报道和个案报道，但是对这个神秘的肿瘤如何分类，以及它是否预示着特殊的预后还没有形成共识。它很像一个良性病变，对于病理专家来说是一个陷阱，特别是在穿刺活检组织中诊断非常容易漏诊。

在本文中，我们评价乳腺组织细胞样癌从一开始到现在的资料信息，来讨论其诊断和鉴别诊断。

正文内容要点：

1、有些专家认为乳腺组织细胞样癌是富于脂汁的癌，但脂肪染色是阴性的，粘液染色是阳性的，因此乳腺组织细胞样癌不是富于脂汁的癌。

2、乳腺组织细胞样癌表达GCDFP15，不表达E-cadherin，因此认为是有大汗腺分化的小叶癌来源。

3、镜下特征：肿瘤细胞粘附性差，一般在纤维结缔组织中散在分布，或围绕导管靶环样分布。胞浆红染，或空泡状，核小，卵圆形，均质，核分裂罕见。