人类原始抗原（CD34）在毛发上皮瘤和基底细胞癌中的表达

毛发上皮瘤是一种向毛囊分化的良性肿瘤，常与基底细胞癌混淆。应用人类原始抗原（ＣＤ３４）检测７例毛发上皮瘤和１２例基底细胞瘤中表达，结果：在正常皮肤血 皮细胞、血管周围和真皮内梭形细胞、毛囊、小汗腺周围梭形细胞阳性。毛发上皮瘤瘤团周围梭形细胞阳性，而基底细胞癌外周间质阴性，说明ＣＤ３４染色有助于临别这两种肿瘤。     

毛发上皮瘤23例临床病理分析

毛发上皮瘤（trichoepithelioma),又名囊性腺样上皮瘤（epithelioma adenoides cystieum),是一种皮肤附属器肿瘤,起源于多分化潜能的基底细胞,并有向毛发分化的趋势。现将笔者1986-2004年4月诊治的23例毛发上皮瘤报告如下。     

β-连环蛋白在毛母质瘤及毛发上皮瘤中的表达

目的: 检测β-连环蛋白(β-catenin)在毛母质瘤及毛发上皮瘤中的表达.方法: 应用免疫组织化学法检测20例正常皮肤、20例毛母质瘤及10例毛发上皮瘤中β-连环蛋白的表达.结果: β-连环蛋白在正常皮肤角质形成细胞中主要表达于细胞膜, 15例毛母质瘤和8例毛发上皮瘤的表达位于胞质和/或胞核.结论: β-连环蛋白可能参与毛基质细胞的增殖和成熟的调控,它的异常表达在毛囊发育和向毛囊分化肿瘤的发生中可能起重要作用.     

16例单发性毛发上皮瘤临床与病理观察

目的：探讨单发性毛发上皮瘤的临床表现、病理特征、诊断要点及预后。方法：所有病例行局部皮肤肿瘤切除,常规组织切片、染色,随访观察2年。结果：16例病理诊断为单发性毛发瘤病例中,其中有14例临床误诊。15例术后无复发,1例继发鳞癌。组织病理有典型的形态特征,镜下与基底细胞癌相似,可表现有基底样细胞组成的小叶结构或团块结构,瘤巢周边细胞呈栅状排列,但有向毛发分化的倾向和角质囊肿形成等。结论：单发性毛发上皮瘤临床极易误诊,组织病理学特征是本病确诊的主要依据。     

毛发上皮瘤的皮肤影像学特征分析

【摘要】 目的 比较毛发上皮瘤的反射式共聚焦显微镜（RCM）和皮肤镜特征与组织病理学特征。方法 2017年1月至2018年12月于武汉市第一医院皮肤科门诊收集经组织病理学确诊的毛发上皮瘤患者23例，采集RCM、皮肤镜图像，对比其与组织病理学特征的一致性。结果 23例中，男5例，女18例，年龄（39.5 ± 22.1）岁。组织病理特征：肿瘤界限清楚，周围有丰富的纤维基质；肿瘤团块为多数基底样细胞集合或相互交织的基底样细胞索，周边细胞呈栅栏样排列；肿瘤细胞不同程度地向毛乳头分化；可见不等数量的角囊肿。RCM特征：23例患者中8例可见真表皮交界处芽蕾样下延的条索状细胞，有栅栏样排列趋势；18例可见真皮层散在分布结节状似有分叶的瘤团，与周围组织无收缩间隙，呈扩大的低回声结构；16例瘤团周围有中高折光的无定形基质包绕；16例患者可见特征性的疑似原始分化毛乳头结构；20例可见清晰的角囊肿。皮肤镜特征：20例可清晰观察到珍珠白色、均质状结构，10例线状毛细血管扩张。结论 毛发上皮瘤的RCM特征与组织病理具有较高一致性，可作为辅助诊断及鉴别诊断的有效方法。     

毛囊皮脂腺囊性错构瘤研究进展

临床上，毛囊皮脂腺囊性错构瘤比较少见，缺乏典型特征，是一种不对称，好发于面部的肤色丘疹或结节。病理学上是以毛囊皮脂腺组织和间叶细胞成分增生为主的皮肤附属器错构瘤，主要与皮脂腺毛囊瘤、皮样囊肿相鉴别。免疫组化结果与瘤体内上皮或非上皮成分有关，无特异性。概述毛囊皮脂腺囊性错构瘤的临床表现、诊断标准、免疫组化及治疗方面的研究进展。     

多发性家族性毛发上皮瘤报道

多发性家旌性毛发上皮瘤（multiple farnilial trichaepithelioma，MFT），属于常染色体显性遗传性皮肤病，来源于毛母细胞并不同程度向毛囊分化的良性肿瘤。目前已证实多发性家庭性毛发上皮瘤的基因定位于9P21。     

8例汗腺瘤临床及组织病理分析

目的：探讨皮肤汗腺瘤的临床、组织病理及免疫组化特征。方法：对8例皮肤汗腺瘤的临床、组织病理及免疫组化结果进行回顾性分析。结果：8例患者中,男5例,女3例,平均年龄51.4岁（25～66岁）。发病部位：头部及四肢各3例,躯干2例。临床表现为皮下孤立、生长缓慢的囊性和（或）实性结节,7例境界清楚,1例界限不清。组织病理检查显示该肿瘤主要由多边形鳞状细胞样细胞和透明细胞组成,8例均可见导管分化,4例透明细胞变性,2例鳞状分化,1例见顶浆分泌现象。免疫组化显示肿瘤细胞主要表达细胞角蛋白（CK）、CK5/6、p63和P40;汗腺导管上皮膜抗原（EMA）、癌胚抗原（CEA）阳性。结论：皮肤汗腺瘤是一种少见皮肤附属器良性肿瘤;组织病理表现多样。     

间充质干细胞诱导分化为皮肤附属器的研究进展

临床患者由于外伤、严重烧伤及瘢痕切除等导致大面积皮肤缺损时面临自体皮肤移植供体不足的难题,且组织工程皮肤因皮肤附属器的缺失,导致汗液无法排出、毛发丧失等使患者生存质量和心理健康受到严重影响。随着再生医学的发展,间充质干细胞因其来源丰富、低免疫原性、体外扩增能力强及具有多向分化潜能的优势逐渐成为组织工程皮肤种子细胞来源的研究热点。本文就MSCs向毛囊、汗腺、皮脂腺等皮肤附属器的诱导分化作一综述。     

角化型基底细胞癌与毛发上皮瘤细胞形态定量分析

角化型基底细胞癌为皮肤的一种恶性肿瘤，毛发上皮瘤为良性肿瘤，两者在光镜下的组织病理具有形态相似的基底样细胞团索，有时易于混淆，给病理诊断带来困难。本研究采用大型自动化多功能图像分析仪（ＩＡＩ），以角化型基底细胞癌及毛发上皮瘤的石蜡组织切片进行细胞形态学的计量分析，利用形态计量的某些参数，将这两种组织病理易于混淆的良、恶性肿瘤进行比较和鉴别，以寻求一种较为客观的病理诊断方法。一、资料和方法标本收集：选择我科历年来经临床及组织病理确诊的角化型基底细胞癌及毛发上皮瘤各５例患者的蜡块，将各蜡块制成４ｕｍ…     

p75 Neurotrophin receptor differentiates between morphoeic basal cell carcinoma and desmoplastic trichoepithelioma: insights into the histogenesis of adnexal tumours based on embryology and hair follicle biology

Background Tumour development is frequently described in the basic pathology literature as a recapitulation of embryogenesis. However, a link between the embryology of the skin and the histogenesis of adnexal tumours has been largely overlooked. The low‐affinity p75 neurotrophin receptor (p75NTR) has a profound role in hair follicle biology. We therefore speculated that it is involved in the histogenesis of follicular adnexal tumours. One of the most challenging diagnoses in dermatopathology is differentiating morphoeic basal cell carcinoma from desmoplastic trichoepithelioma. Objectives To describe the expression pattern of p75NTR during cutaneous embryogenesis, in the adult hair follicle and in morphoeic basal cell carcinoma and desmoplastic trichoepithelioma. Methods Evaluation of the staining pattern for p75NTR was performed using standard immunohistochemical techniques. For comparison, we examined staining for cytokeratin 20 which highlights Merkel cells. Results All 17 desmoplastic trichoepitheliomas were immunoreactive with > 80% of the cells stained, whereas 12 of the 14 (86%) morphoeic basal cell carcinomas were p75NTR negative. In the two positive cases of morphoeic basal cell carcinoma < 30% of cells were labelled. In the late bulbous hair peg stage and in the postnatal anagen hair follicle p75NTR highlights the outer root sheath. Conclusions Our results support the classification of desmoplastic trichoepithelioma as a follicular hamartoma mimicking the outer root sheath. In contrast, the lack of p75NTR expression in morphoeic basal cell carcinoma favours a concept of this tumour as a more primitive follicular lesion with the characteristics of a carcinoma and not a hamartoma. We suggest including p75NTR as a tool in the differential diagnosis between morphoeic basal cell carcinoma and desmoplastic trichoepithelioma.     

PHLDA1 (TDAG51) is a follicular stem cell marker and differentiates between morphoeic basal cell carcinoma and desmoplastic trichoepithelioma

Background Morphoeic basal cell carcinoma (BCC) and desmoplastic trichoepithelioma can often be difficult to differentiate on routine sections and few reliable immunohistochemical markers are currently available. Recent cDNA microarray studies revealed the pleckstrin homology‐like domain, family A, member 1 protein (PHLDA1) as a highly reliable marker of the hair follicle stem cells. Given the differentiation of trichoepithelioma along the follicular lineage and the proposed role of PHLDA1 as a follicular stem cell marker, we examined the staining pattern of PHLDA1 in the desmoplastic variant of trichoepithelioma and in its differential diagnostic conundrum, morphoeic BCC. Objectives To describe the expression pattern of PHLDA1 in morphoeic BCC and desmoplastic trichoepithelioma. Methods Evaluation of the staining pattern for PHLDA1 was performed using standard immunohistochemical techniques. For comparison reasons, we analysed staining for PHLDA1 in normal skin structures with particular reference to the hair follicle. Results With the exception of one case, all 16 desmoplastic trichoepitheliomas were immunoreactive with more than 80% of the cells stained, whereas all 14 morphoeic BCCs were PHLDA1‐negative with the exception of ulcerated tumours. In the latter, the tumour islands close to the ulcer were PHLDA1‐positive whereas the deeper located tumour portions remained immunonegative. PHLDA 1 was prominently expressed in the hair follicle bulge of terminal and vellus hair follicles. Conclusions The hair follicle bulge marker PHLDA1 differentiates between desmoplastic trichoepitheliomas and nonulcerated examples of morphoeic BCCs. We suggest incorporating PHLDA1 in the diagnostic work‐up of difficult to differentiate basaloid tumours.     

Desmoplastic trichoepithelioma and intradermal nevus: a combined malformation

We studied 13 desmoplastic trichoepitheliomas associated with intradermal nevi. Ten intradermal nevi were found among 76 new cases of desmoplastic trichoepithelioma (13%); three additional examples of the combined malformation were seen in consultation. Clinically, desmoplastic trichoepithelioma associated with an intradermal nevus was typically a small, firm or hard, sometimes annular, nodule on the face, particularly the cheek, of a relatively young woman. Microscopically, the combined malformation contained narrow strands of basaloid cells and keratinous cysts in a desmoplastic stroma, intimately mixed with intradermal nests of nevocytes. Melanocytic nevi have been associated with epidermal hyperplasia resembling seborrheic keratoses, follicular cysts, trichostasis spinulosa, syringomas, basal cell carcinomas, and hair follicle formation on the soles. The frequency of the occurrence of intradermal nevus with desmoplastic trichoepithelioma and the close anatomic association of the two elements may indicate that this combined malformation is another example of epithelial induction by melanocytic nevi.     

Desmoplastic trichoepithelioma: presentation of two cases

Trichoepithelioma is a benign neoformation with hair follicle differentiation that may clinically present in solitary, multiple or desmoplastic form. From a histopathological standpoint, it poses some diagnostic difficulties with basal cell carcinoma. We present two cases of desmoplastic trichoepithelioma, a rare adnexal tumor whose incidence is estimated at 2 per 10,000. Desmoplastic trichoepithelioma is a benign lesion, clinically and histologically similar to other dermatoses, and presents a true diagnostic challenge.     

Basaloid follicular hamartoma: three cases with localized and systematized unilateral lesions

Two patients having a localized plaque of alopecia on the scalp, and one with a systematized unilateral epithelial nevus exhibited a histologically distinctive form of follicular hamartoma. In the affected areas individual hair follicles were replaced, or were associated with solid strands and branching cords of undifferentiated basaloid cells, filled in between by fibrous stroma resembling either a miniature premalignant fibroepithelial tumor of Pinkus, a small trichoepithelioma, or a basal cell epithelioma. The relation between these 3 patients and cases reported as linear unilateral basal cell nevus with comedones and generalized hair follicle hamartoma associated with myasthenia gravis is discussed.     

Immunohistochemical analysis of cytokeratin expression in various trichogenic tumors.

The immunophenotypes, especially expression of cytokeratins, in 13 cases of trichogenic tumors were examined to investigate their histogenesis. Four cases of multiple trichoepithelioma, five cases of classical solitary trichoepithelioma, one case of desmoplastic trichoepithelioma, one case of trichogenic trichoblastoma, one case of trichoblastic fibroma, and one case of giant solitary trichoepithelioma were retrieved. The immunoreactivities of the epithelial nests and the keratinous cysts in these tumors were similar to those of the outer root sheath and the infundibulum of normal hair follicles, respectively. From the comparative studies of the immunophenotypes with those of normal hair follicles, we speculated that all trichogenic tumors differentiate mainly toward the outermost layer of the outer root sheath between the lower part of the permanent portion and the upper part of the transient portion and some parts of them differentiate toward various other parts of the follicles. Although differentiation toward the other follicular structures can vary from case to case, there is no particular staining pattern specific for each kind of trichogenic tumor and no significant differences in immunoreactivity among them. Our observations support a recent notion that all neoplasms of follicular germinative cells should be grouped as a single entity.     

Generalized hair follicle hamartoma: the third case report in association with myasthenia gravis

A 29-year-old woman, referred because of the development of diffuse papules and plaques on the face and progressive hair loss, was found to have generalized hair follicle hamartoma, a very rare condition previously described in only two female patients. All three patients also suffered from myasthenia gravis. The histological appearance of both the involved and uninvolved skin was similar to trichoepithelioma.     

Trichoepithelioma with "monster" stromal cells

Trichoepithelioma is a benign tumor of trichogenic origin which appears predominantly in childhood or in young adults. Different forms have been described according to clinical and histological features. The authors report a unique variant of trichoepithelioma arising on the limb of a 27-year-old man. The tumor was characterized by the mixture of an atypical fibroxanthomatous proliferation and basaloid epithelial strands of trichoepithelioma. Such histological features have not been previously reported. It raises the question of an additional variant of hair follicle tumor with a mixed epithelial and mesenchymal proliferation.     

Involucrin expression in skin appendage tumours

The expression of involucrin was examined in 23 skin tumours of hair follicle origin, 17 tumours of sweat gland origin and three tumours of unknown origin, using an immunoperoxidase technique. All tumours from the hair follicle showed a positive reaction for involucrin. In particular keratoacanthoma and the squamous eddies in various tumours stained strongly. Trichofolliculoma, trichilemmoma and pilomatrixoma exhibited characteristic staining patterns which resembled those in the normal hair follicle. On the other hand the majority of the tumours of sweat gland origin did not stain, with restricted positive reactions in areas showing lumen formation or squamous metaplasia. In contrast to the lack of staining in syringoma, a positive reaction was observed in desmoplastic trichoepithelioma, which is histologically similar to syringoma. Clear cell acanthoma, the origin of which is still controversial, showed a staining pattern which indicated that its origin may not be in the sweat gland. These results suggest that testing for involucrin in skin appendage tumours may be very useful for understanding the kinetics of maturation as well as in determining the origin of the tumours.