Microcystic adnexal carcinoma

A patient is described with a tumour of the upper lip which was proved histologically to be a microcystic adnexal carcinoma, probably derived from the outer hair root sheath. This appears to be the eighth in the literature.     

Microcystic adnexal carcinoma

A 55-year-old man presented with an ulcer on the right sole present for 8 years. The ulcer measured 6.5 × 3 cm and affected the entire distal sole of the right foot; the margins were everted and an intermittent serosanguineous discharge was present. The general condition of the patient was good, with findings limited to the ulcerated lesion. There was no history of hypertension, diabetes mellitus, or venous stasis. A biopsy taken from the ulcer edge was interpreted as squamous cell carcinoma, Grade I. A transmetatarsal amputation was carried out and the specimen sent for histopathologic examination. Histologically, the epidermis showed ulcerated areas; adjacent areas showed hyperkeratosis and irregular acanthosis. Keratin cysts containing well-developed lamellar keratin were present in the upper dermis (Fig. 1). Nests and strands of squamous and basaloid cells, having scanty eosinophilic cytoplasm, alternated with the cysts. Areas of ductular differentiation were also noted. The epithelial strands were separated by concentric bands of moderately cellular fibrous tissue in the upper and mid-dermis. In the deeper areas of the tumor the epithelial nests became progressively smaller in size, diminishing to small clusters of two or three cells, and were surrounded by a sclerotic stroma. Cytologic atypia was minimal and no significant mitotic figures were identified. The neoplasm showed extensive infiltration of subcutaneous fat and striated muscle with frequent perineural involvement in the deeper parts. There was no extension to bone or perichondrium. Immunoperoxidase staining carried out for carcinoembryonic antigen (CEA) showed positivity in the lumina and lining cells of the ducts (Fig. 2).
Based upon the classical microscopic appearance, a diagnosis of microcystic adnexal carcinoma was made. The patient has been followed for a period of 3 years with no evidence of tumor recurrence.     

Microcystic adnexal carcinoma with sebaceous differentiation: Three cases

Microcystic adnexal carcinoma (MAC) is a low‐grade malignant tumor of the skin. Histologically, this tumor shows a biphasic pattern, with cords and nests of basaloid cells, as well as keratin horn cysts. This biphasic histological appearance has been interpreted by some authors as a sign of double eccrine and folliculosebaceous‐apocrine differentiation, whereas some other authors defend a solely eccrine differentiation. In this context, sebaceous differentiation in MAC would support the first option. However, there are only 3 cases of MAC with sebaceous differentiation in the literature, and all of them were reported before adipophilin was available, which in the appropriate context (eg, testing clear cells for sebaceous vs eccrine differentiation) is very useful. In this study, we present 3 cases of MAC with focal sebaceous differentiation confirmed by immunoexpression of adipophilin in the sebaceous foci.     

微囊肿性附属器癌一例

微囊肿性附属器癌（microcystic adnexal carcinoma,MAC）又称为硬化性汗腺导管癌（sclerosing sweat duct carcinoma）,属于汗腺癌的一个亚型。MAC是一种以局部侵袭性生长为主,并向汗腺导管方向分化的罕见低度恶性肿瘤,生长缓慢,临床罕见,本文报道一例。     

微囊肿附属器癌

报告1例微囊肿附属器癌.患者男,16岁.额部出现肿块2年余.皮损组织病理检查:真皮内可见大量汗腺导管及角囊肿结构,有基底样细胞条索,细胞无异形性.外科切除肿块后无复发.     

微囊肿附属器癌一例

患者女,43岁,左上唇皮肤斑块2年余.皮肤科检查:患者上唇左上方见一直径约2.5 cm大小的斑块,肤色,表面毛细血管扩张,质硬,边界清楚.皮损组织病理检查:肿瘤位于真皮内,真皮上部可见多个导管结构和少数大的囊腔,真皮中下部可见上皮细胞条索,下部见角囊肿形成,肿瘤细胞侵犯神经和肌肉组织.免疫组化染色:肿瘤性上皮细胞成分细胞角蛋白均阳性,导管及腺腔结构上皮膜抗原阳性,S100染色阳性的神经结构内可见细胞角蛋白阳性的上皮细胞成分浸润.诊断为微囊肿附属器癌.给予手术切除,目前仍在随访中.

Abstract：

A case of microcystic adnexal carcinoma is reported. The patient was a 43-year-old female, who had presented with a plaque on the left upper lip for more than 2 years. Skin examination revealed a demarcated, skin-colored plaque measuring 2.5 cm in diameter with telangiectasia on the surface of the left upper lip. Skin biopsy showed that the tumor lied in the dermis, infiltrating deeply into the underlying nervous and muscle tissue. There were many ductal structures and a small number of ramified glands with apocrine features in the upper dermis, strands of basophilic epithelial component imbedded in a markedly hyalinized stroma in the mid and lower dermis, as well as small and round keratinous cysts in the lower dermis. Immunohistoehemistry revealed strong positive staining of the epithelial components with cytokeratin. The staining for CEA and epithelial membrane antigen (EMA) was noted in the superficial ducts and glands. S-100 stain showed the infiltration of peripheral nerve with cytokeratin-positive epithelial components. A diagnosis of microcystic adnexal carcinoma was made. The patient underwent an excisional surgery and was followed up.     

微囊肿附属器癌1例

报告微囊肿附属器癌1例。患者女,52岁,右侧鼻唇沟的内侧结节2年。检查见右侧鼻唇沟的内侧一1.5cm×2.0cm大的结节,质硬,与皮肤粘连,与皮下组织无粘连,局部皮肤呈淡红色。组织病理检查示:肿瘤位于真皮内,部分扩展至皮下组织,主要由多数鳞状细胞或基底样细胞组成巢状或条索状团块,某些团块内可见角质囊肿或少许透明角质颗粒,有管状结构,衬以单层或双层立方形细胞,腔内含有嗜伊红性物质。部分细胞不典型,有少数核丝分裂像。免疫组化染色示导管结构癌胚抗原(CEA)阳性,瘤细胞索、角质囊肿和管状结构角蛋白染色均阳性。     

Microcystic adnexal carcinoma of the head and neck: Characteristics,treatment, and survival statistics

Studies on microcystic adnexal carcinoma (MAC) survival rates have been limited. This effort examines the association of patient demographics, treatment modalities, and tumor stage with overall survival (OS) in patients with MAC of the head and neck. All cases of MAC with primary sites of the skin of the head and neck, confirmed histologically, and diagnosed from 2004 to 2016 in the National Cancer Database, were analyzed. We utilized Kaplan‐Meier and Cox proportional‐hazard models to analyze the characteristics and survival outcomes of the 415 cases that met the criteria. The mean age of diagnosis was 63.8 years (SD ±15.8). Mean OS was 10.8 years with 5‐ and 10‐year OS being 81.0% and 68.0%, respectively. Women were more frequently affected (59.0%; P < .001). Stand‐alone primary site surgery was the most common treatment (81.4%): 15.9% of patients were treated with postexcision radiation therapy (RT). 18.3% were treated with RT with or without surgery and/or chemotherapy. RT was independently associated with a decreased hazard of death (HR = 0.23; P = .044). MAC of the head and neck disproportionately affects whites, is more common in women, and has the potential to metastasize. Surgical excision is the commonest treatment; our study shows benefit from judicious RT.     

Microcystic adnexal carcinoma with Langerhans cells

A slowly growing, subcutaneous mass in the left eyebrow region of a 54-year-old Japanese woman showed numerous small epithelial cell nests surrounded by a dense desmoplastic stroma. The epithelial cell nests showed partially keratinizing cystic structures containing a small amount of glycogen. Immunoperoxidase staining for carcinoembryonic antigen was positive only in the lumina or on the ductal lining surface of tumor cells; staining for S-100 protein was positive within almost all of the tumor nests. Birbeck granules indicating Langerhans cells were found within some of the cells.     

Microcystic adnexal carcinoma: a diagnostic and therapeutic challenge

ABSTRACT: Microcystic adnexal carcinoma (MAC) is a rare cutaneous neoplasm that is often diagnosed after having been present for a significant period of time. It appears bland on histologic evaluation despite its locally aggressive behavior. Actual skin involvement is significantly more extensive than can be determined clinically and because of this, therapy is challenging. Though metastasis is rare, there have been reports of both regional and distant metastatic disease. Several treatment modalities have been used to date, including standard excision (SE), Mohs micrographic surgery (MMS), irradiation, chemotherapy, and observation. There has also been discussion in the literature regarding techniques than can aid in assurance of clear margins with MMS. We review the literature on MAC, including the various therapeutic options, addressing when one modality may be preferable over others. In general, MMS offers the highest likelihood of clear margins and cure with the fewest procedures.     

Microcystic adnexal carcinoma: report of seven cases including one with lung metastasis

BACKGROUND: Microcystic adnexal carcinoma (MAC) is a rare cutaneous neoplasm, with a high rate of local recurrences. OBJECTIVE: A series of MAC was analyzed and compared to previously published cases. METHODS: Seven cases of MAC were identified in the register of the institution. Medical and pathological records were reviewed. RESULTS: The primary MAC were located on the face in all patients, and 85% were initially misdiagnosed. The mean follow-up duration was 108 months. The recurrence rate was high: 4 patients developed recurrences. In 3 patients, the course of the disease was severe: one of them developed pathologically proven lung metastasis. CONCLUSION: The present study and review of the literature confirm the clinically aggressive evolution of MAC and its rare ability to give rise to metastasis. Long-term clinical follow-ups with imaging investigations are mandatory.     

Microcystic adnexal carcinoma: review of 51 Japanese patients

BACKGROUND: Microcystic adnexal carcinoma (MAC) has been reported to occur predominantly in Caucasians. However, the number of cases in Japanese subjects seems to have recently been increasing. OBJECTIVE: To review the Japanese cases of MAC. METHODS: We collected and analyzed the data of 51 Japanese patients recorded in case reports or abstracts over a number of years. RESULTS: Twenty-five of the cases were reported between 1987 and 1996, and the remaining 26 cases between 1997 and 2000. Forty-three lesions were located on the face, 2 on the scalp, 2 on the chest, 1 on the axilla, 1 on the buttock, 1 on the palm and 1 on the toe. One of the above occurred at the site of previous radiotherapy. Fifteen tumors were initially misdiagnosed histopathologically. CONCLUSION: Our review shows that MAC also occurs in the Japanese, in whom it may be more common than previously observed.     

Microcystic adnexal carcinoma with lymph node metastasis

Microcystic adnexal carcinoma (MAC) affects predominantly the face and seldom metastasizes. We report a case occurring in the axilla of a 63-year-old male. Histology revealed the characteristic features of MAC. Eleven months after the excision, he underwent a reexcision with wide margins because of local recurrence. Histologically, the central area of the recurrent lesion revealed the typical histologic features of MAC, and the periphery showed a proliferation of irregular duct-like and glandular structures with a mixed pattern. Two lymph nodes that were not adherent to the tumor had metastatic tumor cells. The present case confirms that MAC can metastasize, although it may also be hypothesized that the recurrent lesion represented transformation into a higher-grade carcinoma.     

Microcystic adnexal carcinoma: a light microscopic, immunohistochemical and ultrastructural study

We report a case of microcystic adnexal carcinoma (MAC) occurring on the upper lip of an 82-year-old woman. Microscopically the tumor showed both pilar and sweat gland differentiation, involved the entire dermis and subcutaneous tissue, and invaded perineural spaces. Immunoperoxidase studies revealed carcinoembryonic antigen to be present in the ductal lining cells and in the amorphous content in the lumen, confirming sweat gland differentiation. The S-100 protein was positive in dendritic cells within the solid cell nests, but negative in cells lining cystic spaces. Ultrastructural study confirmed that the neoplasm was composed of two components, with pilar and eccrine differentiation. The former showed concentric layers of squamous epithelial cells with well-developed desmosomes and cytofilaments. The latter had ductal and alveolar structures; the ultrastructural features included: i) numerous villous folds of plasma membrane to interdigitate each other by focal desmosomes, ii) aggregates of cytofilaments, and iii) basally located myoepithelial cells which were separated from the surrounding stroma by rather thick basement membrane. In addition, distinct amyloid deposition was also observed on ultrastructural examination. To our knowledge, amyloid deposition has not been previously reported in MAC.     

Microcystic adnexal carcinoma with germinative follicular differentiation

Microcystic adnexal carcinoma (MAC) is a low‐grade adnexal carcinoma with controversial lines of differentiation. We present here an example of MAC showing histopathologic findings of germinative follicular differentiation in the form of solid aggregates of trichoblastoma intermingled with neoplastic aggregates of MAC. Immunohistochemical findings, showing positivity for PHLDA1 and negativity for BerEp4 in neoplastic aggregates of trichoblastoma, also supported a germinative follicular differentiation. Follicular differentiation in MAC supports an apocrine line of differentiation for this neoplasm.     

Microcystic adnexal carcinoma: the first reported congenital case

Microcystic adenexal carcinoma is a rare, locally aggressive, malignant appendage tumor also known as sclerosing sweat duct carcinoma. Since widespread recognition of microcystic adenexal carcinoma as a distinct clinicopathologic entity, approximately 300 total cases have been reported in the literature, with only eight previous cases reported in children under the age of 18, with no reported cases in patients younger than 6 years old. Our patient is unique in that the lesion was present at birth, making this the youngest case of microcystic adenexal carcinoma reported.