Mucinous metaplasia of apocrine duct

Mucinous Syringometaplasia: Surrounding Acanthosis With Hyperkeratosis Tends to Conceal the Change

A 57-year-old man had a 2-year history of a painful nodule on the right sole. Physical examination revealed an 8 × 8 mm hyperkeratotic plaque with a central fissure. Excisional biopsy disclosed epithelial invagination surrounded by the acanthotic epidermis with parakeratotic hyperkeratosis and focal hypergranulosis. The invaginated epithelium lacked a cornified layer and was composed of a mixture of small basaloid squamous cells and goblet cells showing tubular structures. The patient was diagnosed with mucinous syringometaplasia. Our literature review established that surrounding acanthosis with hyperkeratosis typically tends to conceal mucinous syringometaplastic changes. Because mucinous syringometaplasia often presents as an asymptomatic papule/nodule with no distinct ulcer, fissure, or depressed area, cases may be overlooked.

Eruptive Multifocal Cutaneous Mucinous Cysts

Cutaneous cysts lined by mucinous epithelium are rare entities. We report an unusual case of a 60-year-old female patient who presented with a 2-month history of eruptive cystic papules on her right thigh. Histopathologic study showed multiple, multiloculated cysts located in the dermis lined by nonciliated mucinous epithelium. The cyst lining was positive for AE1/AE3, CK7, CK20, and GCDFP15. Patchy positivity was noted on the p53 stain. Attenuated Sox10 positive cells were identified, raising the possibility of sweat duct origin; however, no myoepithelial layer was identified by p63 staining. Mullerian markers, including ER, PR, WT1, and Pax8, were negative. We propose this as a unique case that may represent mucinous metaplasia of a cystic sweat duct lesion. Here, we review the literature of mucinous and other glandular cutaneous cysts.

Mucinous hidradenoma in a child-A case report and review of the literature

Hidradenomas are benign tumors of the sweat glands that are rarely reported in childhood. The presence of mucinous change in hidradenomas, which consists of variable numbers of mucin-rich goblet cells, is occasionally observed in some adult clinical practices. However, it has not been previously reported in the pediatric population. Herein, we present a unique case of a mucinous hidradenoma presenting on the thigh of a 3-year-old boy. The clinical presentation and histological features of the case, along with a literature review of published case reports of pediatric hidradenomas are described. We present this case in order to highlight this variant of hidradenoma and to reinforce its inclusion in the differential diagnosis of neoplasms/conditions of childhood with mucinous differentiation.

Syringometaplasia: variants and underlying mechanisms

Syringometaplasia is an adaptive, benign, metaplastic cellular process that affects the eccrine ducts and glands in response to a variety of physiological or pathological stimuli. Different subtypes of syringometaplasia have been described, including the squamous, mucinous, and adenomatous types. These metaplastic changes have been reported in association with chemotherapeutic agents, as well as with a variety of skin disorders including multiple infectious, neoplastic, and inflammatory skin diseases. In this review, we attempt to shed light on the different patterns of syringometaplasia, its pathogenesis, the plethora of skin conditions in which it may be observed, and the differential diagnoses that should be considered.

Apocrine mixed tumor of the skin (“mixed tumor of the folliculosebaceous-apocrine complex”)

BACKGROUND

A systematic analysis of the entire spectrum of various forms of differentiation and metaplastic epiphenomena in cutaneous apocrine mixed tumor (AMT) has never been performed.

OBJECTIVE

The purpose of our study was to study a large number of cutaneous mixed tumors so as to fully characterize the entire spectrum of differentiations and metaplastic changes that may occur in the epithelial, myoepithelial, and stromal components of AMT.

METHODS

This article reports a light-microscopic study of 244 cases of cutaneous AMT, complemented by a literature review.

RESULTS

All types of differentiation along the lines of the folliculosebaceous-apocrine unit can be seen in AMT. The spectrum of metaplastic changes in the epithelial components includes squamous metaplasia, mucinous metaplasia, oxyphilic metaplasia, clear cell change, columnar metaplasia, hobnail metaplasia, and cytoplasmic vacuolization. The following changes in the myoepithelial component were documented: clear cell change, hyaline cells, plasmacytoid cells, spindling, and collagenous spherulosis. Stromal alterations included chondroid metaplasia, osseous metaplasia, and adipose metaplasia.

LIMITATIONS

This study utilizes tissue specimens that mainly came as consultations; therefore some inherent selection bias exists.

CONCLUSIONS

AMT displays a wide range of differentiation and metaplastic changes in its epithelial, myoepithelial, and stromal components. These phenomena are not mutually exclusive. When unduly prominent, they may present diagnostic pitfalls. Our findings corroborate those of previous publications, stressing the remarkable diversity of differentiation and metaplasias that may be found in cutaneous AMT. We propose that the most appropriate name for these lesions is "mixed tumor of the folliculosebaceous-apocrine complex."

Sebaceous Carcinoma Arising in Nevus Sebaceus of Jadassohn: A Clinicopathological Study of Five Cases

The authors report a small series of sebaceous carcinoma developing in nevus sebaceus of Jadassohn (also known as organoid nevus) and analyze similar cases reported in the literature. All of our patients were females (age range 57-71 years; median 60 years) who had the organoid nevus on the scalp, face, or nuchal area, the rest of which was recognized clinically and/or histologically. All sebaceous carcinomas manifested unquestionable architectural (asymmetry, invasive growth) and cytological features of a carcinoma (cellular and nuclear pleomorphism, plentiful atypical mitoses, necroses en masse), demonstrated unambiguous sebaceous differentiation in the form of mature sebocytes, and lacked other differentiations. The sebaceous carcinoma was always accompanied by other benign or malignant adnexal lesions such as sebaceoma, syringocystadenoma papilliferum, syringocystadenocarcinoma papilliferum, trichoblastoma, tricholemmoma, desmoplastic tricholemmoma, or syringoma. In three cases, prominent mucinous metaplasia of sweat ducts and glands was seen. In two of these cases, sweat ducts exhibited hyperplastic changes. The analysis of the previously published material and our cases indicates that sebaceous carcinoma arising in organoid nevus has a female predilection and tends to occur in elderly patients. It may involve any site where nevus sebaceus typically occurs. Clinically, the tumor presents as a solitary nodule, ulcerated tumor, or mass, often with a recent history of rapid growth. It may arise alone, but it occurs more frequently as part of multiple benign and malignant adnexal tumors. The lesion does not seem to be associated with Muir-Torre syndrome. The rest of organoid nevus is usually recognized both clinically and microscopically, although large tumors may overgrow and mask the nevus. The tumor seems to be a low-grade carcinoma in terms of clinical behavior.

Mucinous hidradenoma: a report of three cases

Mucinous cutaneous adnexal tumors are an uncommon occurrence. We describe three cases of mucinous hidradenoma characterized by diffuse and prominent mucinous cell proliferation and discuss the relevant literature. The patients (two men and one woman) ranged in age from 32 to 72 years. The lesions were completely excised, and all patients were alive without evidence of disease (follow-up interval 3-4 years). Case 1 presented as a 1.3-cm eyelid nodule and histology showed a mucinous apocrine hidradenoma with a proliferation of mucinous cells and apocrine glands. Case 2, from the shoulder of a 40-year-old man, was a 2.5-cm well-circumscribed nodule composed of hyperplastic villoglandular proliferation of mucinous cells with focal squamous whorls and focal columnar glandular cells showing decapitation secretion. The tumor was also interpretated as a mucinous hidradenoma, most likely of follicular-apocrine origin. Case 3 was a 3.0-cm scalp nodule. The histology showed a mucinous clear-cell hidradenoma composed of numerous mucinous glands amidst small squamous cells with clear cytoplasm and a hyalinized fibrovascular stroma.

Mucinous metaplasia of the vulva in a case of lichen sclerosus. A case report

Mucinous metaplasia of the genital area is a rare condition characterised by the emergence of mucin containing cells in stratified squamous epithelium. This report describes a unique case of benign mucinous metaplasia of the vulva associated with lichen sclerosus in a 60 year old woman. Histopathology revealed cervical type metaplasia with otherwise typical lichen sclerosus. This report discusses the pathogenesis and differential diagnosis of mucinous epithelium.

Eccrine mucinous metaplasia associated with an apocrine cystadenoma

Mucinous metaplasia occurs uncommonly in cutaneous pathology, usually at specialized anatomic locations (genitalia, palms, and soles) and within restricted pathologic contexts (inflammation and trauma). Here, we report a unique case of eccrine mucinous metaplasia associated with an apocrine cystadenoma. A 13-year-old girl had an asymptomatic, 4-mm nodule on the chest. Histopathology demonstrated a typical apocrine cystadenoma in the upper and middle dermis. Adjacent to this lesion was a cluster of coiled eccrine secretory glands, of which the inner layer was almost entirely replaced by benign-appearing cells containing abundant, non-sulfated acid mucopolysaccharides. At 10 months' follow up, there was no recurrence. Our case demonstrates that, very uncommonly, mucinous metaplasia may be associated with a pathogenetically separate, adjacent proliferative adenomatous lesion, in this instance, an apocrine cystadenoma.