Staining of eccrine and apocrine neoplasms and metastatic adenocarcinoma with IKH-4, a monoclonal antibody specific for the eccrine gland

Sox10 and DOG1 Expression in Primary Adnexal Tumors of the Skin

Primary skin adnexal tumors can be challenging to classify and must be discerned from cutaneous adenocarcinoma metastases from various sites. We evaluated expression of Sox10 and DOG1 in normal cutaneous adnexa and in 194 primary skin adnexal tumors, and compared their performance in discriminating primary skin adnexal tumors from cutaneous metastatic adenocarcinomas with that of p40 and p63. In normal skin adnexa, we noted Sox10 expression in both the secretory and myoepithelial cells in eccrine glands, but only in myoepithelial cells in apocrine glands. DOG1 demonstrated canalicular expression in eccrine glands, and weak expression in myoepithelial cells of apocrine glands, germinative cells of sebaceous glands, and outer root sheath of follicular infundibulum. Sox10 was expressed in 100% of cylindromas and spiradenomas, and in variable frequency in other benign and malignant tumors of sweat glands. DOG1 was positive in most cylindromas (87.5%), in only 10.5% of spiradenomas, and was variably expressed in other benign and malignant tumors of sweat glands. All syringomas (n = 20) were negative for Sox10 and DOG1. One out of the 33 follicular neoplasms was positive for Sox10 and DOG1 (3%). All sebaceous neoplasms were negative for Sox10, and 28.1% of them were positive for DOG1. Sox10 was specific (91.9%) but not sensitive (28.4%) for primary skin origin, and was far less accurate (38.5%) than p63 or p40 (95.5% accuracy). Combining Sox10 with p63 or p40 showed only very minimal gain in accuracy (96%). DOG1 expression in tumors showed low sensitivity and specificity for skin adnexal origin.

Homeobox transcriptional factor engrailed homeobox 1 is expressed specifically in normal and neoplastic sweat gland cells

AIMS

A number of homeobox transcriptional factors are utilised as organ-specific markers in the histopathological diagnosis of neoplasms. We have screened a homeobox gene that is expressed specifically in normal sweat gland cells and is useful for the histopathological diagnosis of sweat gland neoplasms.

METHODS AND RESULTS

By screening an open database resource of The Human Protein Atlas, 37 genes among the 235 homeobox transcriptional factors were found to be expressed specifically in the skin. Among those 37 genes, the engrailed homeobox 1 (En1) was expressed in normal eccrine glands but not in the epidermal keratinocytes. Expression of En1 was found throughout the eccrine glands, but not in the apocrine secretory coils, sebaceous glands or hair follicles. Expression of En1 was examined immunohistochemically in 111 cases of cutaneous epithelial neoplasms. All nine cases of poroma, seven cases of spiradenoma and six cases of syringoma, which are considered to differentiate towards eccrine glands, showed positive nuclear staining in most of the tumour cells. Sebaceous gland and hair follicle tumours were immunonegative. En1 was expressed focally in the epidermal neoplasms of seborrheic keratosis and squamous cell carcinoma.

CONCLUSION

Engrailed homeobox 1 was expressed specifically in normal eccrine glands and was expressed in most of the tumour cells of sweat gland neoplasms with eccrine gland differentiation. En1 was expressed focally in epidermal neoplasms; however, it was absent in sebaceous or hair follicle neoplasms. These findings will help in the histopathological diagnosis as well as understanding of the histogenesis of sweat gland neoplasms.

Clear cell proliferations of the skin

Clear cell proliferations of the skin consist of a diverse group of lesions characterized by the presence of cells with abundant clear cytoplasm. They may arise from primary, metastatic, or non-neoplastic origins, with their distinctive cytoplasmic clearing attributable to causes ranging from artifact to accumulation of materials such as glycogen, mucin, or lipids. Despite the heterogeneity of these lesions, their distinguishing characteristics may be subtle, especially at high power. As such, histologic diagnosis can be challenging, and proper consideration relies on an understanding of the scope of possible origins, etiologies, and key immunohistochemical staining patterns of the various entities. This review categorizes cutaneous clear cell neoplasms by histogenesis, and offers differential diagnostic strategies to aid in their clinicopathologic evaluation.

Dermal cylindroma of the scalp

Dermal cylindroma is a benign neoplasm of the eccrine sweat glands, which presents in the head and neck area in majority of cases. In its most florid presentation, the entire scalp can be involved, leading to the descriptive label turban tumor. They most commonly occur on the head and neck as solitary or multiple tumors. Solitary cylindromas occur sporadically and typically are not inherited. Multiple tumors are observed in an autosomal dominantly inherited manner. When nodules enlarge and coalesce on the scalp, they form the distinctive turban tumor feature. We present a case of multiple form of dermal cylindroma, occupying the anterior scalp in a 38-year-old male patient.

Cylindroma transforming into basal cell carcinoma in a patient with Brooke-Spiegler syndrome

BACKGROUND

Brooke-Spiegler syndrome is a rare condition with a predisposition to develop cutaneous adnexal neoplasms, especially cylindromas, trichoepitheliomas and spiradenomas. Malignant transformation of cylindromas is rare. In such cases usually cylindrocarcinomas develop within these lesions. We present an unusual case of basal cell carcinoma developing within a preexisting cylindroma.

MAIN OBSERVATIONS

58-year-old woman with a 30-year history of multiple dermal cylindromas extensively involving her scalp was referred for dermatological treatment. The patient reported that one of the long-lasting lesions, 5.5 cm in size, ulcerated within the foregoing few weeks. Histopathology confirmed cylindromas and basal cell carcinoma within the ulcerating tumor. Surgical excision of largest cylindroma tumors led to cosmetic and functional improvement. Magnetic resonance and computed tomography showed tumor infiltration into the skull lamina externa. Metastases were excluded by chest radiography and abdominal ultrasound examination.

CONCLUSION

Patients with Brooke-Spiegler syndrome should be followed-up for malignant transformation of skin tumors to prevent deep penetration and possible metastases.

The expression of CD23 in cutaneous non-lymphoid neoplasms

BACKGROUND

Cluster designation 23 (CD23) is generally used as a lymphoid marker. Its utility in cutaneous epithelial tumors has never been studied. In our routine practice, we observed that CD23 reacted strongly with eccrine and apocrine secretory coils.

METHODS

Immunohistochemical staining of CD23 was performed in a total of 131 cases of apocrine, eccrine, follicular and other cutaneous non-lymphoid tumors.

RESULTS

CD23 expression was detected in all benign apocrine tumors and in half of benign eccrine tumors, particularly those derived from secretory coils. CD23 staining was seen in 42% (8/19) of microcystic adnexal carcinoma (MAC), while no staining was observed in tumor cells of desmoplastic trichoepithelioma, morpheaform basal cell carcinoma and syringoma. All mammary and extramammary Paget's disease were labeled with CD23. In comparison, pagetoid Bowen's disease, melanoma in situ and sebaceous carcinoma exhibited negative staining. In addition, CD23 reacted diffusely with cutaneous mucinous eccrine carcinoma in a manner similar to breast or colonic adenocarcinoma.

CONCLUSION

CD23 appears to be a reliable immunohistochemical marker of the eccrine/apocrine secretory coil and helpful in identifying sweat gland tumors of such origin. It is of ancillary value in differentiating MAC from its mimicker. CD23 is a useful addition to the diagnostic immunohistochemical panels for Paget's disease.

Clear cell papulosis: an immunohistochemical study to determine histogenesis

Clear cell papulosis is a rarely described disease characterized by multiple white maculopapules. Histopathologically, diagnostic clear cells are seen mainly among the basal cells of the epidermis. The origin of the clear cells has been thought to be eccrine or apocrine secretory cells in the epidermis because of the positive immunostaining with anticytokeratin antibody AE1, carcinoembryonic antigen (CEA), epithelial membrane antigen, and gross cystic disease fluid protein-15. IKH-4 and CEA have been reported to stain the eccrine secretory cells, but not the apocrine secretory cells. On the contrary, lysozyme has been reported to stain apocrine glands, but not eccrine glands. CAM5.2 has been reported to show a positive reaction to staining in secretory cells of eccrine glands, but only occasional weak staining in the inner surface of eccrine ducts. In our study, the clear cells in the epidermis stained with IKH-4, CEA and CAM5.2, but not with lysozyme. These results suggest that the clear cells may be eccrine secretory cells.

Spiradenoma arising in a nevus sebaceus of Jadassohn: case report and literature review

Nevus sebaceus (NS) of Jadassohn is usually a verrucous plaque on the scalp or face that arises secondary to disordered development of epithelial, pilar, sebaceous, and apocrine structures. The emergence of neoplasia is a late stage in the natural history of NS. Although most neoplastic proliferations are benign, several malignant tumors have arisen in this lesion. We describe the first case of a benign spiradenoma arising in an NS on the scalp in a 72-year-old Caucasian woman. Reexcision was recommended to prevent the development of a second neoplastic process and to avoid the rare occurrence of a malignant transformation of the existing neoplasia. The patient declined reexcision and remains under observation. The spectrum of tumors arising in NS are described and are categorized according to behavior. Syringocystadenoma papilliferum is the most commonly observed benign growth, whereas basal cell carcinoma is the most frequently seen malignant process. The signs of tumor development (benign or malignant) within an NS are reviewed, and treatment recommendations are provided. The clinical course of rare and unique aggressive neoplasms originating in NS is summarized.