Histological Subtypes

Overexpression of Janus kinase 2 protein in extramammary Paget’s disease

Overexpression of Janus kinase 2 protein in extramammary Paget’s disease

Extramammary Paget’s disease is a rare malignant tumor of the skin that occurs primarily in the genitocrural region. Although the prognosis of extramammary Paget’s disease with distant metastasis is poor, an effective therapy has not been established. Because Janus kinase 2 has attracted attention as a therapeutic target in several cancers, we investigated the expression of the Janus kinase 2 protein and the relationship between its level of expression and clinical significance in 53 patients with extramammary Paget’s disease in our hospital. Immunohistochemistry showed that most extramammary Paget’s disease tissues were positive for Janus kinase 2 (50/53, 94.3%), and the immunostaining intensity of Janus kinase 2 was correlated with the degree of invasiveness, lymph node metastasis and distant metastasis. Based on these findings, Janus kinase 2 may be a promising therapeutic target in extramammary Paget’s disease.

Genito-Urinary Extramammary Pagets disease: Recognition and outcomes of distinct histological subtypes

Genito-Urinary Extramammary Pagets disease: Recognition and outcomes of distinct histological subtypes

Introduction & Objectives: Genito-Urinary Extramammary Pagets Disease (EMPD) is a rare neoplasm that occurs in regions abundant in apocrine glands, or as a secondary intraepithelial spread of EMPD associated with another underlying carcinoma. The former occurs on peno-scrotal skin and can be in-situ or invasive. The latter occurs primarily on the inner precpuce or glans. Management and prognosis differ between these subtypes.

Multicentric Primary Extramammary Paget Disease: A Toker Cell Disorder?

Multicentric Primary Extramammary Paget Disease: A Toker Cell Disorder?

Toker cells are epithelial clear cells found in the areolar and nipple areas of the breast, vulvar region, and other apocrine gland–bearing areas of the skin. Toker cells have been implicated in the pathogenesis of clear cell papulosis, cutaneous hamartoma with pagetoid cells, and rare cases of primary extramammary Paget disease (EMPD) but not in secondary EMPD with underlying adenocarcinoma. The pathogenesis of primary EMPD is not well defined. We report a case of multicentric primary EMPD with evidence of Toker cell proliferation and nonaggressive biologic behavior in a 63-year-old white man. A detailed description of the morphologic and biologic features of Toker cells and their possible carcinogenetic links also are discussed. Based on the observation and follow-up of our patient, we hypothesize that multicentric primary EMPD starts with Toker cell hyperplasia and can potentially evolve to carcinoma in the genital region.

Extramammary Paget disease (EMPD), which was first described by Crocker1 in a patient with erythematous patches on the penis and scrotum, is morphologically identical to mammary Paget disease (MPD) of the nipple. The principal difference between EMPD and MPD is anatomic location.

Depigmented genital extramammary Paget's disease: a possible histogenetic link to Toker's clear cells and clear cell papulosis

Abstract

Background: The histogenesis of extramammary Paget's disease (EMPD) is still controversial. Benign pagetoid cells of the nipple first described by Toker and the similar clear cells found in white maculopapules of clear cell papulosis (CCP) have been proposed to be potential precursor cells giving rise to EMPD and primary intraepidermal Paget's disease in the nipple. The observation of a rare case of depigmented EMPD provided us with a chance to examine further the interesting Toker's clear cell/CCP hypothesis.

Methods: We performed pathologic studies, including Fontana-Masson stain and immunostaining for AE1/AE3 and S100P, on a new case of depigmented EMPD manifesting a 4 x 3 cm hypopigmented-depigmented patch on the root of the penis.

Results: The lesion showed extensive intraepithelial proliferation of atypical pagetoid cells with markedly reduced epidermal melaninization but nearly normal numbers of melanocytes. The tumor cells were strongly positive for AE1/AE3 by immunostaining. Some tumor cells displayed tadpole-like morphology resembling the pagetoid cells of CCP. Such morphology was not observed in two random examples of non-depigmented genital EMPD.

Conclusions: The findings of tadpole-shaped pagetoid cells and depigmentation in the present case suggest that depigmented EMPD may be histogenetically related to CCP. Depigmented EMPD should be considered in the differential diagnosis of vitiligo, depigmented mycosis fungoides and lichen sclerosus located along the milk line.