HER2 oncogene amplification in extramammary Paget's disease

Whole genome sequencing of HER2-positive metastatic extramammary Paget's disease: a case report

BACKGROUND

Extramammary Paget's disease (EMPD) is a rare cancer that occurs within the epithelium of the skin, arising predominantly in areas with high apocrine gland concentration such as the vulva, scrotum, penis and perianal regions. Here, we aim to integrate clinicopathological data with genomic analysis of aggressive, rapidly-progressing de novo metastatic EMPD responding to HER2-directed treatment in combination with other agents, to attain a more comprehensive understanding of the disease landscape.

METHODS

Immunohistochemical staining on the scrotal wall tumor and bone marrow metastasis demonstrated HER2 overexpression. Whole genome sequencing of the tumor and matched blood was performed.

RESULTS

Notable copy number gains (log2FC > 0.9) on chromosomes 7 and 8 were detected (n = 81), with 92.6% of these unique genes specifically located on chromosome 8. Prominent cancer-associated genes include ZNF703, HOOK3, DDHD2, LSM1, NSD3, ADAM9, BRF2, KAT6A and FGFR1. Interestingly, ERBB2 gene did not exhibit high copy number gain (log2FC = 0.4) although 90% of tumor cells stained HER2-positive. Enrichment in pathways associated with transforming growth factor-beta (TGFβ) (FDR = 0.0376, Enrichment Ratio = 8.12) and fibroblast growth factor receptor (FGFR1) signaling (FDR = 0.0082, Enrichment Ratio = 2.3) was detected. Amplicon structure analysis revealed that this was a simple-linear amplification event.

CONCLUSION

Whole genome sequencing revealed the underlying copy number variation landscape in HER2-positive metastatic EMPD. The presence of alternative signalling pathways and genetic variants suggests potential interactions with HER2 signalling, which possibly contributed to the HER2 overexpression and observed response to HER2-directed therapy combined with other agents in a comprehensive treatment regimen.

Extramammary Paget Disease: a Therapeutic Challenge, for a Rare Entity

PURPOSE OF REVIEW

Extramammary Paget disease (EMPD) is a rare entity which is more frequently localized at the vulva, though it only accounts for 1-2% of vulvar neoplasms. It is a primary cutaneous adenocarcinoma whose cell of origin is still a matter of controversy: it can either arise from apocrine/eccrine glands or from stem cells. The diagnosis demands a biopsy and entails a histopathological analysis by which cells show similar characteristics as breast Paget disease.

RECENT FINDINGS

Treatment approach can entail surgery, radiotherapy, photodynamic therapy, systemic chemotherapy, and topical chemotherapy. For metastatic disease, many different chemotherapy regimens have been explored and even targeted therapy can play an important role in this disease. Since almost 30-40% of patients overexpress HER-2, trastuzumab and anti-HER-2 therapies can be employed in this setting. Due to its low incidence, there is almost no specific evidence on therapeutic interventions for this disease. Thus, there is a neat unmet need for molecular characterization of EMPD and diagnostic tools that allow clinicians to guide treatment both in the early and in the advanced disease settings. In this review, we aim to summarize available evidence about diagnosis and treatment of EMPD, both localized and metastatic, and to provide a comprehensive analysis that may help clinicians for therapeutic decisions.

A Positive Dermcidin Expression Is an Unfavorable Prognostic Marker for Extramammary Paget's Disease

Extramammary Paget’s disease is recognized as an apocrine-origin cutaneous tumor and is localized in the intraepithelial skin lesion. However, its advanced form is intractable, and there is currently no therapeutic option with a satisfactory level of clinical outcome. Therefore, it is of great importance to identify a potential biomarker to estimate tumor advancement in extramammary Paget’s disease. Dermcidin is an antimicrobial peptide derived from the eccrine gland and is identified as a biomarker in various malignancies. To investigate the potential of dermcidin in extramammary Paget’s disease, we investigated dermcidin expression in tumors using the immunostaining technique. Although previous studies have reported that extramammary Paget’s disease has no positive staining against dermcidin, 14 out of 60 patients showed positive staining of dermcidin in our study. To clarify the characteristics of positive dermcidin in extramammary Paget’s disease, we investigated the clinical characteristics of positive dermcidin extramammary Paget’s disease patients. Positive dermcidin patients showed a significantly high frequency of lymph node metastasis. We next investigated the impact of positive dermcidin on overall survival. Univariate analysis identified that positive dermcidin showed a significantly increased hazard ratio in overall survival, suggesting that dermcidin might be a prognostic factor for extramammary Paget’s disease.

Hormonal Environment and HER2 Status in Extra-Mammary Paget's Disease (eMPD): A Systematic Literature Review and Meta-Analysis with Clinical Considerations

Background. Extra-mammary Paget’s disease (EMPD) is a rare neoplasm of epithelial origin, whose precise incidence is not clear. Starting from what is already known, we performed a systematic review and meta-analysis to investigate in male and female patients the immunohistochemical expression of biological markers that could serve as potential prognostic/therapeutic factors, including only human epidermal growth factor receptor 2 (HER2/neu), Estrogen Receptor (ER), Progesterone Receptor (PR), and Androgen Receptor (AR). Methods. A literature search was performed of the PubMed, Scopus, and Web of Science databases for English-language studies published from January 2000 to June 2020. Results. A total of 27 studies with 713 patients assessed the role of HER2/neu, AR, ER, and PR expression in male and female with EMPD. The overall rate of HER2/neu expression was 30%, the expression’s rate for ER and AR was 13% and 40%, respectively, and the overall rate for PR was 8%. The subgroup analysis revealed that there is a different expression of molecular markers between male and female patients. Conclusions. This study revealed that AR status and HER2/neu overexpression/amplification have been shown as two fundamental pathogenetic pathways in both female and male patients affected by EMPD.

The Msi1-mTOR pathway drives the pathogenesis of mammary and extramammary Paget's disease

Mammary and extramammary Paget's Diseases (PD) are a malignant skin cancer characterized by the appearance of Paget cells. Although easily diagnosed, its pathogenesis remains unknown. Here, single-cell RNA-sequencing identified distinct cellular states, novel biomarkers, and signaling pathways - including mTOR, associated with extramammary PD. Interestingly, we identified MSI1 ectopic overexpression in basal epithelial cells of human PD skin, and show that Msi1 overexpression in the epidermal basal layer of mice phenocopies human PD at histopathological, single-cell and molecular levels. Using this mouse model, we identified novel biomarkers of Paget-like cells that translated to human Paget cells. Furthermore, single-cell trajectory, RNA velocity and lineage-tracing analyses revealed a putative keratinocyte-to-Paget-like cell conversion, supporting the in situ transformation theory of disease pathogenesis. Mechanistically, the Msi1-mTOR pathway drives keratinocyte-Paget-like cell conversion, and suppression of mTOR signaling with Rapamycin significantly rescued the Paget-like phenotype in Msi1-overexpressing transgenic mice. Topical Rapamycin treatment improved extramammary PD-associated symptoms in humans, suggesting mTOR inhibition as a novel therapeutic treatment in PD.

Extramammary Paget disease of the vulva

Extramammary Paget disease (EMPD) is a rare neoplasm with uncertain histogenesis, usually presenting in the anogenital area, most commonly in the vulva. The disease is characterized by slow grow and high recurrence rates. This article reviews the epidemiological, clinical, morphological, genetic and treatment features of EMPD of the vulva reported in recent years.

Clinical Characteristics, Treatment, and Prognostic Factors of Patients With Primary Extramammary Paget's Disease (EMPD): A Retrospective Analysis of 44 Patients From a Single Center and an Analysis of Data From the Surveillance, Epidemiology, and End Results (SEER) Database

Objective: Primary extramammary Paget's disease (EMPD) is a rare cutaneous malignancy. The aim of this article is to analyze clinical characteristics, evidence of the prognosis, and share treatment experience of primary EMPD.

Methods: We extracted 771 patients' data from the Surveillance, Epidemiology, and End Results (SEER) program between 1973 and 2013 to investigate the characteristics and prognosis of patients with EMPD. In addition, 44 patients with primary EMPD in our hospital were retrospectively reviewed for 10 years.

Results: Compared with patients younger than 65 years, patients diagnosed at 65–74 years [hazard ratio (HR), 2.453] and 75 years or older (HR, 5.750) had shorter survival. Patients with a primary site in the truncal skin (HR, 0.367) or scrotum (HR, 0.246) had better survival compared to those with a primary site in the perianal area. Compared with localized EMPD, EMPD with distant (HR, 18.821) and regional (HR, 2.180) metastases was associated with a worse prognosis. Patients who received radiotherapy had decreased survival, with an HR of 2.039. Patients with a higher N stage, M stage, and American Joint Committee on Cancer (AJCC) stage had a decreased prognosis (p < 0.001).

Conclusions: Older age at diagnosis, primary site in the perianal area, distant metastasis, radiotherapy, and higher N stage, M stage, and AJCC stage may result in decreased survival.

A primer on extramammary Paget's disease for the urologist

Extramammary Paget's disease (EMPD) is a rare and lethal intraepithelial malignancy that remains poorly understood. No standardized guidelines or consensus statements exist with regards to the diagnostic evaluation, therapeutic approaches and follow-up management. Complete surgical excision with negative margins has been accepted as the mainstay of treatment for EMPD to decrease the risk of local recurrence and to maximize durable cure. Non-invasive therapies, such as laser therapy, photodynamic therapy, radiotherapy and topical chemotherapy have been utilized, but are best reserved for non-surgical candidates. While the debate on the surgical approach between wide local excision (WLE) and Mohs micrographic surgery (MMS) continues, several studies have demonstrated the ability of WLE to be performed safely and effectively and to yield equally satisfactory outcomes with similar rates of recurrence to MMS. Patients undergoing surgical excision often require complex closures with skin grafting or local flaps to close genital defects. We aim to provide an up-to-date review of the current knowledge of EMPD. In addition to discussing the clinical presentation and prognostic outcomes, we focus and elaborate on the diagnostic approaches and treatment alternatives available. This information may serve as a primer for the urologist who may be called upon to treat this malignancy primarily or to provide wound coverage secondarily.

Extramammary Paget disease shows differential expression of B7 family members B7-H3, B7-H4, PD-L1, PD-L2 and cancer/testis antigens NY-ESO-1 and MAGE-A

Extramammary Paget disease (EMPD) is a rare cutaneous adenocarcinoma of the anogenital region most commonly treated with surgical excision. Surgical margin clearance is often problematic and recurrence rates remain high indicating the need for additional therapeutic options. Topical immunomodulators have been used with reported success suggesting EMPD may respond to other immunotherapies. This study investigates EMPD protein expression of targetable B7 family members and cancer/testis antigens (CTAs) B7-H3, B7-H4, PD-L1, PD-L2, MAGE-A, and NY-ESO-1 and components of antigen presenting machinery B2M and MHC-I. Fifty-seven specimens from 48 patients (31 female and 17 male), representing in situ, invasive, and metastatic disease of primary and secondary origin were stained and scored (627 total slides). The percentage of cases expressing each immune regulatory molecule in the in situ followed by invasive tumor components was: B7-H3 (94, 90), B7-H4 (82, 78), PD-L1 (6, 10), MAGE-A (39, 50), NY-ESO-1 (16, 20), B2M (100, 89), and MHC-I (78, 79). PD-L2 was negative in all cases. There was high correlation between marker expression within the in situ and invasive tumor components of the same case. B7-H4 was preferentially expressed in primary cutaneous EMPD. Co-expression of B7 family members B7-H3 and B7-H4 was found within the in situ and invasive tumor components of 74% and 48% of cases, respectively. These findings provide an initial characterization of EMPD tumor cell expression of B7-H3, B7-H4, PD-L1, PD-L2, MAGE-A, and NY-ESO-1 and indicate the potential for new immunotherapeutic options for patients with EMPD.

Human epidermal growth factor receptor 2 amplification as a biomarker for treatment in patients with lymph node-metastatic penoscrotal extramammary Paget's disease

The role of human epidermal growth factor receptor 2 (HER2) amplification as a biomarker for treatment in patients with lymph node (LN)-metastatic penoscrotal extramammary Paget's disease (EMPD) was investigated in the present study. A total of 11 male patients with LN-metastatic penoscrotal EMPD were retrospectively reviewed. Positron emission tomography/computed tomography (PET/CT) was conducted prior to surgery. Immunohistochemistry and fluorescence in situ hybridization were used to evaluate HER2 gene amplification in LN samples. Sanger sequencing was used to investigate HER2 mutations. A literature review of the prevalence of HER2 amplification in EMPD and the efficacy of HER2-targeted therapy was also undertaken. PET/CT is effective in detecting metastatic sites. The sensitivity and specificity of PET/CT was 90.9 and 100.0% for inguinal LNs, and 85.7 and 80.0% for pelvic LNs, respectively. The median time from LN dissection to disease progression was 15.9±1.5 months. Of the 11 patients, 3 (27.3%) indicated HER2 amplification. Patients with HER2 amplification showed shorter median times from disease discovery to LN metastasis (HER2 amplification vs HER2 non-amplification; 15.6 vs. 10.0 months; P=0.50) and from LN dissection to disease progression (HER2 amplification vs. HER2 non-amplification, 16.2 vs. 13.6 months; P=0.11). However, the aforementioned observations were not indicated to be statistically significant. No HER2 mutations were identified. Trastuzumab, a HER2-targeted monoclonal antibody, was administered to 2 of the patients with HER2 amplification. A literature review of the prevalence of HER2 amplification in EMPD and the efficacy of HER2-targeted therapy showed similar results. Altogether, 485 cases of EMPD were reported, 35 of which had metastases. The results in the present study suggest that PET/CT should be used on all metastatic EMPD patients. EMPD may be effectively treated with trastuzumab. The present study and case reports from the literature provide evidence for the benefit of testing for HER2 amplification in this rare disease and highlight the requirement for a multicenter clinical trial to assess the impact of trastuzumab therapy in treating this disease.

Metastatic Extramammary Paget's Disease of Scrotum Responds Completely to Single Agent Trastuzumab in a Hemodialysis Patient: Case Report, Molecular Profiling and Brief Review of the Literature

Extramammary Paget's disease (EMPD) is a rare cancer. Although EMPD is usually noninvasive and treated with local therapy, once metastatic the prognosis of EMPD is poor and treatment options are limited. We report a case of a complete response to single agent trastuzumab in a hemodialysis patient with metastatic Her2/neu overexpressed EMPD of the scrotum. Molecular profiling of his case as well as 12 other EMPD and 8 mammary Paget disease (MPD) cases was completed and revealed multiple biomarker aberrations. Overexpression of Her2 was frequently noted (30%-40%) in both EMPD and MPD patients and when present can be effectively treated with Her2 targeted agents. Trastuzumab therapy can be safely utilized in a hemodialysis patient. In addition, multiple protein overexpression and loss were seen in EMPD including PD-1, PD-L1, PTEN, and AR as well as PIK3CA mutation. These findings may lead to possible therapeutic interventions targeting these pathways in a disease with few effective treatment options.

Premalignant lesions of the lower female genital tract: cervix, vagina and vulva

Premalignant lesions of the lower female genital tract encompassing the cervix, vagina and vulva are variably common and many, but by no means all, are related to infection by human papillomavirus (HPV). In this review, pathological aspects of the various premalignant lesions are discussed, mainly concentrating on new developments. The value of ancillary studies, mainly immunohistochemical, is discussed at the appropriate points. In the cervix, the terminology and morphological features of premalignant glandular lesions is covered, as is the distinction between adenocarcinoma in situ (AIS) and early invasive adenocarcinoma, which may be very problematic. A spectrum of benign, premalignant and malignant cervical glandular lesions exhibiting gastric differentiation is emerging with lobular endocervical glandular hyperplasia (LEGH), including so-called atypical LEGH, representing a possible precursor of non HPV-related cervical adenocarcinomas exhibiting gastric differentiation; these include the cytologically bland adenoma malignum and the morphologically malignant gastric type adenocarcinoma. Stratified mucin producing intraepithelial lesion (SMILE) is a premalignant cervical lesion with morphological overlap between cervical intraepithelial neoplasia (CIN) and AIS and which is variably regarded as a form of reserve cell dysplasia or stratified AIS. It is now firmly established that there are two distinct types of vulval intraepithelial neoplasia (VIN) with a different pathogenesis, molecular events, morphological features and risk of progression to squamous carcinoma. These comprise a more common HPV-related usual type VIN (also referred to as classic, undifferentiated, basaloid, warty, Bowenoid type) and a more uncommon differentiated (simplex) type which is non-HPV related and which is sometimes associated with lichen sclerosus. The former has a relatively low risk of progression to HPV-related vulval squamous carcinoma and the latter a high risk of progression to non-HPV related vulval squamous carcinoma. Various aspects of vulval Paget's disease are also discussed.

Paget Cells in Endometrial and Endocervical Curettings in a Patient With Recurrent Vulvar Paget's Disease

INTRODUCTION

Paget's disease of the vulva is a rare malignancy primarily affecting Caucasian women in their seventh to eighth decades. Most patients experience an indolent disease course and undergo surgical excision for disease control. Although progression to invasive adenocarcinoma is rare, recurrence is common because of the difficulty of achieving negative surgical margins.

CASE PRESENTATION

We report a case of a 73-year-old woman with a long-standing history of recurrent vulvar Paget's disease who presented with postmenopausal bleeding. Workup revealed extensive endocervical involvement by Paget's disease, resulting in Paget cells on endocervical curettage, as well as endometrial curettage (because of cervical contamination).

CONCLUSION

Extensive endocervical involvement by vulvar Paget's disease can occur despite multiple reexcisions and topical therapy. The presence of Paget cells on endometrial and endocervical curettings, particularly in patients without visible vulvar or cervical lesions, should raise suspicion of endocervical involvement and prompt further evaluation of disease extension.

Immunohistochemical and fluorescence in situ hybridization studies on noninvasive and invasive extramammary Paget's disease

To determine useful immunohistochemical markers for tumor cells in extramammary Paget's disease (EMPD), immunohistochemical (IHC) examinations in 17 patients with EMPD, including 4 patients with dermal invasion, were performed. Among the antibodies examined, cytokeratin 7 (CK7) and CK19 were strongly positive for both intraepidermal and dermally invasive tumor cells in all patients. CAM5.2 and mucin 1 (MUC1) were also good markers. Although IHC examination revealed positive for HER-2 in 4 EMPD patients with dermal invasion, 4 out of 13 noninvasive patients were IHC negative. Fluorescence in situ hybridization (FISH) study revealed negative results for HER-2 gene amplification in 8 IHC positive patients, including each 4 patients of both noninvasive and dermal invasive cases. Our results show that besides CK7, CK19 is another favorable marker of tumor cells of EMPD. Four patients with dermal invasion were strongly positive for HER-2, although negative results were obtained in the FISH study. Further investigations are required to confirm the results of the FISH study.

A Case of Metastatic Extramammary Paget's Disease Responding to Trastuzumab plus Paclitaxel Combination Therapy

There is no effective treatment for advanced extramammary Paget's disease (EMPD). The human epidermal growth factor receptor 2 (HER2) protein is often overexpressed in EMPD. Trastuzumab is a humanized monoclonal antibody against HER2 used in the treatment of breast cancers in which HER2 is overexpressed. We report a case of advanced EMPD in which trastuzumab and paclitaxel combination therapy was effective. The patient was a 70-year-old Japanese woman who presented with EMPD on the vulva and multiple metastatic lymph nodes. Immunohistochemical staining revealed strong HER2 protein expression in the primary tumor and metastatic lymph nodes. The patient received trastuzumab and paclitaxel. After 4 courses of this regimen, the mass on the vulva and the metastatic lymph nodes regressed. Our findings may imply that trastuzumab plus paclitaxel combination therapy is useful for the treatment of advanced EMPD overexpressing HER2.

Immunohistochemical study of HER2 and TUBB3 proteins in extramammary Paget disease

Metastatic extramammary Paget disease (EMPD) is a potentially fatal malignancy for which effective chemotherapy and good biomarkers are desirable for management. We investigated the status of human epidermal growth factor receptor (HER2) and neuronal β-tubulin isotype (class III β-tubulin; TUBB3), whose overexpression is a factor involved in resistance of tumor cells to taxane derivatives) in 32 patients with EMPD. HER2 status was evaluated by immunohistochemistry followed by fluorescence in situ hybridization, and TUBB3 status was evaluated by immunohistochemistry. On the basis of the US Food and Drug Administration-approved criteria, 20 (63%) of the 32 EMPD tumors were found to overexpress HER2. Positive immunoreactivity for TUBB3 was observed in 7 (22%) of the 32 patients. Although some clinicopathologic variables (nodule formation, depth of tumor cells, presence of lymph node metastasis, and serum carcinoembryonic antigen level) were significantly associated with disease outcome (P < 0.05), HER2 gain or aberrant TUBB3 expression showed no significant correlation. However, the higher incidence of HER2 gain and the relatively lower incidence of aberrant TUBB3 expression suggested that HER2-targeted immunotherapy combined with taxane derivatives is warranted for metastatic EMPD, and that HER2 and TUBB3 status might be a good biomarker for determining the most appropriate therapeutic modality.

Lesions of anogenital mammary-like glands: an update

Long considered to be ectopic breast tissue representing the caudal remnants of the milk ridges, anogenital mammary-like glands are nowadays thought to represent a normal constituent of the anogenital area. Lesions involving these glands, benign or malignant, epithelial or stromal manifest a striking similarity to their mammary counterparts. This review addresses the recent literature on lesions of anogenital mammary-like glands and our personal experience with various lesions related to these structures. Discussed are the normal anatomy and histology of these glands as well as the clinical presentation, histopathological and immunohistochemical features, molecular biological aspects, and differential diagnosis of various lesions involving anogenital mammary-like glands, including lactating adenoma, hidradenoma papilliferum, hidradenocarcinoma papilliferum, fibroadenomas, phyllodes tumor, pseudoangiomatous stromal hyperplasia, extramammary Paget disease, and other carcinomas. In addition, "nonspecific" epithelial or stromal changes some of which can be likened to similar changes occurring in a range of benign breast disease, including sclerosing adenosis, columnar cell lesions, ductal lesions and various metaplastic changes affecting epithelium and myoepithelium are discussed. Although lesions of anogenital mammary-like glands are often discussed in many dermatopathology textbooks in the context of cutaneous adnexal neoplasms we advocate that the best approach to the diagnosis of these lesions is to relate them to analogous well recognized lesions occurring in the breast, that is, through the eyes of a breast pathologist. This will enable their recognition, precise classification and should introduce greater uniformity in how they are reported in the literature so that more meaningful clinicopathological comparisons and correlations may be made.

Frequent expression of the breast differentiation antigen NY-BR-1 in mammary and extramammary Paget's disease

While mammary Paget's disease (MPD) is clearly linked to breast cancer, the histogenesis of extramammary Paget's disease (EMPD) is controversial. Recently NY-BR-1, a differentiation antigen expressed in the breast and in skin adnexal structures was identified. Its protein expression is restricted to normal and neoplastic breast epithelium and to adnexal tumors of the skin. In this study, we examine NY-BR-1 expression by immunohistochemistry in 24 MPD cases with synchronous ductal carcinoma in situ or invasive breast cancer. Results were compared with 26 cases of EMPD of men (n= 4) and women (n= 22) as well as in apoeccrine glands of the axilla and mammary-like glands of the anogenital region. We found NY-BR-1 positivity in 18 of 24 MPD (75%) and in 21 of 26 EMPD (80.8%). All apoeccrine glands of the axilla and mammary-like glands of the anogenital region were NY-BR-1-positive. NY-BR-1 expression is a common finding in MPD and in EMPD. When considering the diagnosis of Paget's disease, NY-BR-1 is a useful diagnostic marker. Furthermore NY-BR-1 positivity in apoeccrine glands of the axilla and anogenital region suggests a potential histogenetic link between these structures and Paget's disease.

Double cancer of plantar malignant melanoma and vulvar extramammary Paget's disease

A 75-year-old woman presented with a 2-year history of a pigmented nodular lesion on her left sole and a 9-year history of a red infiltrative plaque on the vulva. The plantar lesion was a 15-mm ulcerated nodule located at the center of a 25-mm atypical pigmentation region; the nodule was clinically suspected to be a malignant melanoma. Histopathological analysis of the vulvar lesion biopsy sample indicated extramammary Paget's disease (EMPD). There was no evidence of metastasis in the computed tomography (CT) and (18)F-fluorodeoxyglucose positron emission tomography scans. We simultaneously performed a wide excision of both lesions and a left inguinal sentinel lymph node biopsy. Melanoma cells were identified in the sentinel lymph nodes, and left radical lymph node dissection was performed after a course of neoadjuvant chemotherapy. All the lymph nodes that were resected during the second operation tested negative for melanomas, and the plantar lesion was diagnosed as a stage IIIB malignant melanoma (pT4b, Na2, M0). Thereafter, we administrated four courses of chemotherapy, and 8 months after the operation, there was no evidence of recurrence or metastatic lesions. We present a case report of double cancer: a plantar malignant melanoma and vulvar EMPD, and also discuss the possible genetic mutations responsible for these two tumors.

The role of immunohistochemistry in discriminating primary from secondary extramammary Paget disease

BACKGROUND

Extramammary Paget disease (EMPD) is categorized into 2 groups: primary EMPD or EMPD secondary to underlying malignancy. Primary EMPD has a better prognosis, and the ability to distinguish between the 2 subsets has clinical relevance. Recent studies have suggested that immunostains, including cytokeratin (CK) 7, CK20, and BRST-2, distinguish between the 2 groups. We analyzed a large series of EMPD with an expanded immunohistochemical panel to assess its value in distinguishing primary from secondary disease.

DESIGN

Formalin-fixed, paraffin-embedded sections of 98 EMPD specimens from 61 patients (45 primary and 16 secondary) were immunostained with CK7, CK20, HER-2/neu, BRST-2, CDX2, androgen receptor (AR), and cyclin D1. The study included 44 women and 17 men (median age: 73 years). Median follow-up time was 47 months.

RESULTS

All EMPD specimens were vibrantly positive for CK7. The frequency of positivity for all EMPD samples was CK20 (28%), BRST-2 (40%), HER-2/neu (64%), CDX2 (10%), AR (16%), and cyclin D1 (76%). For primary EMPD, the frequency of positivity was CK20 (22%), BRST-2 (48%), HER-2/neu (65%), CDX2 (2%), AR (21%), and cyclin D1 (84%). For secondary EMPD, the frequency of positivity was CK20 (50%), BRST-2 (25%), HER-2/neu (60%), CDX2 (33%), AR (0%), and cyclin D1 (53%). Notably, all 6 of 7 cases of EMPD secondary to an anorectal adenocarcinoma tested were HER-2/neu negative and 5 of those 6 cases (80%) were CDX2 positive.

CONCLUSIONS

The role of CK7, CK20, and BRST-2 in distinguishing primary and secondary EMPD is limited because CK20 and BRST-2 were positive in large subsets of both groups. An expanded immunohistochemical panel, including HER-2/neu and CDX2, may be useful in discriminating primary EMPD from EMPD secondary to anorectal adenocarcinoma but fails to distinguish primary EMPD from EMPD secondary to urothelial or prostatic malignancy. The consistent overexpression of HER-2/neu in primary EMPD suggests a role for trastuzumab therapy in patients with recurrent disease.

HER-2 Gene Amplification in Paget Disease of the Nipple and Extramammary Site: A Chromogenic In Situ Hybridization Study

Patients with human epidermal growth factor receptor 2 (HER-2) overexpressing breast carcinomas have a more aggressive clinical behavior and their tumors are often hormone receptor negative. However, the recently introduced anti-HER-2 antibody trastuzumab has been proven to improve the survival and controls the disease in a significant proportion of these patients. Therefore, the analysis of HER-2 in patients with breast cancer has become an important and routine test to select those who may benefit from the gene-based targeted therapy trastuzumab (herceptin). There is good correlation between HER-2/neu protein overexpression and HER-2 gene amplification in breast cancer. However, inconsistent results have been reported in the rate of HER-2/neu protein overexpression in other malignant neoplasms. Furthermore, only rare studies have investigated the correlation between the HER-2/neu protein overexpression and the status of HER-2 gene in these tumors. We investigated the HER-2 gene and protein status in several cases of Paget disease of the nipple and vulva by using a chromogenic in situ hybridization assay and immunohistochemistry. We find that the majority of the Paget disease of the breast demonstrate HER-2 gene amplification, whereas most of the extramammary Paget disease lack HER-2 gene amplification. In addition, our results show a good correlation between HER-2/neu protein overexpression and HER-2 gene amplification in Paget disease of the nipple, but we were unable to confirm this correlation in HER-2/neu protein overexpressing Paget disease of the vulva.

Potential Diagnostic Utility of CDX-2 Immunophenotyping in Extramammary Paget's Disease

Extramammary Paget's disease (EMPD) is a rare condition whose importance is amplified by its association with either cutaneous or internal malignancy. Recently it has been shown that EMPD is not a single disease but can be divided into cutaneous and endodermal subtypes. The authors studied 12 new cases of immunohistochemically well-characterized EMPD, including HER-2/neu and CDX-2 immunophenotyping. The latter represents a novel application of this nuclear transcription factor, considered to be a relatively specific IHC marker for gastrointestinal-type epithelium. Cutaneous EMPD, accounting for 10 of the 12 (83%) cases, was CDX2-/HER2+; endodermal EMPD, accounting for 2 of the 12 (17%) cases, was CDX2+/HER2-. Four of the 12 cases (33%) were associated with a malignancy (two cutaneous adenocarcinomas, two colorectal carcinomas). The two cases of cutaneous adenocarcinoma occurred in the cutaneous group (2/10 [20%]), while the two cases of rectal carcinoma (one invasive, one in situ) occurred in the endodermal group (2/2 [100%]). Since EMPD subtypes have specific implications with regard to cancer risk, immunophenotyping should be performed in all cases. CDX-2 immunoreactivity may be useful in the subtyping of EMPD.

Gene amplification and protein expression of EGFR and HER2 by chromogenic in situ hybridisation and immunohistochemistry in atypical adenomatous hyperplasia and adenocarcinoma of the lung

AIMS

To investigate the importance of gene amplification and EGFR (epidermal growth factor receptor) and HER2 protein expression during the progression of adenocarcinoma of the lung.

METHODS

EGFR and HER2 gene amplification was examined in atypical adenomatous hyperplasia (AAH), bronchioloalveolar carcinoma (BAC), and adenocarcinoma with mixed subtypes (MX) by chromogenic in situ hybridisation (CISH), and protein expression was examined by immunohistochemistry using paraffin wax embedded tissues.

RESULTS

EGFR and HER2 gene amplification was found in four and two of 86 cases, respectively, and was detected only in the invasive components of MX. EGFR and HER2 protein expression was seen in 24 and 18 of 86 cases, respectively. EGFR and HER2 proteins were not expressed in AAH but were expressed in one BAC case each. EGFR and HER2 proteins were expressed in 23 and 17 of 55 adenocarcinomas with MX. EGFR and HER2 protein expression was seen more often in the invasive components than in the BAC components of MX, and increased significantly as lesions progressed from AAH to BAC, early MX, and overt MX. Because EGFR and HER2 protein expression was frequently seen without gene amplification, other mechanisms apart from gene amplification may be associated with protein expression.

CONCLUSIONS

EGFR and HER2 gene amplification may be a late event and EGFR and HER2 protein expression may be associated with the development of adenocarcinoma of the lung.

Polyomavirus disease in renal transplantation: review of pathological findings and diagnostic methods

Up to 10% of renal transplant recipients can develop polyomavirus nephropathy (PVN) in the allograft, leading to premature graft failure. Recent studies have shown that early diagnosis of PVN before there is irreversible damage to the kidney can result in marked improvement of outcome with resolution of the infection in a large proportion of patients. Early histopathologic diagnosis is complicated by the subtle beginning of the infection and its multifocal nature. This review presents a comprehensive set of guidelines for the effective clinical use of urine cytology and quantitation of viruria and viremia in conjunction with the renal biopsy findings. The morphological features of PVN are presented with specific emphasis on the patterns of PVN that are based on the histological progression of the disease and that correlate with clinical outcome. Also discussed in the context of their clinical significance are the main virological and epidemiological aspects of the BK, JC, and SV40 polyomavirus infections.

Comparative genomic hybridization in extramammary Paget's disease

BACKGROUND

Extramammary Paget's disease (EMPD) is a distinct skin cancer of unknown histogenesis. Data from genome-wide surveys for chromosomal aberrations in EMPD are limited.

OBJECTIVES

To identify chromosomal aberrations that are present in EMPD.

METHODS

Fifteen cases of EMPD were analysed by comparative genomic hybridization (CGH). We used pooled DNA CGH, instead of studying a single sample. In addition, immunohistochemistry was performed for detection of androgen receptor (AR).

RESULTS

The most recurrent change was amplification at chromosomes Xcent-q21 and 19, and loss at 10q24-qter. In addition, expression of AR, located in chromosome X, was found in six cases.

CONCLUSIONS

Results suggest that AR may play a role in EMPD tumorigenesis.

p185HER2 overexpression and HER2 oncogene amplification in recurrent vulvar Paget's disease

We evaluated p186Her2 overexpression and HER2 oncogene amplification in recurrent vulvar Paget's disease. We identified six patients with recurrent vulvar Paget's disease in our archives. The number of recurrences ranged from 1 to 11 over a time period of 1-168 months. Recurrences were evaluated immunohistochemically for p185Her2 overexpression with the HercepTest and for HER2 oncogene amplification with fluorescence in situ hybridization. p185Her2 overexpression was scored as 3 in two patients, as 2 in two patients, and as 1 in two patients. All patients with scores 2 and 3 showed HER2 oncogene amplification. Overexpression of p185Her2 and HER2 oncogene amplification appears to be common in recurrent vulvar Paget's disease.

Matrilysin-1 (MMP-7) and MMP-19 are expressed by Paget's cells in extramammary Paget's disease

BACKGROUND

Extramammary Paget's disease (EMPD) is a rare malignant neoplasm of apocrine gland bearing skin characterized by intraepidermal proliferation of adenocarcinoma cells. Tumor growth depends on the ability of tumor cells to migrate by proteolysis and on angiogenesis. The matrix metalloproteinase (MMP) enzymes have been implicated in both of these processes in other types of skin cancer.

METHODS

The expression of MMP-1, MMP-2, MMP-3, MMP-7, MMP-9, MMP-13, and MMP-19 was analyzed by immuno- histochemistry and/or in situ hybridization in 27 EMPD and five mammary PD (MMPD) specimens. The distribution of laminin-5 (LN-5) and tenascin-C, two extracellular matrix proteins associated with tumor invasion, was studied by immunohistochemistry.

RESULTS

MMP-7 (matrilysin-1) and MMP-19 were the most frequently expressed MMPs in Paget's cells. Overexpression of MMP-2, MMP-9, or MMP-13, which is seen in many cancers, was not evident in EMPD. LN-5 and tenascin-C positivity did not correlate with the level of invasion. MMP-7, MMP-13, and MMP-19 were detected abundantly in MMPD, while MMP-9 was absent.

CONCLUSIONS

MMP expression did not generally associate with the level of invasion of EMPD. In three samples positive for MMP-7 and four samples positive for MMP-19, an underlying carcinoma was detected, suggesting the importance of these two MMPs as predictors of secondary EMPD or the putative origin of Paget's cells from the dermal adenocarcinoma cells of apocrine duct origin.