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

Establishment of a trastuzumab-resistant extramammary Paget disease model: loss of PTEN as a potential mechanism

BACKGROUND/OBJECTIVES

Extramammary Paget disease (EMPD) is a rare, cutaneous intraepithelial adenocarcinoma typically treated with wide local excision. Unfortunately, a number of patients with metastases show poor responses to chemotherapy. While some studies have explored trastuzumab's effectiveness against EMPD positive for human epidermal growth factor receptor 2 (HER2), trastuzumab resistance (TR) may emerge after anti-HER2 therapy.

METHODS/SUBJECTS

In this study, we established TR EMPD patient-derived xenografts (PDX) that replicated the histological and HER2 expression traits of naive EMPD tumours.

RESULTS

Cancer gene analyses revealed a loss of the PTEN gene in TR tumours, which was further confirmed by immunohistochemical staining and immunoblotting to test for protein expression levels. Reduced PTEN levels correlated with increased protein kinase B (Akt) phosphorylation and p27 downregulation, suggesting a potential mechanism for trastuzumab resistance in EMPD cells. In the trastuzumab-sensitive EMPD-PDX mouse model, PTEN inhibitors partially restored trastuzumab-mediated tumour regression. The TR EMPD-PDX responded favourably to targeted therapy (lapatinib, abemaciclib, palbociclib) and chemotherapy (eribulin, docetaxel, trastuzumab deruxtecan).

CONCLUSIONS

This study demonstrates an innovative TR EMPD-PDX model and introduces promising antineoplastic effects with various treatments for TR EMPD tumours.

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.

Identification of Predictive Factors for Post-operative Recurrence and Clinical Outcomes of Primary Vulvar Extramammary Paget Disease

BACKGROUND/AIM

Data regarding the clinicopathological factors predicting recurrence and prognosis in patients with vulvar extramammary Paget disease (VPD) are limited. Therefore, we aimed to identify predictive factors for recurrence and outcomes in patients with VPD.

PATIENTS AND METHODS

Forty-five patients with VPD were included in this study. We reviewed electronic medical records and pathology slides to collect clinicopathological information.

RESULTS

Eighteen cases (40.0%) had resection margin (RM) involvement. Twelve patients (26.7%) received adjuvant radiation therapy (RT). Ten patients (22.2%) experienced recurrence. The recurrence rate was higher in patients who underwent wide local excision or simple vulvectomy than in those who underwent radical vulvectomy. Positive RM involvement was a significant and independent predictive factor for worse recurrence-free survival (RFS). The overall survival rate of patients who received adjuvant RT was significantly higher than that of those who underwent surgery alone.

CONCLUSION

A positive RM involvement independently predicted worse RFS. The recurrence rate was significantly associated with the type of surgical procedure performed. Additionally, adjuvant RT can improve the prognosis of patients with VPD.

Vulvar Paget’s Disease: A Systematic Review of the MITO Rare Cancer Group

Vulvar Paget’s disease (VPD) is a rare form of cutaneous adenocarcinoma of the vulva, which accounts for about 1–2% of all vulvar neoplasms and mainly affects post-menopausal women. The clinical presentation is usually non-specific and mimics chronic erythematous skin lesions; therefore, the diagnosis is often difficult and delayed. Although VPD is typically diagnosed at a locally advanced stage and has a high recurrence rate, the prognosis is overall favorable with a 5-year survival of nearly 90%. Due to the limited and poor-quality evidence, there is no global consensus on optimal management. Therefore, we performed a systematic review of the literature through the main electronic databases to deepen the current knowledge of this rare disease and discuss the available treatment strategies. Wide surgical excision is recommended as the standard-of-care treatment and should be tailored to the tumor position/extension and the patient’s performance status. The goal is to completely remove the tumor and achieve clear margins, thus reducing the rate of local recurrences. Non-surgical treatments, such as radiotherapy, chemotherapy, and topical approaches, can be considered, especially in the case of unresectable and recurrent disease. In the absence of clear recommendations, the decision-making process should be individualized, also considering the new emerging molecular targets, such as HER2 and PD-L1, which might pave the way for future targeted therapies. The current review aims to raise awareness of this rare disease and encourage international collaboration to collect larger-scale, high-quality evidence and standardize treatment.

Transcriptomic Heterogeneity of Skin Across Different Anatomic Sites

Multiomic studies, including RNA sequencing, single-cell RNA sequencing, and epigenomics, can provide insight into the connection between anatomically heterogeneous gene expression profile of the skin and dermatoses-predisposed sites, in which RNA sequencing is essential. Therefore, in this study, 159 skin samples collected mainly from discarded normal skin tissue during surgical treatment for benign skin tumors were used for RNA sequencing. On the basis of cluster analysis, the skin was divided into four regions, with each region showing specific physiological characteristics through differentially expressed gene analysis. The results showed that the head and neck region, perineum, and palmoplantar area were closely associated with lipid metabolism, hormone metabolism, blood circulation, and related neural regulation, respectively. Transcription factor enrichment indicated that different regions were associated with the development of adjacent tissues. Specifically, the head and neck region, trunk and extremities, perineum, and palmoplantar area were associated with the central nervous, axial, urogenital, and vascular systems, respectively. The results were imported into an open website (https://dermvis.github.io/) for retrieval. Our transcriptomic data elucidated that human skin exhibits transcriptomic heterogeneity reflecting physiological and developmental variation at different anatomic sites and provided guidance for further studies on skin development and dermatoses predisposed sites.

Cell origin and genome profile difference of penoscrotum invasive extramammary Paget disease compared with its in situ counterpart

Penoscrotum extramammary Paget disease (pEMPD) is a rare cutaneous carcinoma with an unknown cell origin. pEMPD always presents as a tumor in situ with an indolent process, whereas some progress into invasive forms with more aggressive behavior. The in situ and invasive cases display different morphologies and biological behavior, and thus far, a relationship between these two components has not been demonstrated. Immunohistochemistry was used to disclose the immunotype of pEMPD, and the results revealed that invasive/in situ pEMPD possessed with some identical immunophenotypes such as CK7, P63, and CK10, which inferred the clonal relatedness. The variable expressions of GCDFP-15 and carcino embryonic antigen hinted that tumor cell origin might be an epidermal sweat gland in epiderma. In our cohort, invasive pEMPD presented increased expression of androgen receptor and decreased MUC5CA expression, and these two changes might bring to the shift of invasive phenotype. To better understanding the relationship between these distinct tumor forms, we performed whole exome sequencing testing to evaluate overlapping genomic alterations of six paired invasive/in situ pEMPDs. The results showed that missense mutation was the predominant mutation type, and C>T transition accounted for 65.1% in all SNP mutation. Among the top 20 differential genes obtained from the six paired invasive/in situ pEMPD analysis, MUC4 (one missense, one in frame del, and one multi-hit), AHNAK2 (two missense and one multi-hit), DOT1L (two missense and one multi-hit), and FRG1 (two missense and one-multi hit) mutations were most enriched in invasive pEMPDs, which postulated that these genes may play roles in the disease progression.

Case Report: Prolonged clinical benefit with sequential trastuzumab-containing treatments in a patient with advanced extramammary Paget disease of the groin

Extramammary Paget disease (EMPD) is a rare form of cutaneous, intraepithelial adenocarcinoma, which typically presents itself as an erythematous plaque originating from apocrine-gland rich regions, such as the vulva, the perianal region, the scrotum, the penis, or the axilla. EMPD patients typically have a good prognosis, with expected 5-year survival of 60%–92%, but it is estimated that about one-third of EMPD patients will develop lymph node or distant metastases. Treatment approaches for EMPD include locoregional therapies such as broad surgical resection, radiotherapy, or topical imiquimod, when the disease is localized, and chemotherapy and biological agents for advanced EMPD. We report the case of a 58-year-old man diagnosed with locally advanced, symptomatic HER2-overexpressing, AR-positive EMPD, who achieved long-term tumor control with a sequence of several trastuzumab-based treatments (more than 30 months with second-line carboplatin plus paclitaxel plus trastuzumab followed by trastuzumab maintenance; 9 months for third-line vinorelbine plus trastuzumab). Even if it is reported that AR expression occurs concomitantly with HER2 overexpression in more than half of the cases of EMPD, to the best of our knowledge, this is the first case report describing androgen receptor blockade therapy in combination with an anti-HER2 agent. Our patient did not benefit from androgen receptor blockade in combination with trastuzumab, thus suggesting that AR expression may simply reflect an intrinsic characteristic of the EMPD cell of origin, rather than tumor dependence upon AR signaling. Given the reported sensibility to anti-HER2 therapy, also new antibody drug conjugates targeting HER2 are worth exploring in the management of advanced EMPD.

2020 WHO Classification of Female Genital Tumors

The 2020 WHO classification is focused on the distinction between HPV-associated and HPV-independent squamous cell carcinoma of the lower female genital organs. Differentiating according to HPV association does not replace the process of grading; however, the WHO classification does not recommend any specific grading system. VIN are also differentiated according to whether they are HPV(p16)-associated. HPV-independent adenocarcinoma (AC) of the cervix uteri has an unfavorable prognosis. Immunohistochemical p16 expression is considered to be a surrogate marker for HPV association. HPV-associated AC of the cervix uteri is determined using the prognostically relevant Silva pattern.

Successful treatment of a case of hormone receptor-positive metastatic extramammary Paget disease with tamoxifen

Extramammary Paget disease (EMPD) is a rare cutaneous adenocarcinoma that usually is of epidermal origin and shows glandular differentiation and that is treated by wide local excision depending on the disease extent. For widely metastatic disease, however, a standard treatment remains to be established. Similar to breast cancer, EMPD has been found to overexpress human epidermal growth factor receptor 2 (HER2) or hormone receptors (HRs). Whereas HER2-directed therapy was recently shown to be effective for HER2-positive EMPD, the potential role of endocrine therapy for HR-positive EMPD has remained unknown. We here report a case of metastatic EMPD with HR positivity that was successfully treated with the selective estrogen receptor modulator tamoxifen. This first-line treatment of systemic metastasis resulted in durable tumor regression for > 20 months without any treatment-related toxicities. This is the first report to reveal the promise of tamoxifen as a safe and effective treatment for HR-positive metastatic EMPD.