Mucosal Invasion, but Not Incomplete Excision, Has Negative Impact on Long-Term Survival in Patients With Extramammary Paget's Disease

Transurethral resection and oral mucosal grafting for urethral-involved extramammary Paget disease: A function-preserving approach

Extramammary Paget disease with urethral involvement presents considerable challenges, primarily because of the difficulty in achieving clear surgical margins while preserving urinary function. This report describes four women with urethral extramammary Paget disease who were treated using transurethral resection followed by oral mucosal grafting for urethral reconstruction. The primary objective was complete excision of the diseased area while minimizing postoperative complications, with a particular focus on preservation of urinary function. Transurethral resection enabled precise resection of the urethral mucosa without compromise of the urethral sphincter. Pathological analysis confirmed negative margins in three of the four patients; one patient had preoperative evidence of tumor cell invasion at the internal urethral orifice. Urinary function was preserved in all patients, and postoperative complications such as urethral stricture were successfully managed using dilation. No recurrences were observed during follow-up. This approach, which combines transurethral resection and oral mucosal grafting, offers a minimally invasive and function-preserving surgical option for urethral-involved extramammary Paget disease, demonstrating favorable oncological and functional outcomes.

A multicenter study on TROP2 as a potential targeted therapy for extramammary Paget disease in Japan

Extramammary Paget disease (EMPD) is a rare skin cancer that typically occurs in the anogenital area of older people. Since efficacy of treatments for metastatic or unresectable EMPD remains poor, development of a novel therapeutic approach is strongly desired. However, the lack of EMPD models has hampered investigation of EMPD. Here we investigated whether trophoblast cell surface antigen 2 (TROP2) could be a promising therapeutic target for EMPD. We retrospectively collected 108 samples from 54 patients with primary and metastatic EMPD from 10 Japanese institutions, and compared TROP2 expression between primary and metastatic lesions of each paired sample. In vitro assays were performed using a newly established EMPD cell line, KS-EMPD-1. TROP2 was strongly and homogeneously expressed in patient tissues, regardless of primary or metastatic lesions. The KS-EMPD-1 cells were treated with a TROP2-targeted antibody-drug conjugate (ADC), sacituzumab govitecan, and it significantly reduced cell viability in a dose-dependent manner compared with that of the cells treated with sacituzumab alone. Knockdown of TROP2 reduced cell viability and cell migration, and caused slight upregulation of the apoptosis-related factors, together with downregulation of the epithelial-to-mesenchymal transition-related factors. These findings suggest that a TROP2-targeted ADC may be a promising treatment option for unresectable EMPD.

Independent Risk Factors for Postoperative Recurrence of Patients with Primary Extramammary Paget's Disease: A Retrospective Analysis

Background

Extramammary Paget's disease (EMPD) is a rare skin cancer with unclear pathogenesis, insidious progression, and high recurrence rate. The purpose of this study was to investigate the clinical features and postoperative recurrence factors of primary EMPD.

Methods

We retrospectively analyzed the medical records of 40 patients with primary EMPD who underwent wide local excision surgery at a single medical center between 2009 and 2019. Risk factors for recurrence of primary EMPD were analyzed using multivariate binary logistic regression.

Results

The study included 40 patients with primary EMPD, comprising 31 males (77.5%) and 9 females (22.5%), with a median age of 75.52 years (range 52-99 years). The most common lesion location was the scrotum (22 cases, 55.0%), followed by the vulva, penis, scrotum, underarm and anus. Multivariable regression analysis revealed significant differences in the presence of ill-defined tumour borders, exudation and nodules in the primary lesion affecting the relapse of primary EMPD (p<0.05).

Conclusion

Our findings indicate that ill-defined tumour borders, exudation and nodules in the primary site should be considered as independent risk factors for disease recurrence, which may provide useful suggestions for the diagnosis, treatment and follow-up of primary EMPD.

NECTIN4-targeted antibody-drug conjugate is a potential therapeutic option for extramammary Paget disease

Extramammary Paget disease (EMPD) is a rare skin cancer mainly found in areas rich in apocrine sweat glands. Since the effective treatments for advanced and/or metastasized EMPD are limited, there is an urgent need to develop novel therapeutic approaches. Nectin cell adhesion molecule 4 (NECTIN4) is highly expressed in cancers and considered to be a promising therapeutic target. NECTIN4 is also expressed in EMPD, but its role and the efficacy of NECTIN4-targeted therapy in EMPD remain unclear. This study investigated the potential of NECTIN4 as a novel therapeutic target for EMPD. NECTIN4 expression was immunohistochemically analysed in EMPD patients' primary (118 samples) and metastatic (21 samples) lesions. Using an EMPD cell line, KS-EMPD-1, the effects of NECTIN4 inhibition on cell proliferation and migration were investigated. NECTIN4 was expressed in primary and metastatic EMPD lesions, and the H-score of NECTIN4 staining was significantly higher in metastatic lesions than in primary ones. Knockdown of NECTIN4 significantly inhibited cell proliferation and affected cell migration. The cytotoxic effects of NECTIN4-targeted antibody-drug conjugate (ADC) were further evaluated, revealing a significant decrease in EMPD cell viability. In conclusion, NECTIN4 is a potential therapeutic target and NECTIN4-targeted ADC is promising as a therapeutic option for EMPD.

FOXM1: a new therapeutic target of extramammary Paget disease

Extramammary Paget disease (EMPD) is a rare skin cancer that primarily affects older individuals predominantly in areas with apocrine sweat glands. Although most early EMPD lesions are indolent, patients with metastatic EMPD have a poor prognosis due to the lack of effective systemic treatment. In this study, we investigated the role of forkhead box M1 (FOXM1), a potent transcription factor, in EMPD and assessed the potential of FOXM1 as a therapeutic target. Immunohistochemistry of 112 primary and 17 metastatic EMPD samples revealed that FOXM1 expression increased with tumor progression. Patients in whom FOXM1 was expressed in more than 10% of tumor cells had significantly shorter disease-specific survival than the other patients (p = 0.0397). In in vitro studies using our newly established EMPD cell line, KS-EMPD-1, we found high expression of FOXM1. Knockdown of FOXM1 impaired tumor cell viability, migration, and invasion. Inhibition of FOXM1 using thiostrepton also reduced tumor cell viability in a dose-dependent manner. These findings suggest that FOXM1 is a promising therapeutic target for patients with EMPD.

Functional preservation benefits of minimal surgery for extramammary Paget's disease

As extramammary Paget's disease (EMPD) sometimes invades and metastasizes from the skin to the mucosa, radical surgical resection of these lesions is often difficult. The purpose of this study was to analyse the association between surgical margins and survival as well as the benefit of functional preservation over complete resection, in patients with EMPD. We retrospectively analysed 230 patients diagnosed with EMPD between 1969 and 2020. Patient and treatment characteristics were recorded. Since our centre is a specialized hospital and almost all patients were referred from other hospitals, we reviewed their referral letters. Prognostic factors and survival time were also analysed. Among 230 patients, 78 (33.9%) had positive margins. The presence of margin positive lesions increased the local recurrence rate but was not significantly correlated with survival. Of all the patients who had received a thorough explanation about the surgical procedure in the referring hospital, 43.8% were scheduled for surgeries that would result in functional impairment, and all of them had function-preserving surgeries at our hospital with a 10-year survival rate of 100%. Our result suggest that less invasive surgery preserves anogenital and urethral function may be an acceptable option for EMPD treatment.

KS-EMPD-1: a novel cell line of primary extramammary Paget's disease

Extramammary Paget's disease (EMPD) is a rare skin cancer that mainly occurs in apocrine sweat gland-rich areas in elderly people. The prognosis of metastatic EMPD is unfavorable because of the lack of fully effective systemic therapies. However, the difficulty in establishing a model of EMPD has hampered basic research for exploring its pathogenesis and optimal treatments. Here, we established for the first time an EMPD cell line (named KS-EMPD-1) from a primary tumor on the left inguinal region of an 86-year-old Japanese male. The cells were successfully maintained for more than 1 year, with a doubling time of 31.2 ± 0.471 h. KS-EMPD-1 exhibited constant growth, spheroid formation, and invasiveness, and was confirmed to be identical to the original tumor by short tandem repeat analyses, whole exome sequencing, and immunohistochemistry (CK7+CK20-GCDFP15+). Western blotting of the cells revealed the protein expression of HER2, NECTIN4, and TROP2, which have recently attracted attention as potential therapeutic targets for EMPD. KS-EMPD-1 was highly sensitive to docetaxel and paclitaxel on chemosensitivity test. The KS-EMPD-1 cell line is a promising resource for basic and preclinical research on EMPD to better define the tumor characteristics and treatment strategy of this rare cancer.

Prognostic Analysis of Patients With Extramammary Paget Disease Treated With Conservative Excision

BACKGROUND

Extramammary Paget disease (EMPD) is a malignant skin tumor with a relatively good prognosis. The standard treatment is wide local resection or Mohs micrographic surgery. However, conservative excision may be a better option when radical wide local excision is difficult to perform due to the patients' mental or physical condition. There have been no studies on the prognosis of patients with EMPD who underwent conservative excision.

OBJECTIVE

To compare the prognosis of conservative excision cases to wide excision cases of EMPD.

MATERIALS AND METHODS

The authors retrospectively analyzed the clinical data of 69 cases of EMPD without metastases to lymph nodes or organs (11 cases treated with conservative excision, 58 cases treated with wide local excision) who underwent resection of the primary tumor from 2002 to 2022 in the Department of Dermatology at Hokkaido University Hospital.

RESULTS

The log-rank test showed no significant differences in overall survival or metastasis-free survival between the wide excision group and the conservative excision group, although conservative surgery was often chosen in elderly patients or patients with lower performance status.

CONCLUSION

This study suggests that conservative surgery should be considered as a treatment option for EMPD.

Current Management and Treatment of Extramammary Paget's Disease

OPINION STATEMENT

Extramammary Paget's disease (EMPD) is a rare neoplastic disease affecting areas rich in apocrine glands in the elderly. EMPD clinically resembles a benign inflammatory skin disease, and ill-defined tumor borders can lead to misdiagnosis and incomplete excision. Several prognostic factors have been reported, including nodule formation, tumor thickness, tumor invasion, lymphovascular invasion, and a perianal location, which are characteristic of primary tumors. EMPD typically presents as an in situ tumor spreading horizontally within the epidermis and then invading into the dermis as it transitions to a vertical growth phase. For this reason, tumor thickness, rather than tumor size, is correlated with patient prognosis. The best treatment for resectable EMPD is complete surgical removal of the tumor. EMPD sometimes has unclear tumor borders, and it can unexpectedly spread beyond its clinical boundaries. Surgical resection in such cases is often associated with tumor-positive margins, which can result in recurrence. However, surgical excision with wide margins may deteriorate patients' organ functions and quality of life. Mohs micrographic surgery may be ideal for controlling the surgical margins and minimizing the sacrifice of normal tissue, but this technique is not always feasible because of constraints associated with the medical environment. No standard treatment for unresectable or metastatic EMPD has been established. Although conventional chemotherapy has been used as the first-line treatment, it frequently causes adverse events, and consequently, targeted therapy will become more valuable in the near future.

CDK4: A Novel Therapeutic Target for Extramammary Paget's Disease

BACKGROUND

The outcome of extramammary Paget's disease (EMPD) is poor when it progresses to metastasis because of the lack of effective systemic therapies. Recently, CDK4-targeted therapy has attracted attention as a potential therapeutic target for some cancers. The aim of this study was to analyze the impact of CDK4 expression on the survival of patients with EMPD.

METHODS

We retrospectively reviewed 110 patients with EMPD. We conducted immunohistochemical analysis of CDK4 and cyclin D1 expression, and assessed the association between their expression and survival.

RESULTS

Most EMPD lesions (108/110, 98.2%) were positive for CDK4 staining and there was a positive correlation between CDK4 expression and cyclin D1 expression (r = 0.54, p < 0.001). Tumor thickness (p = 0.0003) and the presence of regional lymph node metastasis (p = 0.015) were significantly associated with high CDK4 expression. Regarding invasive EMPD, the multivariate analysis did not show the correlation between the expression of CDK4/cyclin D1 and survival outcomes (HR: 3.14, p = 0.14).

CONCLUSION

The overexpression of CDK4 was identified as a major risk factor for disease progression. CDK4-targeted therapy could thus be a novel treatment option for unresectable EMPD.

Trop2 Expression in Extramammary Paget's Disease and Normal Skin

Extramammary Paget's disease (EMPD) is a rare skin cancer arising in the apocrine gland-rich areas. Most EMPD tumors are dormant, but metastatic lesions are associated with poor outcomes owing to the lack of effective systemic therapies. Trophoblast cell surface antigen 2 (Trop2), a surface glycoprotein, has drawn attention as a potential therapeutic target for solid tumors. Sacituzumab govitecan, an antibody-drug conjugate of Trop2, has recently entered clinical use for the treatment of various solid cancers. However, little is known about the role of Trop2 in EMPD. In this study, we immunohistochemically examined Trop2 expression in 116 EMPD tissue samples and 10 normal skin tissues. In normal skin, Trop2 was expressed in the epidermal keratinocytes, inner root sheaths, and infundibulum/isthmus epithelium of hair follicles, eccrine/apocrine glands, and sebaceous glands. Most EMPD tissues exhibited homogeneous and strong Trop2 expression, and high Trop2 expression was significantly associated with worse disease-free survival (p = 0.0343). These results suggest the potential use of Trop2-targeted therapy for EMPD and improve our understanding of the skin-related adverse effects of current Trop2-targeted therapies such as sacituzumab govitecan.