Phase II clinical trial of docetaxel and trastuzumab for HER2-positive advanced extramammary Paget's disease (EMPD-HER2DOC).

BACKGROUND: No consensus has been reached regarding the optimal chemotherapy for metastatic extramammary Paget's disease (EMPD), a rare cutaneous adenocarcinoma, because of the lack of solid evidence from prospective trials. However, the immunohistochemical profile of EMPD reportedly resembles that of breast cancer, particularly in terms of human epidermal growth factor receptor 2 (HER2) expression, suggesting that HER2 is a promising therapeutic target for advanced HER2-positive EMPD. METHODS: In this phase II single-arm trial, 13 Japanese patients received intravenous trastuzumab (loading dose of 8 mg/kg and maintenance dose of 6 mg/kg) and docetaxel (75 mg/m2) every 3 weeks for up to 2 years. The docetaxel dose was reduced or discontinued according to its toxicity. The primary trial endpoints were objective response rate (ORR) after 3 cycles of treatment and safety throughout the study period. RESULTS: All 13 patients completed 3 cycles of combination therapy. The median follow-up was 27.9 months. The ORR was 76.9% (n = 10/13; 90% CI, 50.5-93.4). Frequently observed adverse events were neutropenia (100%), hypoalbuminemia (84.6%), and mucocutaneous infection (84.6%), all of which were well tolerated. CONCLUSION: The combination of docetaxel and trastuzumab demonstrated a favorable clinical effect and acceptable tolerability, which makes it a good treatment option for HER2-positive metastatic EMPD (ClinicalTrials.gov Identifier: UMIN000021311, jRCTs031180073).

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.

Eribulin for patients with metastatic extramammary Paget disease: Study protocol for a single-arm phase II trial.

Extramammary Paget disease (EMPD) is a rare cutaneous malignancy that predominantly affects the anogenital areas of the elderly. Although the efficacy of docetaxel and other cytotoxic agents for advanced EMPD has been reported in small retrospective case studies, no treatment has been proven effective in prospective clinical trials. We established the world's first in vivo EMPD experimental model (a patient-derived xenograft model). In our treatment experiment, xenograft tumours showed a remarkable response to eribulin. This study evaluates the efficacy of eribulin for patients with advanced EMPD. In October 2022, we started a single-arm phase II trial to evaluate the efficacy of eribulin as a treatment for adult patients with unresectable EMPD with measurable lesions. Enrolment in this clinical trial is open to patients with any prior treatment for EMPD. The primary endpoint is overall response rate; the secondary endpoints include disease control rate, overall survival, progression-free survival and adverse events. The study protocol was approved by the Ethics Committee of Hokkaido University and the other collaborating institutions. If the primary endpoint is met, it is our hope that eribulin will be regarded as a standard medication for patients with advanced EMPD.

Extramammary Paget disease. Part II. Evidence-based approach to management.

Extramammary Paget disease is a rare cutaneous malignancy that most commonly affects the genitals, perianal area, and axilla of elderly patients. Delays in care often lead to high levels of disease burden for patients. Thus, evidence-based recommendations are paramount in mitigating morbidity and mortality for this unique patient population. This 2-part continuing medical education series provides a complete picture of extramammary Paget disease. Part 2 of this continuing medical education series focuses on the complex management of extramammary Paget disease including surgical and noninvasive therapies, as well as novel approaches for advanced disease.

Extramammary Paget disease. Part I. epidemiology, pathogenesis, clinical features, and diagnosis.

Extramammary Paget disease (EMPD) is a rare skin cancer of apocrine-rich skin that mimics common inflammatory and infectious dermatoses, leading to delays in diagnosis and increased patient morbidity. Better clinical recognition of this entity, multidisciplinary patient assessment, and deeper understanding of the underlying pathophysiology are essential to improve patient care and disease outcomes. It is important to distinguish primary intraepithelial/micro-invasive EMPD from invasive EMPD or cases with adenocarcinoma arising within EMPD. This 2-part continuing medical education series provides a complete picture of EMPD. Part 1 of this continuing medical education series reviews the epidemiology, oncogenesis, clinical and histopathologic presentation, workup, and prognosis of this rare cancer.

Therapeutic outcomes and survival analysis of Extramammary Paget's disease: A multicentre retrospective study of 249 patients.

BACKGROUND: Evidence regarding long-term therapeutic outcomes and disease-specific survival (DSS) in Extramammary Paget's disease (EMPD) is limited. OBJECTIVES: To assess the DSS and outcomes of surgical and nonsurgical therapeutic modalities in a large cohort of EMPD patients. METHODS: Retrospective chart review of EMPD patients from 20 Spanish tertiary care hospitals. RESULTS: Data on 249 patients with a median follow-up of 60 months were analyzed. The estimated 5-, 10-, and 15-year DSS was 95.9%, 92.9%, and 88.5%, respectively. A significantly lower DSS was observed in patients showing deep dermal invasion (≥1 mm) or metastatic disease (P < .05). A ≥50% reduction in EMPD lesion size was achieved in 100% and 75.3% of patients treated with surgery and topical therapies, respectively. Tumor-free resection margins were obtained in 42.4% of the patients after wide local excision (WLE). The 5-year recurrence-free survival after Mohs micrographic surgery (MMS), WLE with tumor-free margins, WLE with positive margins, radiotherapy, and topical treatments was 63.0%, 51.4%, 20.4%, 30.1%, and 20.8%, respectively. LIMITATIONS: Retrospective design. CONCLUSIONS: EMPD is usually a chronic condition with favorable prognosis. MMS represents the therapeutic alternative with the greatest efficacy for the disease. Recurrence rates in patients with positive margins after WLE are similar to the ones observed in patients treated with topical agents.

Photodynamic application in diagnostic procedures and treatment of non-melanoma skin cancers.

OPINION STATEMENT: Skin tumors commonly seen in dermatology are involved in all layers of the skin and appendages. While biopsy of affected skin remains an essential method to confirm diagnosis and to predicate tumor prognosis, it has its limitations. Recently, photodynamic diagnosis (PDD) has demonstrated high sensitivity in detecting affected skin and mucosal tissues, providing valuable guidance for precision surgery to resect skin and mucosal tumors. In this review, we summarized the literatures concerning the applications of PDD in diagnostic process and treatment of skin and mucosal conditions such as actinic keratoses (AK), basal cell carcinoma (BCC), squamous cell carcinoma (SCC), Bowen's disease (BD) and extramammary Paget's disease (EMPD). The findings suggest that PDD holds substantial promise for expanding clinical applications and deserves further research exploration.

Ultrasonography for the Diagnosis and Follow-Up of Extramammary Paget Disease (EMPD): A Review.

Extramammary Paget disease (EMPD) is a rare skin tumor that manifests as poorly delimited lesions located mainly in genital area. Prognosis correlates with thickness and dermal invasion. The gold standard for diagnosis is the histopathological study of a biopsy. However, this technique is invasive and only shows a small area of the tumor. A good correlation has been reported between ultrasounds (US) and histopathologic finding. Moreover, a US examination has the advantages of wide availability, noninvasiveness, low cost, ease of use, and real-time scanning. We review the ultrasound signs described for this disease.

Extramammary Paget's Disease of the Scrotal and Penile: A Case Report and Review of the Literature.

INTRODUCTION: Extramammary Paget's disease of the scrotum and penis is a relatively rare cutaneous malignant tumor. At present, its pathogenesis, and clinical and pathological characteristics are not very clear. This is controversial regarding surgical margin width to decrease the high recurrence rate. This paper aimed to report the case and review the literature of extramammary Paget's disease of scrotum and penis. CASE PRESENTATION: We presented the case of a 74-year-old male patient with the patchy erythema and pruritus in the perineum who was admitted to our department. Biopsy of the large plaque revealed Paget disease. Under the condition of ensuring negative surgical margins by rapid frozen pathology, a wide local excision of the lesion, bilateral orchiectomy, and adnexectomy were performed on the patient. Pathology revealed that many scattered vacuolated Paget cells were observed in the epidermal layer, and the diagnosis was Paget's disease of the scrotum and penis. The 2 cm outside the skin lesion was used as the initial surgical margin, and free skin flap transplantation was used to repair the surgical wound. The patient recovered well and was discharged 1 week after surgery. CONCLUSION: Currently, histopathologic biopsy is the most important diagnostic method for EMPD. Once confirmed, for patients eligible for surgical intervention, wide local excision of the lesion and rapid intraoperative frozen pathological examination should be performed as soon as possible. The skin flap transplantation is the first choice for the repair of large-scale wound after surgery.

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.

Mohs surgery for female genital Paget's disease: a prospective observational trial.

BACKGROUND: Extramammary Paget's disease recurs often after traditional surgical excision. Margin-controlled surgery improves the recurrence rate for male genital disease but is less studied for female anatomy. OBJECTIVE: This study aimed to compare surgical and oncologic outcomes of margin-controlled surgery vs traditional surgical excision for female genital Paget's disease. STUDY DESIGN: We conducted a prospective observational trial of patients with vulvar or perianal Paget's disease treated with surgical excision guided by Mohs micrographic surgery between 2018 and 2022. The multidisciplinary protocol consisted of office-based scouting biopsies and modified Mohs surgery followed by surgical excision with wound closure under general anesthesia. Modified Mohs surgery cleared peripheral disease margins using a moat technique with cytokeratin 7 staining. Medial disease margins (the clitoris, urethra, vagina, and anus) were assessed using a hybrid of Mohs surgery and intraoperative frozen sections. Surgical and oncologic outcomes were compared with the outcomes of a retrospective cohort of patients who underwent traditional surgical excision. The primary outcome was 3-year recurrence-free survival. RESULTS: Three-year recurrence-free survival was 93.3% for Mohs-guided excision (n=24; 95% confidence interval, 81.5%-100.0%) compared to 65.9% for traditional excision (n=63; 95% confidence interval, 54.2%-80.0%) (P=.04). The maximum diameter of the excisional specimen was similar between groups (median, 11.3 vs 9.5 cm; P=.17), but complex reconstructive procedures were more common with the Mohs-guided approach (66.7% vs 30.2%; P<.01). Peripheral margin clearance was universally achieved with modified Mohs surgery, but positive medial margins were noted in 9 patients. Reasons included intentional organ sparing and poor performance of intraoperative hematoxylin and eosin frozen sections without cytokeratin 7. Grade 3 or higher postoperative complications were rare (0.0% for Mohs-guided excision vs 2.4% for traditional excision; P=.99). CONCLUSION: Margin control with modified Mohs surgery significantly improved short-term recurrence-free survival after surgical excision for female genital Paget's disease. Use on medial anatomic structures (the clitoris, urethra, vagina, and anus) is challenging, and further optimization is needed for margin control in these areas. Mohs-guided surgical excision requires specialized, collaborative care and may be best accomplished at designated referral centers.

Sex differences in initial treatment for genital extramammary Paget disease in the United States: A systematic review.

BACKGROUND: Surgery is the standard treatment for genital extramammary Paget disease (gEMPD). OBJECTIVE: To determine if gEMPD treatments and outcomes differ by sex and US region. METHODS: A systematic review was performed of all English-language studies on initial gEMPD treatment in Medline via PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials.gov. At least 2 reviewers performed title and abstract review and data extraction. Surgical categories included total skinning procedures, partial skinning procedures, Mohs micrographic surgery (MMS), or unspecified surgery. Chi-squared tests of association were used for comparisons. RESULTS: A total of 60 studies comprising 302 (79.7%) female and 77 (20.3%) male patients met criteria. Women were most often initially recommended partial skinning procedures. In all, 74 (24.5%) women and 0 men underwent a total skinning procedure. Men were more likely to be offered MMS than women (40.3% vs 1.9%, P < .0001), despite men having a significantly greater extent of disease involving the perineum and perianal skin (21.1% vs 1.7%, P < .0001). Treatment recommendations varied by US region. LIMITATIONS: Only 20 states were represented. CONCLUSION: Women are more frequently offered total skinning procedures for gEMPD while men are more frequently offered MMS. MMS offers less recurrence and morbidity than total skinning procedures and should be recommended equally to both female and male patients with gEMPD.

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.

Immunohistochemical expression of TRPS1 in mammary Paget disease, extramammary Paget disease, and their close histopathologic mimics.

BACKGROUND: Trichorhinophalangeal syndrome type 1 (TPRS1) expression has been found to be highly sensitive and specific for breast carcinomas. The frequency of TRPS1 expression in cutaneous neoplasms such as mammary Paget disease (MPD) and extramammary PD (EMPD) is currently unknown. We assessed the utility of TRPS1 immunohistochemistry (IHC) in the evaluation of MPD, EMPD, and their histopathologic mimics, squamous cell carcinoma in situ (SCCIS) and melanoma in situ (MIS). METHODS: Twenty-four MPDs, 19 EMPDs, 13 SCCISs, and 9 MISs were subjected to immunohistochemical analysis using anti-TRPS1 antibody. The intensity (none, 0; weak, 1+ ; moderate, 2+ ; strong, 3+ ) and proportion (<1%, absent; 1%-25%, focal; 26%-75%, patchy; >75%, diffuse) of TRPS1 expression were recorded. Relevant clinical data were documented. RESULTS: TPRS1 expression was present in 100% (24/24) of MPDs, with 88% (21/24) of MPDs exhibiting strong, diffuse immunoreactivity. Sixty-eight percent (13/19) of EMPDs showed TRPS1 expression. Intriguingly, EMPDs lacking TRPS1 expression were consistently of perianal origin. TRPS1 expression was seen in 92% (12/13) of SCCISs but was absent in all MISs. CONCLUSIONS: TRPS1 may be useful to distinguish MPDs/EMPDs from MISs, but its utility is limited in distinguishing them from other pagetoid intraepidermal neoplasms such as SCCISs.

A review of 14 cases of perianal Paget's disease: characteristics of anorectal cancer with pagetoid spread.

BACKGROUND: Perianal Paget's disease (PPD) is an intraepithelial invasion of the perianal skin and is frequently associated with underlying anorectal carcinoma. The relatively rare nature of this disease has made it difficult to develop treatment recommendations. This study aims to analyze the clinical and pathological features of perianal Paget's disease (PPD) and to explore rational treatment options and follow-up for this disease. METHODS: The National Cancer Center Hospital database was searched for all cases of perianal Paget's disease diagnosed between 2006 and 2021. In the 14 patients identified, we reviewed the diagnosis, management, and outcomes of adenocarcinoma with pagetoid spread, including suspected or recurrent cases. RESULTS: All 14 cases met the inclusion criteria. The median follow-up period after diagnosis was 4.5 (range, 0.1-13.0) years. Pagetoid spread before initial treatment was suspected in 12 cases (85.7%). Underlying rectal cancer was identified in 6 cases, and no primary tumor was detected in the other 6 cases. Seven patients had recurrent disease, with the median time to recurrence of 34.6 (range, 19.2-81.7) months. The time to the first relapse was 3 months, and that to the second relapse was 6 months. The overall 5-year survival rate was 90.0%. CONCLUSIONS: Endoscopic and radiologic evaluation, as well as immunohistologic examination, should be performed. is to differentiate PPD with and without underlying anorectal carcinoma. The time to first recurrence varies widely, and long-term and regular follow-up for more than 5 years is considered necessary for local recurrence and distant metastasis.

Vulvar pagetoid urothelial intraepithelial neoplasia: a case report.

BACKGROUND: Pagetoid urothelial intraepithelial neoplasia (PUIN) is a form of secondary Extramammary Paget Disease (EMPD). It is a rare malignant condition seen on the female genitalia synchronous or metachronous with bladder cancer (BC). CASE PRESENTATION: A 66-year-old female presented with PUIN at the labia minora 2 years after an open anterior pelvic exenteration with ileal conduit urinary diversion for carcinoma in situ (CIS) of the bladder. PUIN of the vulva and vagina was confirmed by a punch biopsy and the patient underwent a radical vaginectomy with urethrectomy and inguinal sentinel node procedure. Immunohistochemically EMPD was identified by the expression tumor protein 63 (p63), cytokeratin 7, and cytokeratin 20 (CK20). CONCLUSIONS: PUIN is a rare but distinct clinical entity as a form of secondary EMPD which can be differentiated from primary EMPD based on medical history, histology, and immunohistochemistry.

Perianal Paget's disease complicated with lung adenocarcinoma and anal canal carcinoma: A case report and literature review. / 肛周Pagetç— åˆå¹¶è‚ºè ºç™Œå’Œè‚›ç®¡ç™Œ1ä¾‹å¹¶æ–‡çŒ®å¤ä¹ .

Perianal Paget's disease (PPD) is a rare malignant cutaneous tumor. This paper reported a case of PPD complicated by lung adenocarcinoma and anal canal cancer. The patient, a 76-year-old female, had been experiencing recurrent lower abdominal pain and perianal pruritus for the past 5 years. Upon physical examination, a cauliflower-like neoplasm in size of 5 cm×6 cm was observed on the right perianal skin, with local skin ulceration and a small amount of fluid discharge. The left perianal skin was also involved. In thoracoknee position, a hard mass was palpable in the rectal submucosa at 5-6 points 2 cm from the anal verge. Chest CT revealed multiple lesions in both lungs, indication of metastatic tumors. Further evaluation with fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) indicated multiple hypermetabolic nodules in the lungs, hypermetabolic lymph nodes throughout the body, early FDG uptake in a small patch of skin on the left hip, and increased FDG uptake in the anorectal region. Histopathological examination confirmed the diagnosis of lung adenocarcinoma. This resulted in the patient being diagnosed with PPD, lung adenocarcinoma, anal canal cancer, and systemic multiple lymph node metastasis. The combination of PPD with gastrointestinal tumors and other metachronous malignant tumors is highly prevalent. Colonoscopy, FDG-PET/CT, histopathology, and immunohistochemistry play crucial roles in early identification of local lymph node and distant involvement, facilitating the evaluation of potential malignant tumors and differential diagnosis. Treating methods for PPD are currently diverse, including postoperative combined or single chemotherapy, radiotherapy, targeted therapy, and photodynamic therapy. As trerapeutical options continue to develop, the extent and efficacy of surgery need to be reassessed.

Cyclin-dependent kinase 4/6 inhibitors suppress tumor growth in extramammary Paget's disease.

Extramammary Paget's disease (EMPD) is a rare adnexal neoplasm commonly seen in the genital areas among the senior population. The prognosis of advanced EMPD is not favorable; thus, the development of potential treatments has long been sought. Cyclin-dependent kinase (CDK) 4/6 inhibitors such as abemaciclib and palbociclib have been proven effective against metastatic breast cancer; however, no studies have addressed CDK4/6 inhibitors as an EMPD treatment. We herein examine the efficacy of CDK4/6 inhibitors against an EMPD patient-derived xenograft (PDX) model. Abemaciclib (50 mg/kg/day) or palbociclib (120 mg/kg/day) was given orally to tumor-bearing NOD/Scid mice over a 3-week period. We also investigated the protein expression levels of CDK4/6 and cyclin D1 through immunohistochemical staining using EMPD clinical samples. Treatment with abemaciclib or palbociclib as a single agent was found to significantly suppress tumor growth in EMPD-PDX. The Ki-67-positive ratio of the treated EMPD-PDX tumors was significantly lower than that of the nontreated tumors. Clinically, the expression levels of CDK4 and cyclin D1 were significantly higher in the EMPD tumor cells than in the normal epidermis. Our results suggest that CDK4/6 inhibitors could be novel and potent therapeutics for the treatment of EMPD.

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.

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.