Initial topical monotherapy may increase the risk of recurrence in patients with extramammary Paget's disease

Treatment of extramammary Paget disease with imiquimod in a real-life setting: a multicentre retrospective analysis in Spain

BACKGROUND

Topical imiquimod has been shown to be an effective treatment for extramammary Paget disease (EMPD), although available evidence supporting its use is based on case reports and small series of patients.

OBJECTIVES

To investigate the therapeutic outcomes and analyse potential clinicopathological factors associated with the imiquimod response in a large cohort of patients with EMPD.

METHODS

Retrospective chart review of 125 patients with EMPD treated with imiquimod at 20 Spanish tertiary-care hospitals.

RESULTS

During the study period, patients received 134 treatment regimens with imiquimod, with 70 (52.2%) treatments achieving a complete response (CR), 41 (30.6%) a partial response and 23 (17.2%) no response. The cumulative CR rates at 24 and 48 weeks of treatment were 46.3% and 71.8%, respectively, without significant differences between first-time and previously treated EMPD. Larger lesions (≥ 6 cm; P = 0.04) and EMPD affecting > 1 anatomical site (P = 0.002) were significantly associated with a worse treatment response. However, the CR rate did not differ significantly by the number of treatment applications (≤ 4 vs. > 4 times per week; P = 0.112). Among patients who achieved CR, 30 of 69 (43%) treatments resulted in local recurrences during a mean follow-up period of 36 months, with an estimated 3- and 5-year recurrence-free survival of 55.7% and 36.4%, respectively.

CONCLUSIONS

Imiquimod appears as an effective therapeutic alternative for both first-line and previously treated EMPD lesions. However, a less favourable therapeutic response could be expected in larger lesions and those affecting > 1 anatomical site. Based on our results, a three to four times weekly regimen of imiquimod with a treatment duration of at least 6 months could be considered an appropriate therapeutic strategy for patients with EMPD.

Network meta-analysis of treatments for perineal extramammary paget's disease: Focusing on performance of recurrence prevention

INTRODUCTION

Perineal extramammary paget's disease (EMPD) is characterized with high recurrence rate. Although numerous therapeutic measures for this disease have been reported so far, it is unknown whether there is significant difference in their recurrence-preventing efficiency. This study aims to compare the recurrence outcomes of reported perineal EMPD treatments.

METHODS

We searched public databases of for published studies concerning perineal EMPD treatments. After screening by inclusion and exclusion criteria, we extracted the data relevant to recurrence rate, and conducted network meta-analysis (NMA) by using Bayesian random-effects approach.

RESULTS

Our analysis included 29 previous studies (involving both male and female patients) and 11 treatment designs which are wide local excision (WLE), local excision (LE), Mohs micrographic surgery (MMS), radiotherapy (RT), radical vulvectomy (RV), photodynamic therapy (PDT), lasers (LS), imiquimod, and WLE+RT, WLE+PDT, WLE+LS. Comparing with WLE, the MMS showed significant advantage in reducing recurrence [OR: 0.18 (0.03-0.87)], while none of the rest treatments has statistically significant results. After removing outlier studies, MMS still has the significant advantages [OR: 0.35 (0.11-0.82)], and LE turned to be the treatment with worst performance [OR: 13 (2.50-110)]. Covariance analysis of follow-up length, gender differences, and lesion locations indicated only short follow-up time could affect the recurrence statistics, which tend to conceal the real differences. Funnel plot demonstrated there is no significant small study effect.

CONCLUSION

MMS has the best performance on reducing perineal EMPD recurrence, while LE exhibits the worst capability in such regard. Recurrence-preventing abilities of other treatments have no significant difference between each other.

Extramammary Paget's Disease: Diagnosis, Pathogenesis, and Treatment with Focus on Recent Developments

Extramammary Paget's disease (EMPD) is a rare neoplasm that usually develops in apocrine gland-bearing areas, such as the vulva, scrotum, and penis. EMPD may present with a focal, multifocal, or an ectopic lesion. Clinically, EMPD lesions often exhibit infiltrative erythema, which is sometimes similar to other skin disorders such as eczema. While primary EMPD arises as intraepithelial neoplasm of the epidermis, EMPD-like lesions may occur from epidermotropic spread of malignant cells or direct extension from an underlying internal neoplasm, known as secondary EMPD. Because treatment strategies differ for primary EMPD and secondary EMPD, accurate diagnosis based on detailed histopathological evaluation is required. In the early stages, EMPD usually shows indolent growth, and most cases are diagnosed as carcinoma in situ. However, invasive lesions may result in metastases, and deep invasion is associated with high incidence of metastases. Conventional chemotherapies have been used for EMPD treatment in patients with distant metastases, but the efficacy is not satisfactory, and the prognosis for such patients remains poor. Recent studies have provided various insights into the molecular pathogenesis of the development and advancement of EMPD, which may lead to novel treatment approaches for metastatic EMPD. This review addresses the diagnosis, pathogenesis, and treatment of EMPD with focus on recent progress in understanding this disease.