Extramammary Paget's Disease Lesions Research Articles

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

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. To investigate the therapeutic outcomes and analyse potential clinicopathological factors associated with the imiquimod response in a large cohort of patients with EMPD. Retrospective chart review of 125 patients with EMPD treated with imiquimod at 20 Spanish tertiary-care hospitals. 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. 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.

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.

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

Evidence regarding long-term therapeutic outcomes and disease-specific survival (DSS) in Extramammary Paget's disease (EMPD) is limited. To assess the DSS and outcomes of surgical and nonsurgical therapeutic modalities in a large cohort of EMPD patients. Retrospective chart review of EMPD patients from 20 Spanish tertiary care hospitals. Data on 249 patients with a median follow-up of 60months 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 (≥1mm) 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. Retrospective design. 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.

Clinicopathological significance of androgen receptor expression in extramammary Paget disease: An analysis of 92 patients

Extramammary Paget disease (EMPD) is a rare cutaneous malignant neoplasm arising in apocrine gland-rich areas. Although – like normal apocrine glands – EMPD frequently expresses androgen receptor (AR), the clinical significance of AR expression remains unclear. The present study investigated the clinicopathological impact of AR expression in EMPD. Immunohistochemistry for AR was performed in a retrospective cohort of 92 EMPD patients with 108 EMPD lesions, including 102 primary lesions, five lymph node [LN] metastases and one local recurrence. The total AR staining score was calculated as staining intensity score (IS 0–3) × positive-cell percentage score (PS 1–4). Expression levels were graded as Grade 1 (scores 0 and 1), Grade 2 (scores 2–4), and Grade 3 (scores 6–12). Higher expression grade was correlated with tumor thickness (P = 0.011), LN metastasis (P = 0.008), and higher EMPD stage (P = 0.023). Grade 1 EMPDs did not invade into the dermis and did not generate metastatic and/or recurrent lesions, whereas only Grade 2 or 3 EMPDs did so. AR expression in invasive components was significantly higher (P = 0.023) than in non-invasive components remaining within the epidermis. AR expression was further elevated in metastatic and/or recurrent lesions relative to locally invasive lesions (P = 0.014). These results clearly indicate that increased AR expression is associated with malignant progression of EMPD and that androgen blockade might be an effective therapy. Furthermore, AR expression assessed by immunohistochemistry may have potential for prediction of LN metastasis and local recurrence in EMPD.

Immunohistochemical and clinicopathological study regarding nardilysin on extramammary Paget's disease.

It has been reported that nardilysin (NRDC), a metalloendopeptidase which regulates various growth factors and cytokines, is associated with malignancies in a conflicting manner, in which it promoted gastric, hepatocellular, and colorectal cancers and suppressed pancreatic ductal adenocarcinoma. However, it has not been investigated how NRDC is associated with cutaneous malignancies for now. Immunohistochemical staining has revealed that NRDC expression is observed in all extramammary Paget's disease (EMPD) cases. Notably, other cutaneous malignancies including basal cell carcinoma, squamous cell carcinoma, and eccrine porocarcinoma, did not show increased NRDC expression in immunohistochemistry. EMPD typically presents several types of lesions including nodules, and positive staining of NRDC on EMPD was observed regardless of the type of lesions. Examination using samples taken from nodular lesions showed that some cases showed heterogenous NRDC expression within each lesion. We also found that NRDC staining was weaker in the marginal parts of EMPD lesion than in the central parts in several cases, and tumor cells tend to be distributed beyond the macroscopic skin lesions in these cases. It was speculated that decreased NRDC expression in the marginal zones of the skin lesions may be associated with the ability of tumor cells to produce the cutaneous manifestation of EMPD. This study suggests that NRDC may be associated with EMPD like other malignancies reported previously.

Value of pseudopod sign on high‐frequency ultrasound in predicting the pathological invasion of extramammary Paget's disease lesions

Vertical invasion of extramammary Paget's disease (EMPD) is associated with poor prognosis. The usual vertical invasion route is directly downward or along the skin appendages. High-frequency ultrasound (HFUS) can be used to measure the EMPD lesion thickness, and visualize the pseudopod extensions due to skin appendage involvement. It is a non-invasive method for evaluating the extent of vertical invasion in EMPD. To investigate the value of HFUS in predicting the extent of vertical invasion in EMPD. In this retrospective study, 85 patients with EMPD were divided into two groups based on the pathology: invasive EMPD (iEMPD) group (n = 13) and in situ EMPD group (n = 72). The clinical and HFUS features of both the groups were analysed. The different types of pseudopodia morphology on HFUS were as follows: no pseudopodia, irregular bottom, small sphere, short strip, long strip, vase shape and nodular convex. These were further stratified into low-risk and high-risk levels. The clinical features were comparable between the two groups (P > 0.05). There were significant differences between the two groups in the HFUS features (lesion thickness, lesion shape, bottom shape, layer involvement, pseudopodia morphology and colour Doppler blood flow signal; all P < 0.05). The distribution of the pseudopodia morphology types in the in situ EMPD and iEMPD groups was as follows: no pseudopodia, 30/72 and 0/13; irregular bottom, 5/72 and 0/13; small sphere, 5/72 and 0/13; short strip, 21/72 and 0/13; long strip, 8/72 and 3/13; vase shape, 3/72 and 3/13; and nodular convex, 0/72 and 7/13 (P < 0.05 for all). The sensitivity and specificity of high-risk pseudopodia in identifying iEMPD were 100% and 84.7%, respectively. High-frequency ultrasound provides morphological information regarding EMPD lesions. Risk stratification for pseudopodia can help to distinguish between iEMPD and in situ EMPD lesions.

Evaluation of in vivo reflectance confocal microscopy in the diagnosis of extramammary Paget's disease.

Extramammary Paget's disease (EMPD) is a rare cutaneous malignancy that most commonly affects the apocrine glands of older men and women. Because it is associated with other cancers, early diagnosis and evaluation are needed. This study is to evaluate the value of reflectance confocal microscopy (RCM) in diagnosing EMPD. A total of 73 patients with clinically suspicious diagnosis of EMPD were enrolled in this study, and the RCM device imaged their lesions. Moreover, 67 patients underwent skin biopsies to confirm the diagnosis. We retrospectively analyzed the results of RCM and histological diagnosis and then evaluated the RCM value of biopsy-confirmed lesions. Based on the RCM image analysis, 54 of 73 (74.0%) patients were diagnosed with EMPD. Of all 67 biopsied lesions, 52 (77.6%) were EMPD. Then, we analyzed the RCM characteristics of 52 cases of biopsy-confirmed EMPD, compared their RCM image characteristics of three different lesions of EMPD, and further concluded the key points of EMPD under RCM microscopy based on the 52 EMPD cases. Finally, we focused on the differential diagnosis of EMPD from other skin diseases. RCM showed great diagnostic value in diagnosing EMPD.

Outcomes of mohs microgrpahic resection for cutaneous malignancy involving the scrotum

IntroductionSquamous cell carcinoma (SCC) and extramammary Paget's Disease (EMPD) of the scrotum are exceedingly rare. Given their propensity for local invasion and treatment with wide local excision, they can be highly morbid conditions. Outcomes of Mohs Micrographic Surgery (MMS) for scrotal cutaneous malignancy is not well described in current literature. We hypothesized that MMS for scrotal cutaneous malignancy would provide equivalent or improved oncologic outcomes while limiting the morbidity associated with wide excision. Materials/MethodsThis is a retrospective review and analysis of a prospectively maintained database spanning entries from 2005 to 2019. Collected data included general patient characteristics and surgical characteristics reported on a per lesion basis. MMS was performed by our institution's department of dermatology using their standard technique. ResultsOverall, a total of 26 consecutive patients with 28 lesions (SCC or EMPD) were analyzed. Out of our cohort of 15 patients with 16 scrotal SCC lesions, 10 (66%) patients were current or former smokers, 4 (26%) were immunosuppressed, and 2 (13%) had HPV infections. The median preoperative and postoperative size of SCC lesions were 5.7cm [2] and 20.2cm [2] respectively. There was one (6%) oncologic recurrence of SCC of the scrotum and one (6%) local wound complication. Our cohort also included 11 patients with 12 scrotal EMPD lesions. One patient (9%) had an underlying associated malignancy (prostate cancer). The preoperative and postoperative area of lesions were 50.6cm [2] and 96.4cm [2] respectively. One (9%) EMPD lesion had a positive final margin at resection requiring reoperation. After achieving negative surgical margins, no patients in this cohort had an oncologic recurrence. 3 (26%) scrotal EMPD cases had local wound postoperative complications, only one required reoperation. ConclusionTo our knowledge, this is the first case series focused on MMS for both SCC and EMPD with scrotal involvement. Our data suggests that MMS for scrotal cutaneous malignancy may improve oncologic outcomes and may decreases local post-operative reconstructive issues when compared to reported outcomes of treatment with wide local excision. When able, scrotal cutaneous malignancy patients should be referred to urologists at centers with MMS capabilities as it likely will improve their outcomes. The urologist should maintain active involvement with these patients to coordinate this complex and advanced pattern of care.

Treatment of Extramammary Paget Disease and the Role of Reflectance Confocal Microscopy: A Prospective Study.

Extramammary Paget disease (EMPD) poses treatment challenges. Invasive and noninvasive treatment modalities exist with variable success reported. Reflectance confocal microscopy (RCM) is emerging as an adjuvant diagnostic tool. To evaluate the treatment of EMPD patients and the role of RCM. Prospective study. Demographic and tumor characteristics were recorded. Handheld-RCM was performed and correlated with histology. Treatment, clearance, pathology, and follow-up were all recorded. Thirty-six EMPD lesions in 33 patients were included. Mean age was 71.7 years, and 23 were men. Mean number of surgical stages needed to clear margins was 1.9 (SD, 0.9; 1.0-3.0 stages), and mean margin needed to clear was 1.8 cm. Reflectance confocal microscopy correlated well with scouting punch biopsies (kappa, 0.93; p < .001). Disruption of the dermoepidermal junction was associated with invasive EMPD versus in situ (83.3% vs 25.9%) on histology (p = .01). Relatively small sample size. Extramammary Paget disease is challenging, and lesion demarcation is of the utmost importance. Using a staged surgical excision approach, the mean margins needed were 1.8 cm, less than previously reported. Nonsurgical modalities, including radiation therapy, imiquimod, or photodynamic therapy can be considered if surgery is not pursued. Reflectance confocal microscopy is a valuable noninvasive imaging modality for the management of EMPD.

Clearance of an extramammary Paget's disease lesion with latex of milkweed (Euphorbia peplus), the raw material of ingenol mebutate.

Clearance of an extramammary Paget's disease lesion with latex of milkweed (Euphorbia peplus), the raw material of ingenol mebutate.

Androgen receptor, androgen-producing enzymes and their transcription factors in extramammary Paget disease

Extramammary Paget disease (EMPD) has been known to frequently express androgen receptor (AR). Therefore, androgens could play roles in the biological behavior of Paget cells. 5α-Reductase (5α-red) types 1 and 2 and 17β-hydroxysteroid dehydrogenase type 5 (17β-HSD5) are pivotal in situ regulators of androgen production in androgen-responsive tissues including androgen-dependent neoplasms. Therefore, in this study, we immunolocalized AR, androgen-producing enzymes, and their transcription factors to assess the state of in situ androgen production and actions and its correlation of invasiveness in EMPD. We studied 51 cases of EMPD with known clinicopathological status. AR, 5α-red1, 17β-HSD5, and β-catenin immunoreactivity was evaluated by using the modified H-score method while cyclin D1, p53, forkhead box protein P1, and a proliferation marker, Ki-67, were quantified using labeling index. The mean scores of AR, 5α-red1, and 17β-HSD5 in invasive EMPD were all significantly higher than noninvasive EMPD (P < .0001). Ki-67 labeling index as well as the cyclin D1 score was also significantly higher in invasive than noninvasive lesions of EMPD. These results demonstrated that androgen receptor and androgen-producing enzymes were both associated with cell cycle regulation and subsequently the invasiveness of EMPD lesions and could also indicate those above as potential markers of invasive potentials in EMPD.

A Case of Extramammary Paget's Disease Resistant to Photodynamic Therapy and Surgery Successfully Treated with Radiotherapy.

Dear Editor: Although surgery is widely accepted as the first-line treatment for extramammary Paget's disease (EMPD), it cannot always be accomplished due to its frequent involvement of areas with important function1. Nonsurgical treatments including radiotherapy (RTx) and photodynamic therapy (PDT) are considered in such cases. We report a case of EMPD refractory to PDT and surgery that was successfully treated with RTx. A 68-year-old man presented with a well-defined erythematous patch with ulceration on the left side of scrotum, which enlarged during the last 7 months (Fig. 1A). Skin biopsy revealed numerous Paget cells (Fig. 2). Possible accompanying internal neoplasms were discounted through multiple means, ranging from physical examination to positron emission tomography/computed tomography. Diagnosed as localized EMPD, the patient was primarily treated with PDT because he strongly requested preservation of his genitourinary functions. Methyl aminolevulinate cream (Metvix; Galderma, Fortworth, TX, USA) was applied occlusively and was maintained for 3 h. The lesion was then irradiated with a 630-nm light-emitting diode (Aktilite CL128; Photocure, Oslo, Norway). After two sessions, the patient showed a partial response and underwent local excision. He was treated with 15 sessions of PDT for possible remnants. As Paget cells were still seen on follow-up biopsy of the surgical margin, he underwent a three-stage Mohs surgery and received 11 additional sessions of PDT. Nonetheless, the lesion persisted clinically. We referred him to the radiation-oncology clinic. Radiation was administered by using an electron beam of 6 MeV, at 200~250 cGy per day, 4 days a week, until a total dose of 37 Gy was reached. He received subsequent RTx with a total dose of 30 Gy in same manner. The lesion disappeared completely. After 18 months, the patient revisited our clinic with an erythematous patch on the scrotum (Fig. 1B). Biopsy only revealed telangiectatic dermal vessels. Fig. 1 (A) Patient image at initial visit. (B) The patient revisited our clinic suspecting of recurrence. The biopsy of skin lesion did not show any tumor cells. Fig. 2 Skin biopsy showing acanthotic epidermis with numerous Paget cells of large nucleus and eosinophilic cytoplasm (H&E, ×200). A systematic review of clinical studies examining the use of PDT for EMPD showed that of 133 EMPD lesions, 77 exhibited complete response and 52 exhibited partial response with satisfactory cosmetic outcome in all patients2. However, the durability of this response remains unclear, as the follow-up periods were typically less than a year2. In a long-term follow-up study of EMPD in situ for 24 months, the recurrence rate was 50%. The authors stated that PDT should be recommended only for cases of scrotal lesions <4 cm in diameter3. Larger lesions showed an unfavorable response presumably because of the denser infiltration of Paget cells and more adnexal involvement, followed by disproportionate protoporphyrin IX accumulation in the glands resulting in photodynamic oxygen depletion. In the present case, the lesion was much larger than 4 cm, which may have been responsible for the ineffectiveness of PDT. The optimal RTx dose is not standardized; however, a total of 40~50 Gy has been considered suitable for primary treatment4. The lesion of our case was refractory to other therapies; hence, a higher dose of 67 Gy was chosen. In conclusion, EMPD lesions resistant to PDT and surgery may be significantly resolved with RTx; thus, it should be considered a treatment option in cases of repeatedly unsuccessful PDT and surgery.

Tumor thickness as a prognostic factor in extramammary Paget's disease.

Extramammary Paget's disease (EMPD) is a rare tumor and a widely accepted classification system specific for the disease has not been established. To elucidate prognostic factors of EMPD, we conducted a retrospective review of 145 patients with 155 EMPD lesions and investigated clinicopathological factors using univariate and multivariate analyses. We also explored tumor thickness and metastatic lymph nodes using detection analysis to determine cut-off points for survival. All patients were Japanese (88 men and 57 women), with EMPD in the genital (82.8%), perianal (3.4%) and axillary regions (1.4%). In the remaining cases (12.4%), there were lesions at two or more regions. Univariate analysis revealed the following prognostic factors: perianal location, presence of nodules, invasion depth, tumor thickness, number of metastatic nodes and serum carcinoembryonic antigen level. Both tumor thickness and perianal location retained statistical significance in multivariate analysis (hazard ratio, 1.39; 95% confidence interval, 1.12-1.72; P = 0.0024; hazard ratio, 50.72; 95% confidence interval, 4.20-612.63; P = 0.0020; respectively). The signal detection analysis indicated tumor thickness of more than 3 mm and three or more metastatic lymph nodes as cut-off points for survival. In conclusion, tumor thickness and the number of metastatic lymph nodes closely correlated with patient outcome and these factors could be suitable for the tumor and node classification.

A prospective pilot study to evaluate combined topical photodynamic therapy and surgery for extramammary paget's disease

Extramammary Paget's disease (EMPD) is a rare intra-epithelial neoplasm. Surgical excision is the treatment of choice. The usefulness of topical photodynamic therapy (PDT) in the treatment of EMPD has been reported. The objective of this prospective pilot study was to investigate the feasibility of combined PDT and surgery in the treatment of EMPD. A total of 13 patients with 19 large EMPD lesions were recruited and assigned to surgery (n = 5) or PDT + surgery (n = 8) group. For the PDT + surgery group, four sessions of topical PDT mediated with 20% 5-aminolevulinic acid (ALA-PDT) were applied prior to surgery. Patients were followed up for 12 months. Treatment outcomes, adverse reactions and recurrence were compared. In the surgery group, recurrence was seen in 2 out of 8 lesions (25%). In the combination group, over 58% reduction in lesion size was achieved after 4-sessions of PDT and recurrence was seen in 1 out of 11 lesions (9.1%) after surgery. Multiple ALA-PDT could be applied to reduce the severity of EMPD lesion and improve the success of surgery.

MUC5AC expression correlates with invasiveness and progression of extramammary Paget's disease

Patients with in situ extramammary Paget's disease (EMPD) tend to have a good prognosis, although dermal invasion and metastasis are associated with significantly increased morbidity and mortality. Previous studies have addressed mechanisms underlying the EMPD pathogenesis; however, no molecular markers that reflect invasiveness or progression have been established. This study aims to identify a reliable marker for predicting the risk of invasion and metastasis in EMPD. We performed an initial microarray screening for in situ, invasive or metastatic lymph node lesions of EMPD. We analysed 44 specimens from 38 primary EMPD cases by immunohistochemical staining. We found that expressions of MUC5AC directly correlate with invasion and prognosis. Labelling rates of tumour cells were scored by staining intensity on a four-tiered scale (- to 3+) to investigate the correlation between the expression score of these molecular markers and the type of EMPD lesion. All the specimens scored positive (3+) for MUC1 and negative (-) for MUC6. MUC5AC expression was detected in 19 of 44 (43.2%) specimens. Invasive lesions and metastatic lymph nodes tended to express MUC5AC significantly higher than in situ lesions (P < 0.01). MUC2 was positive in 10 specimens (22.7%). There was no significant difference between the degree of MUC2 expression and invasiveness. The degree of MUC5AC expression may correlate with the invasiveness and progression of EMPD, and may be a useful marker for identifying high-risk EMPD cases.

Induction of Vitiligo-Like Hypopigmentation after Imiquimod Treatment of Extramammary Paget's Disease

Dear Editor: Imiquimod 5% cream, an immune response modifier, is licensed for the treatment of extramammary Paget's disea se (EMPD). Although pigmentary changes associated with imiquimod treatment have been listed as possible side effects on the package insert, the reports are rare and sometimes inconsistent in the dermatology literature. Some studies described vitiligo-like hypopigmentation, while other studies reported hyperpigmentation after imiquimod use1. In our skin cancer clinic, we frequently applied imiquimod 5% cream every other night for 6~8 hours in EMPD patients who are poor surgical candidates or susceptible to local recurrence after surgery. After reviewing the clinical course of three male patients with EMPD, we found that whole skin lesions around scrotum applied with imiquimod were completely depigmented after 3 months in all cases (Fig. 1). The depigmentation did not extend beyond treatment area and affect other vitiligo-prone areas at all. Despite discontinuation of imiquimod, the hypopigmentation did not improve at all after at least 13 months follow-up in all cases. Imiquimod was the only product used and our patients did not have a history of vitiligo at all. Wood light examination shows an accentuation of the pigment loss, and H&E and Fontana Masson reveal decreased pigmentation in the basal layer of epidermis (Fig. 2). The average number of melanocytes in the basal layer counted by 3,4-dihydroxyphenylalanine staining and immunohistochemistry method using HMB-45 antibody was also significantly decreased (Fig. 3). Interestingly, two of our patients had experienced irritiation several times after cryotherapy and podophylline application before imiquimod treatment without inducing any depigmentation, respectively. This supports the likelihood that imiquimod may have caused the vitiligo-like hypopigmentation by a mechanism other than simple irritation. Several possible mechanisms could explain this hypopigmentation. Imiquimod binds to the Toll-like receptors (TLR) 7 and 8 which are cell-surface receptors recognizing ligands associated with pathogenic organisms. TLR-7 activates the T-helper (Th) 1 response and increases the production of pro-inflammatory cytokines mainly interferon-α, tumor necrosis factor-α and interleukin (IL)-12, all of which play a role in the pathogenesis of vitiligo2. The stimulation of the Th1 pathway also results in a predominantly perilesional CD4+ T cell infiltrate and many CD8+ T cells. The CD4+ cells are stimulated by IL-12 to produce IFN-α and IL-2. In addition, imiquimod promotes secretion of IL-6, IL-8, and IL-10, which are pro-inflammatory and pro-apoptosis cytokines that can also cause vitiligo3,4. A previous case report stated that a trial with macrolide immunomodulators could benefit patients, although lacking sufficient evidence5. Expanded use of imiquimod may increase localized depigmentation as observed in our case. Since patients could be emotionally sensitive to the depigmentation of pubic areas, we believe that dermatologists should be aware of this annoying side effect, particularly when using imiquimod on EMPD. Fig. 1 (A) Extramammary Paget's disease lesions around pubic area. (B) Relatively well defined whitish depigmented patches on the imiquimod application sites after 3 months. Fig. 2 The basal layer of epidermis shows no pigmentation (A) at a low magnification view (H&E stain, ×100), and (B) a high magnification view (×400). The basal layer of epidermis shows negative reaction for (C) Fontana-Masson staining ... Fig. 3 Melanocytes in the basal layer of epidermis stained by immunohistochemistry methods using (A) HMB-45 (×400) antibody, and (B) 3,4-dihydroxyphenylalanine staining (×400) were rarely observed in the depigmented lesions.

Extramammary Paget's Disease: Extended Subclinical Growth Detected Using Three-Dimensional Histology in Routine Paraffin Procedure and Course of the Disease

Extramammary Paget's disease (EMPD) is a rare tumor of the skin characterized by extended irregular subclinical growth and high recurrence rates after surgery. To show that, using three-dimensional (3D) histology in surgical excision, the size of the safety margin can be individually determined and locally adjusted to subclinical growth and to evaluate the course of the disease in 33 patients. The clinical records of 33 patients with primary lesions of EMPD were prospectively documented, retrospectively confirmed, and analyzed. EMPD was found more frequently in women (54.5%). Dermal invasion was found in 21.2%, and regional lymph node metastases were present in one patient; 30.3% of the patients had secondary internal malignancies. In 25 cases examined using 3D histology, a mean surgical margin of 22 mm in asymmetric shape (range 5-65 mm) was achieved, with a recurrence rate of 28%. Surgery with conventional histologic examination had a higher recurrence rate of 62.5% using a mean surgical margin of 19 mm (range 7-40 mm). Subclinical spread of EMPD demonstrated using 3D histology with paraffin sectioning can be large. Three-dimensional histology allows individually defined safety margins to be locally adjusted to subclinical growth and gives low recurrence rates. The authors have indicated no significant interest with commercial supporters.

In vivo reflectance confocal microscopy of extramammary Paget disease: Diagnostic evaluation and surgical management

Extramammary Paget disease (EMPD) is a diagnostic challenge. In vivo reflectance confocal microscopy (RCM) has been reported to be useful for in vivo skin tumor evaluation. It may also assist in the surgical management of EMPD lesions. We sought to describe confocal features of EMPD and correlate them with histopathologic findings. The potential of RCM to map the lesions for subsequent surgical management was also investigated. A total of 23 lesions from 14 recruited patients were evaluated by RCM and histopathologic examination. RCM was used to delineate preoperative surgical margins in two patients. Erythematous, hyperpigmented, and hypopigmented lesions were evaluated by RCM and results were confirmed by histopathologic examination. Paget cells were observed throughout the epidermis. Typical Paget cells on RCM were characterized by a mild bright nucleus and dark cytoplasm, frequently twice the size of keratinocytes or larger. At the dermoepidermal junction, tumor nests were seen as dark glandular structures. A high density of dendritic cells was observed in pigmented lesions and a low density in erythematous lesions. Dilated vessels and inflammatory cells were seen in pigmented and erythematous lesions. Paget cells within the epidermis and nest structures at the dermoepidermal junction were seen in most lesions. These two features were useful for delineating the margins. Histologic examination corroborated the surgical margins found by RCM. The sensitivity and specificity of these diagnostic features have not been fully studied, and differential diagnostic features require exploration. Features correlating well to histopathology are observed on the RCM of EMPD lesions. RCM may be used as an auxiliary diagnostic tool for the diagnosis and management of EMPD.

Expressions of mucin 1 and 2 in lesions of extramammary Paget's disease

Objective To study the expressions of mucin (MUC) 1 and 2 in extramammary Paget's disease(EMPD) lesions. Methods Tissue specimens were obtained from the lesions of 19 patients with EMPD and normal skin of 19 human controls during cosmetic surgery. Streptavidin-perosidase (SP) technique was used to detect the expressions of MUC1 and MUC2 in these specimens. Results As haematoxylin-eosin (HE) staining showed, 3 cases were accompanied by poorly differentiated adenocarcinoma, 6 were invasive Paget's disease and 10 were intraepithelial EMPD. MUC1 was expressed in 2 cases accompanied by poorly differentiated adenocarcinoma, and in all the cases of invasive and intraepithelial EMPD; MUC2 was observed in all the cases of adenocarcinoma-complicated EMPD and invasive EMPD, but only in 2 of 10 cases of intraepithelial EMPD.Neither MUC1 nor MUC2 was observed in normal control specimens. A significant increase was observed in the expression of MUC1 in lesions of intraepithelial EMPD compared with invasive EMPD and adenocarcinoma-complicated EMPD (both P ＜ 0.05), and in the expression of MUC2 in lesions of invasive EMPD and adenocarcinoma-complicated EMPD compared with intraepithelial EMPD (both P ＜ 0.05). The expression of MUC1 was uncorrelated to that of MUC2 (r= -0.5, P＞ 0.05). Conclusions MUC1 is generally expressed in the lesions of EMPD, while MUC2 is expressed in those of adenocarcinoma-complicated EMPD and invasive EMPD. Key words: Paget's disease, extramammary; Mucins; Gene expression