Immunohistochemical study of c-erbB-2 oncoprotein expression in extramammary Paget's disease

Reviewing vulvar Paget's disease molecular bases. Looking forward to personalized target therapies: a matter of CHANGE

OBJECTIVES

To review the published literature on vulvar Paget's disease (VPD) molecular bases, aiming to support the need for tailored treatment in women affected by this 'orphan' tumor.

METHODS

MEDLINE-PubMed and Scopus were interrogated using the following algorithm: (extramammary OR extra mammary OR vulvar) AND (paget OR pagets OR paget's) AND (molecular OR biological OR marker OR protein OR target OR expression). The inclusion criteria for papers were: peer-reviewed English-language journals, articles published in the last 30 years, studies focused on fixed research questions, quality assessment on the basis of the relevance and contribution to the selected topics.

RESULTS

A total of 42 studies were selected, providing the following results. Molecular markers implicated in cell cycle transitions seem to be related to prognosis and could help to tailor conventional treatments. Fragmented but consistent preliminary data exist on hormonal receptor expression, ERBB2 amplification/overexpression and abnormal vascular proliferation, offering a concrete possibility for target therapy trials. Conversely, other fields linked to the possible use of immunotherapy are currently relatively unexplored, such as the tumor 'immune contexture', programmed death ligand-1 (PD-L1) expression and defects in the mismatch repair system, which is involved in genomic instability and potentially promotes a consistent response to treatment.

CONCLUSIONS

Additional effort is needed to further characterize these aspects. Centralization of patients in dedicated units would be beneficial for concentrating patient numbers, collecting valuable clinical data and conducting clinical trials. Interdisciplinary study platforms should be developed and integrated into wider multicentric networks.

Immunohistochemical and fluorescence in situ hybridization studies on noninvasive and invasive extramammary Paget's disease

To determine useful immunohistochemical markers for tumor cells in extramammary Paget's disease (EMPD), immunohistochemical (IHC) examinations in 17 patients with EMPD, including 4 patients with dermal invasion, were performed. Among the antibodies examined, cytokeratin 7 (CK7) and CK19 were strongly positive for both intraepidermal and dermally invasive tumor cells in all patients. CAM5.2 and mucin 1 (MUC1) were also good markers. Although IHC examination revealed positive for HER-2 in 4 EMPD patients with dermal invasion, 4 out of 13 noninvasive patients were IHC negative. Fluorescence in situ hybridization (FISH) study revealed negative results for HER-2 gene amplification in 8 IHC positive patients, including each 4 patients of both noninvasive and dermal invasive cases. Our results show that besides CK7, CK19 is another favorable marker of tumor cells of EMPD. Four patients with dermal invasion were strongly positive for HER-2, although negative results were obtained in the FISH study. Further investigations are required to confirm the results of the FISH study.

XRCC1 Arg194Trp polymorphism, risk of nonmelanoma skin cancer and extramammary Paget's disease in a Japanese population

The X-ray repair cross-complementing groups 1 gene plays an important role in base excision repair. At least three common single nucleotide polymorphisms frequently occur in this gene (Arg399Gln, Arg194Trp and Arg280His). Recent studies reported that these polymorphisms were associated with not only risk of visceral malignancy but also that of skin cancer such as basal cell carcinoma and squamous cell carcinoma, whereas the results of previous study vary among races. In this case–control study, we investigated whether these single nucleotide polymorphisms were associated with the risk of skin cancer in a Japanese population. The study population was composed of 197 patients with skin cancer (27 actinic keratoses, 47 basal cell carcinomas, 27 squamous cell carcinomas, 29 Bowen’s diseases, 46 malignant melanomas and 21 extramammary Paget’s diseases) and 93 control subjects. We genotyped two single nucleotide polymorphisms (Arg194Trp and Arg399Gln) using polymerase chain reaction-restriction fragments length polymorphism analysis. We found a significantly increased risk for basal cell carcinoma, squamous cell carcinoma and extramammary Paget’s disease associated with Arg194Trp [adjusted odds ratio (AOR) = 2.347, 3.587, 3.741, 95 % confidence interval (CI) 1.02–5.39, 1.19–10.8, 1.15–12.2, respectively]. We also found a significantly decreased risk for basal cell carcinoma associated with Gln399Gln (AOR = 0.259, 95 % CI 0.07–0.96). Our data suggest that the Arg194Trp polymorphism could be associated with nonmelanoma skin cancer and extramammary Paget’s disease risk in a Japanese population.

Mammary Paget's disease and extra-mammary Paget's disease: two morphologically similar but biologically different diseases

BACKGROUND

The cells of origin of mammary Paget's disease (MPD) and extra-mammary Paget's disease (EMPD) have been a controversial subject. The purpose of this study is to examine the expression of the human epidermal growth factor receptor 2 (HER2) pathway members in these two diseases.

DESIGN

HER2, AKT, pAKT, PTEN, epidermal growth factor receptor (EGFR) and pEGFR were examined in 16 MPD and 14 EMPD cases. HER2 was graded on a scale from 0 to 3. A score of 3 was considered positive. For AKT, pAKT, PTEN, EGFR and pEGFR, a semi-quantitative scoring system was used. A score >100 was considered positive. Fisher's exact test was used to analyze the data.

RESULTS

HER2 was overexpressed in 87.5% MPD and 35.7% EMPD. While AKT was expressed in all cases, pAKT was expressed in 87.5% MPD and 92.9% EMPD. Both EGFR and pEGFR were negative in all cases. PTEN was positive in 62.5% MPD and 71.4% EMPD. For pAKT+ group, HER2-/PTEN+ was recorded in 0% MPD and 38.5% EMPD (P = .01).

CONCLUSIONS

In a subset of EMPD, AKT is not activated by HER2 overexpression or by loss of PTEN, which is not the case in MPD. These data suggest that these two diseases are biologically different.

Extramammary Paget's disease-a proliferation of adnexal origin?

AIM

To investigate a possible follicular origin of extramammary Paget's disease (EPD). EPD is a predominantly intraepidermal tumour with extensive involvement of adnexal structures and high recurrence rates suggesting a follicular stem cell origin. Cytokeratin (CK) 15 and CK19 are considered markers for follicular stem cells located in the hair follicle bulge region.

METHODS AND RESULTS

Formalin-fixed paraffin-embedded tissues of 12 cases of primary EPD (three anal, nine vulvar) were studied immunohistochemically with antibodies to CK15 and CK19. All cases of EPD showed polygonal Paget cells in the interfollicular epidermis, hair follicles, sebaceous and apocrine glands distributed individually, in nests and in gland-like areas. The polygonal Paget cells were intimately associated with small, flat, mitotically active, 'compressed' keratinocytes. The large Paget cells uniformly expressed CK19 in 12/12 EPD. The small 'compressed' keratinocytes showed strong cytoplasmic CK15 staining in 9/12 EPD with focal accentuation, while the polygonal Paget cells were negative.

CONCLUSIONS

These histological and immunohistochemical observations allow the following conclusions: (i) the small, flat, 'compressed' keratinocytes are an integral part of EPD; (ii) the dual cell population is reminiscent of sebaceous glands with mature sebocytes and germinative keratinocytes; (iii) since both cell types express cytokeratins typical for follicular differentiation, EPD may be a proliferation of adnexal stem cells residing in the infundibulo-sebaceous unit of hair follicles and adnexal structures.

Comparative genomic hybridization in extramammary Paget's disease

BACKGROUND

Extramammary Paget's disease (EMPD) is a distinct skin cancer of unknown histogenesis. Data from genome-wide surveys for chromosomal aberrations in EMPD are limited.

OBJECTIVES

To identify chromosomal aberrations that are present in EMPD.

METHODS

Fifteen cases of EMPD were analysed by comparative genomic hybridization (CGH). We used pooled DNA CGH, instead of studying a single sample. In addition, immunohistochemistry was performed for detection of androgen receptor (AR).

RESULTS

The most recurrent change was amplification at chromosomes Xcent-q21 and 19, and loss at 10q24-qter. In addition, expression of AR, located in chromosome X, was found in six cases.

CONCLUSIONS

Results suggest that AR may play a role in EMPD tumorigenesis.

PIG7/LITAF gene mutation and overexpression of its gene product in extramammary Paget's disease

To identify cancer-related genes that are involved in the carcinogenesis of extramammary Paget's disease (EMPD), we compared mRNA expression profiles of EMPD lesions and corresponding normal skin using cDNA array. Sixty-eight genes were highly expressed (>5-fold) in EMPD lesions compared to normal skin, and 40 genes were expressed less than one-fifth in EMPD lesions. Among them, PIG7/LITAF mRNA was overexpressed in 3 of 4 EMPD cases. PIG7/LITAF transcription is induced by p53 expression and has been implicated in the p53-induced apoptotic pathway. Since expression of p53 mRNA and p53 protein was not high in any of the 3 EMPD samples compared to the intact skin of the same patient, we analyzed PIG7/LITAF cDNA mutations among 12 EMPD samples (including the former 4) by PCR-SSCP. Three samples showed shifted bands (2 had point mutations leading to amino acid substitutions and 1 had a silent mutation). One sample with amino acid substitution overexpressed PIG7/LITAF mRNA in cDNA array analysis and RT-PCR. PIG7/LITAF mRNA expression is confined to tumor cells in in situ mRNA hybridization analysis. These results indicate that genetic disorder and overexpression of PIG7/LITAF may be involved in EMPD carcinogenesis.

HER2 oncogene amplification in extramammary Paget's disease

AIMS

To study HER2 oncogene amplification and over-expression in skin samples of 23 patients with extramammary Paget's disease (EMP). EMP is a rare intra-epidermal adenocarcinoma, which has been reported to over-express the HER2 oncoprotein.

METHODS AND RESULTS

HER2 gene amplification, detected by chromogenic in-situ hybridization, was found in 43% (10/23) of the lesions. HER2 protein over-expression (3+ immunostaining intensity) was found in 12 tumours (52%), including all 10 tumours with gene amplification. Two tumours showed low-level (2+) HER2 immunostaining. Mammary Paget's lesions, which were used as controls, showed HER2 amplification and over-expression in all 10 cases studied.

CONCLUSIONS

These results indicate that HER-2 protein over-expression in EMP is common and due exclusively to gene amplification. They open up the possibility of HER2-targetted immunotherapy for patients with HER2+ disease.

Mammary Paget's disease: evidence of diverse origin of the disease with a subgroup of Paget's disease developing from the superficial portion of lactiferous duct and a discontinuous pattern of tumor spread

The pattern of spread of intraductal carcinoma associated with mammary Paget's disease has not been well studied. The purpose of this study was to examine the site of origin and the pattern of tumor spread with a three-dimensional view by serial sectioning of the tissue blocks from 19 cases of Paget's disease. Intraductal carcinoma in the superficial portion of the lactiferous ducts was seen in continuity with the overlying epidermis with Paget's disease in all 19 cases. In seven cases that had adequate tissue sampling, five showed a continuous pattern of the intraductal carcinoma within the superficial as well as the deep breast tissue. In the remaining two cases, a portion of benign duct was identified between the intraductal carcinoma in the superficial lactiferous duct and the deep breast tissue. This discontinuous pattern of spread of the intraductal carcinoma was also identified in the foci of carcinoma in deep tissue. In the five cases in which the tumor involved the skin and only the superficial portions of the lactiferous duct, the leading edge of the intraductal carcinoma was seen orientated in the direction of the nipple towards the deep breast tissue. Our study of Paget's disease demonstrated that in addition to tumor spread along the lactiferous ducts from intraductal carcinoma in the deep tissue towards the nipple, there was a group of Paget's disease arising from the nipple. These lesions included: (i) lesions limited to the areolar tissue; and (ii) lesions with intraductal carcinoma involving the duct system in both superficial and deep breast tissue with and, possibly, without skip areas pattern of spread. Although certain cases of Paget's disease may appear superficial, an independent associated carcinoma in deep breast tissue has to be ruled out.

erbB-2 overexpression but no activation of beta-Catenin gene in extramammary Paget's disease

Our previous study in extramammary Paget's disease showed neither p53 mutations nor allelic loss at selected loci implicated in other cancers, suggesting a pathogenesis of this skin cancer different from other common epithelial malignancies. To examine further the genetic defects in extramammary Paget's disease, we carried out molecular genetic analyses in 31 tumor samples obtained from 27 cases of extramammary Paget's disease without underlying malignancies. Immunohistochemistry using CB-11 monoclonal antibody revealed either membrane or cytoplasmic erbB-2 oncoprotein overexpression in none of the 13 primary in situ tumors, but in one recurrent in situ tumor, 10 of 13 invasive primary tumors and two of four lymph node metastases. Sensitive dual color fluorescence in situ hybridization analysis using probes for erbB-2 gene locus and chromosome 17 pericentromere, however, revealed different erbB-2 gene status in the erbB-2 overexpressing tumors. One recurrent in situ tumor and one lymph node metastasis showed definite gene amplification characterized by multiple scattered signals or a few large clustered erbB-2 signals, whereas four tumors with predominantly cytoplasmic erbB-2 overexpression were thought to have low-grade gene amplification. The remaining six tumors overexpressing erbB-2 showed no increase of erbB-2 copy numbers. No evidence of abnormal activation of the beta-catenin gene, a critical mediator of Wnt signaling pathway, in any tumor by immunohistochemical staining and by direct sequencing and reverse transcription-polymerase chain reaction analysis was found. Frequent overexpression of erbB-2 by either gene amplification or possible transcriptional activation in invasive primary tumors and metastases suggests an important part for this oncogene in the progression of extramammary Paget's disease.

Long-term outcome of patients with perianal Paget's disease

BACKGROUND

Perianal Paget's disease (PPD) is a rare intraepithelial adenocarcinoma with a significant rate of recurrence after treatment and high risk of progression to an invasive cancer.

PATIENTS AND METHODS

Fourteen patients with a mean follow-up longer than 5 years were studied to determine the outcome after surgical treatment. The immunohistochemical accumulation of p53 protein also was assessed in tissue specimens to evaluate its prognostic role in patients with PPD.

RESULTS

Four patients were excluded because of progression to invasive malignancy at the time of diagnosis. Two patients underwent local excision (LE) with macroscopic clearance of the surgical margins; the remaining eight patients underwent wide local excision (WLE), i.e., > 1 cm microscopic clearance of the surgical margins. The actuarial 8-year recurrence rate for patients treated with LE and WLE was 100% and 50% (SE = 17.7), respectively. Progression to invasive carcinoma occurred after a median time of 56 months (range 23-72) in two patients treated with LE and in one of eight patients treated with WLE. All four patients with recurrence after WLE were successfully treated (no further recurrence) with a second WLE. Actuarial 8-year survival was 0% in the LE group and 40% (SE = 21.9) in the WLE group. There was no p53 protein accumulation in any of the ten patients with PPD.

CONCLUSIONS

Survival of patients with PPD treated by WLE was higher than that for those treated with LE. Thus, wide local excision is recommended over limited local excision as a preferred treatment for PPD. Follow-up longer than 5 years seems to be indicated because of the risk of late progression to invasive cancer. When PPD does recur, a second WLE may be curative. The absence of accumulated p53 protein suggests that this marker may not have a prognostic role in PPD.

Tumour cells of extramammary Paget's disease do not show either p53 mutation or allelic loss at several selected loci implicated in other cancers

Extramammary Paget's disease is a particular form of skin cancer of unknown histogenesis. To look for the genetic defects underlying the pathogenesis of this tumour, we have examined loss of heterozygosity (LOH), p53 and human papillomavirus (HPV) status, and the expression of c-erbB-2 and bcl-2 proteins in 14 cases. Unexpectedly, no LOH was detected at several loci commonly lost in other human cancers (namely 3p, 9p, 9q, 13q, 16q, 17p, and 17q) in 12 tumours examined. Altered p53 protein expression was entirely or mostly negative in all 14 cases. Direct sequencing of exons 5-8 of the p53 gene in eight cases revealed no mutation. Polymerase chain reaction amplification of the L1 gene of human papillomavirus (HPV) did not detect the virus that could inactivate p53 and retinoblastoma tumour-suppressor gene products. As expected, c-erbB-2 proto-oncogene protein was overexpressed in six cases. The expression of bcl-2 was negative in all cases. The results presented in this study suggest that molecular events underlying extramammary Paget's disease differ from those of other common epithelial malignancies and that tumour-suppressor genes located in chromosome regions not examined in this study may be important.

A comparative immunohistochemical study of mammary and extramammary Paget's disease and superficial spreading melanoma, with particular emphasis on melanocytic markers

A comparative immunohistochemical study was performed on Paget's disease of the nipple (PDN), extramammary Paget's disease (EMPD) and cutaneous superficial spreading melanoma (SSM) using antibodies to S100, NK1-C3 and HMB45, cytokeratin (CAM 5.2) and c-erb B2 oncoprotein (21N). Conventional histochemical stains for intracytoplasmic mucin and melanin were also done. Of the 20 cases of PDN, positivity was seen in 12 with S100, 16 with NK1-C3, none with HMB45, 20 with CAM 5.2 and 19 with 21N. All 5 cases of EMPD were CAM 5.2 positive and HMB45, S100 and 21N negative. Three EMPD were NK1-C3 positive. All 10 cases of SSM were S100, NK1-C3 and HMB45 positive and all were CAM5.2 and 21N negative. Mucin was demonstrable in 11 cases of PDN and all of EMPD but none of SSM. Melanin was seen in 2 PDN, 3 EMPD and all SSM cases. Identification of mucin and melanin, therefore, proved an unreliable means of distinguishing these diseases. Immunohistochemistry for cytokeratin and HMB45 appear to be the most specific markers in differentiating Paget's disease and SSM. Antibodies to c-erb B2 may also be valuable in this situation.