Pl6 expression in Paget's disease of the breast

BACKGROUND

Paget's disease of the nipple is generally associated with an underlying invasive cancer or an underlying ductal carcinoma in situ. Epidermotropic theory maintains that Paget's cells are derived from an underlying mammary in situ adenocarcinoma. Because p16 protein plays a major role in cell-cycle control and in tumoral cell mobility, we analyzed p16 expression in Paget's disease of the nipple and in associated underlying ductal carcinoma in situ.

METHODS

The expression of p16 protein was analyzed by immunohistochemistry in eight cases of Paget's disease of the nipple with associated underlying ductal carcinoma in situ. The Student's t-test (2-tailed) was used to establish the equality of means.

RESULTS

The expression of p16 protein was observed in 87.5% (7/8 cases) both in the nipple disease and in the associated underlying ductal carcinoma in situ. The difference between the two populations was not statistically significant. In normal breast tissue, no expression of the protein was observed.

CONCLUSION

The positive p16 expression in Paget's disease of the nipple and the underlined ductal carcinoma in situ and its role in cell motility lead us to propose a role of p16 in the spread of this disease.

Acinar Pattern of Mammary Paget?s Disease: A Case Report

Mammary Paget's disease (MPD) is an uncommon in situ neoplasm of the nipple-areolar complex and surrounding skin. It is almost always associated with mammary ductal carcinoma in situ (DCIS), high-grade or invasive carcinoma, usually of ductal origin. MPD has only rarely been described in association with specialized forms of breast carcinoma. We report an unusual case of an acinar pattern of MPD with low-grade cytological atypia, associated with invasive papillary carcinoma and micropapillary DCIS of the lactiferous ducts, in an 83-year-old woman. Most cases of MPD are characterized by intraepidermal spread of discohesive glandular epithelial cells with high-grade nuclear atypia. A predominant acinar pattern of MPD is extremely uncommon and, to our knowledge, has not been formally reported. The histological features and differential diagnosis are discussed.

Expression of cytokeratin subtypes in intraepidermal malignancies: a guide for differentiation

BACKGROUND

Among intraepidermal malignancies of epithelial origin, Bowen's disease, bowenoid actinic keratosis (BAK), intraepidermal malignant eccrine poroma (MEP), and Paget's disease may pose diagnostic difficulties.

METHODS

Histologic features and immunohistochemical profiles of 24 cases of Bowen's disease, 21 cases of BAK, 18 cases of intraepidermal MEP, and 11 cases of Paget's disease were analyzed.

RESULTS

Using multivariate logistic regression test, multinuclear giant cells and solar degeneration were found to be the only histologic parameters of diagnostic help. On the other hand, a widespread positive reaction for CK 5/8, CK 7, CK 19, and negative reaction for CK 10, was a helpful feature in the differentiation of Paget's disease from Bowen's disease and BAK. The widespread and strong expression of CK 10 was seen in almost all cases of Bowen's disease in contrast to BAK. The widespread expression of CK 5/8 and CK 7, and negative reaction for CK 10, was in favor of Paget's disease, compared to intraepidermal MEP. On the other hand, widespread expression of CK 19 was a common finding in intraepidermal MEP, in contrast to Bowen's disease.

CONCLUSION

An immunohistochemical panel may provide significant hints on the differentiation of common intraepidermal malignancies, especially in problematic cases.

Assessment of Her-2/Neu status by immunohistochemistry and fluorescence in situ hybridization in mammary Paget disease and underlying carcinoma

HER-2/Neu overexpression is seen in 20% to 30% of invasive breast carcinomas and has been reported in as many as 80% of high-grade infiltrating carcinomas. Earlier studies have suggested that 100% of the tumor cells in mammary Paget disease show overexpression of HER-2 protein. We undertook this study to assess HER-2 status of mammary Paget disease and of the underlying breast carcinoma, when present, by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Formalin-fixed, paraffin-embedded tissue from 20 cases of mammary Paget disease were analyzed for HER-2 status by IHC and FISH. IHC for estrogen receptor (ER) was also performed. The patients ranged in age from 34 to 88 years, with a mean age of 62 years. Eighty percent of the cases showed strong overexpression (3+) of HER-2 protein by IHC, and all of these cases showed more than 5-fold amplification of the HER-2 gene by FISH. The remaining 4 cases, which were negative for HER-2/Neu by IHC, showed no amplification by FISH. All of the latter cases expressed ER, whereas no case that overexpressed HER-2 expressed ER. Sixteen cases had an underlying tumor, which was in situ in 6 cases. The underlying tumors were identical to the Paget disease with respect to their HER-2/Neu overexpression by both IHC and FISH. HER-2 overexpression was identified in 80% of our cases of Paget disease. There was 100% concordance between HER-2 protein overexpression by immunohistochemistry and gene amplification in both the Paget and the underlying tumor. Moreover, all of the cases negative for HER-2 overexpression expressed ER, whereas those positive for HER-2 did not.

Toker cells are probably precursors of Paget cell carcinoma: a morphological and ultrastructural description

The present paper documents an investigation of the morphology, immunohistochemistry, and ultrastructure of Toker cells (TC), aiming for a better definition of these elements and better understanding of their histogenesis. We studied 12 nipples removed for nipple adenoma from twelve patients and a case of supernumerary nipple. In addition four cases of Paget's carcinoma (PC) restricted to the nipple without underlying tumor were studied for comparison. All cases were stained with hematoxylin and eosin (H&E), Alcian blue pH 2.5 and periodic acid-Schiff (PAS) preceded by diastase digestion and with immunohistochemistry using antisera anti cytokeratin 7, cytokeratin 20, protein S100, GCDFP-15, c-Erb-B2, CAM 5.2, and epithelial membrane antigen (EMA). Two cases from the nipple adenoma series were studied by electron microscopy. In seven cases within the series of 12 nipple adenomas as well as in the case of supernumerary nipple, keratin 7 antibody highlighted numerous cells located within the nipple epidermis which in three cases showed dendritic processes. These same elements were also positive with CAM 5.2. All these same elements were negative with Alcian Blue (AB), PAS and the other antisera employed. Ultrastructural examination demonstrated that these cells differed from keratinocytes while they presented the same features as the glandular cells seen in the related nipple adenoma. The cells constituting Paget's carcinoma showed more irregular nuclei and were more easily seen in the context of the epidermis. The immunocytochemical profile of the cancer cells was similar to that of TC, but in addition the neoplastic cells were c-Erb-B2 and EMA positive in all cases, and one case also displayed numerous cells immunoreactive with anti GCDFP-15 antibody. Keratin 7 highlighted dendritic cells in two cases and AB, PAS was negative in all patients. The immunocytochemical profile and the ultrastructural features of TC are similar to those of the glandular cells constituting the ducts and the adenoma. These findings together with the localization of TC near or around the openings of the lactiferous sinuses indicate that TC might be ductal cells with a dendritic aspect and migrate through the galactophorous ostia. PC cells not related to ductal carcinomas have a similar but not superimposable immunohistochemical profile to TC, and in two cases the neoplastic elements were also dendritic which suggests that these same cells are likely to be the neoplastic counterpart of TC.

The role of p53 and Ki67 in Paget's disease of the vulva and the breast

OBJECTIVE

Paget's disease of the vulva (PDV) and Paget's disease of the breast (PDB) are uncommon diseases, accounting for approximately 1% of all vulval neoplasms and 0.5-4% of all breast cancers, respectively. In 10-30% of vulval cases an invasive adenocarcinoma is present. In such cases the disease is often aggressive and recurrence rate is high. This is in contrast to PDB where the general consensus is that almost all cases are associated with an in situ or invasive ductal carcinoma. Our aim was to examine the presence of the tumor suppressor protein p53 and the proliferation marker Ki67 in PDV and PDB and correlate any differences in the expression of these two proteins with the presence of an underlying carcinoma.

METHODS

Immunohistochemistry was performed on 52 archival cases of PDV, which included 10 with associated invasive adenocarcinoma of the vulva, and on 37 archival cases of PDB, including 26 with available associated ductal carcinoma in situ (DCIS) or invasive carcinoma of the breast. All cases were formalin-fixed and paraffin wax-embedded. Monoclonal antibodies were used with microwave antigen retrieval. Streptavidin-biotin-horseradish peroxidase and 3,3'-diaminobenzidine detection methods were employed to visualize antibody binding and staining. A section was scored positive for p53 if more than 10% of cell nuclei were stained brown and Ki67 was expressed as a percentage of positive cells to the nearest 5% of cells showing nuclear positivity (Ki67 staining index).

RESULTS

p53 was expressed in 15 of 52 (29%) PDV cases and 5 of 37 (13%) cases of PDB. Four of the ten cases (40%) of PDV associated with invasive disease expressed p53 compared with 11 of 42 (26%) cases without invasive disease. The mean Ki67 staining index for PDV associated with invasion was 19%, and for that without invasion, 16%. In the breast cases, the mean staining index was 11%.

CONCLUSION

Our data suggest that p53 may have a role to play in PDV progression, and may be a late event in some cases, especially those associated with invasive disease. Ki67 has no apparent prognostic role in PDV as there was no significant difference between those cases associated with and those without invasive disease. Neither p53 nor Ki67 appears to have a prognostic role to play in PDB.

Molecular markers in Paget disease of the breast

BACKGROUND AND OBJECTIVES

Molecular markers are increasingly being analyzed in tumor specimens because of their relevance to both prognosis and choice of therapy. Paget disease of the breast is an uncommon form of breast cancer, in which molecular markers have not been well characterized. The objective of this study was to investigate the expression of c-erbB-2, p53, Ki-67, Cyclin D1, Bcl-2, estrogen receptors (ER), and progesterone receptors (PR) in mammary Paget disease.

METHODS

Archival tumor tissues from 14 patients diagnosed between 1990 and 1999 with Paget disease of the breast were analyzed for these molecular markers by using an automated immunohistochemical assay. Both the intraepidermal Paget cells and the underlying carcinoma were assessed for these markers.

RESULTS

The majority of Paget cells were positive for c-erbB-2 (92.9%), Cyclin D1 (100%), and Ki-67 (85.7%), but very few were positive for Bcl-2 (14.3%). p53 was overexpressed in 42.9% of the cases, and only 28.6% were positive for ER and PR. The rate of expression of these biologic markers was similar in both the Paget cells and the underlying intraductal and/or ductal carcinoma cells.

CONCLUSIONS

Tumors from patients with Paget disease of the breast were positive for c-erbB-2, Cyclin D1, and Ki-67, molecular markers commonly associated with more aggressive tumor behavior and poorer survival in breast cancer patients. Few of these tumors expressed Bcl-2 or ER and PR, which are generally associated with a better prognosis. Similar expression of these markers in both Paget cells and the underlying carcinoma supports the theory that these cells are the result of an intraepidermal spread of ductal carcinoma.

Morphological evidence for field effect as a mechanism for tumour spread in mammary Paget's disease

AIMS

The histogenesis of mammary Paget's disease is controversial. The purpose of this study was to investigate the mechanism of tumour spread in the nipple epidermis by examining 28 cases of mammary Paget's disease associated with underlying intraductal carcinoma.

METHODS AND RESULTS

The atypical cells in the epidermis displayed a spectrum of cytological changes ranging from small-sized atypical cells located in the basal cell layer to large-sized atypical cells characteristic of Paget's cells in the upper layer of the epidermis. Serial sectioning revealed the presence of isolated, scattered and small atypical cells in the basal cell layer at the periphery of the epidermal lesion. The atypical cells, including those in the basal cell layer showed positive immunostaining for cytokeratin 7 and Her2/neu oncoprotein. Electron microscopy examination demonstrated the presence of intercellular junctions of desmosomal-like or desmosomal types between tumour cells and adjacent squamous cells. Furthermore, examination of the intraductal carcinoma of the breast tissue in cases of Paget's disease as well as control cases of intraductal carcinoma also revealed areas of skip lesions of intraductal carcinoma.

CONCLUSIONS

In view of these changes, it is unlikely that tumour expansion or tumour cell motility are sufficient explanations to account for the pattern of tumour spread in both the epidermis and the duct epithelium with skip lesions. A 'field effect' in the duct system harbouring intraductal carcinoma and the adjacent epidermis may play an important role in the tumour cell spread in the epidermis as well as in the ductal epithelium.

99m Tc MIBI prone scintimammography in breast Paget's disease: a case report

A 99m Tc MIBI prone scintimammography (PSM) was performed in a case of underlying Paget's disease of the breast. 99m Tc MIBI PSM showed a diffuse scintigraphic image like a spread of uptake from the deeply located zones of the breast toward epidermis. In vivo, 99m Tc MIBI PSM represents the spread of neoplastic Paget's cells probably attracted by chemotactic factors released by keratinocytes. This spread in Paget's disease is correlated to neu oncogene overexpression which increases the metastatic activity as a consequence of motility enhancement and growth stimulation effect. These scintigraphic images suggest that 99m Tc MIBI PSM could be relevant in management of Paget's disease of the breast.

Expression of desmogleins in Paget cells of mammary and extramammary Paget's disease

Sagebiel (1969) electronmicroscopically observed that desmosomes are present between adjacent Paget cells, as well as between Paget cells and adjacent keratinizing epidermal cells. Desmosomes contain the proteins desmoglein (Dsg) and desmocollin as their transmembrane components, and Dsg has three isotypes. Among the three isotypes of Dsg, Dsg1 and Dsg3 are autoantigens for pemphigus foliaceus and pemphigus vulgaris (PV), respectively. We examined the expression of Dsgs in Paget cells of mammary and extramammary Paget's disease. Skin samples were obtained from one patient with mammary Paget's disease, and from 2 with extramammary Paget's disease. One part of the samples was cut into small pieces and epidermal sheets were separated with dispase, then treated with a mixture of EDTA and trypsin. The resulting cell suspensions were cultured in low Ca++ medium, then the cells were incubated in high Ca++ medium. Paget cells identified with anti-epithelial membrane antigen (EMA) antibody were positive for serum from a PV patient which was confirmed to react with both Dsg1 and Dsg3. However, the intensity of fluorescence of Paget cells was weaker than that of EMA-negative keratinocytes. In the cryostat sections, Paget cells identified with anti-EMA antibody showed the same staining pattern as cultured cells in high Ca++ medium. The data presented in this study confirm that Paget cells express Dsgs, and are consistent with the electronmicroscopical data by Sagebiel (1969). However, our data do not support the hypothesis that Paget cells are of keratinocyte origin, because sweat ducts or sweat glands could be positive for sera from PV patients. It is necessary to confirm whether or not sweat ducts or sweat glands express Dsgs, because sera from PV patients exhibit high background in the dermis.

[Expression of the c-erbB-2 oncoprotein in mammary Paget's disease. Immunohistochemical study by using 3 antibodies]

An overexpression of the c-erbB-2 oncoprotein has been demonstrated in the breast cancer and has been associated with a poor prognosis. Our study involved 23 cases of mammary Paget's disease which was found to be associated with the intraductal carcinomas in 13 cases, the intraductal carcinomas supposed micro-invasive in 2 cases, the infiltrating ductal carcinomas with predominant intraductal component in 6 cases and the infiltrating ductal carcinomas in 2 cases. The presence of c-erbB-2 oncoprotein has been determined immunohistochemically with 3 different antibodies: rabbit anti-human c-erbB-2 oncoprotein A485 (Dako), c-erbB-2 oncoprotein (internal domain) mouse monoclonal antibody NCL-CB11 (Novocastra), and c-erbB-2 oncoprotein (external domain) mouse monoclonal antibody NCL-CBE1 (Novocastra). An overexpression of the c-erbB-2 oncoprotein has been observed in 21 of the 23 studied cases. We noted an intense membrane staining in the intraepidermal or intraglandular tumour cells of mammary Paget's disease. Any staining has been observed in 2 cases with glandular component of pure intraductal type. These results are identical whatever the antibody used. In a previous study concerning mammary Paget's disease, it has been noted a correlation between this overexpression and presence of large malignant cells. We also have found this notion in mammary Paget's disease where the c-erbB-2 positive neoplastic cells in the different tumour components were large with prominent cytoplasm. The obtained results argue strongly for adenocarcinomatous origin for mammary Paget's disease and exhibit that the overexpression of c-erbB-2 oncoprotein was not constantly in correlation with a poor prognosis.

Immunohistochemical study of mammary and extramammary Paget's disease

Immunophenotypes of mammary (MPD) and extramammary Paget's disease (EPD) are still not well understood. Thirty-four formalin-fixed paraffin-embedded tissue sections from 33 patients with 6 MPD and 28 EPD were studied immunohistochemically with the use of polyclonal c-erbB-2 and pS2 antisera, and monoclonal nm23, B6.2, GCDFP-15, and p53 antibodies. Cases of MPD expressed a high incidence of c-erbB-2 and nm23 compared with those of EPD (100% vs. 29%; p < 0.01, and 83% vs. 29%; p < 0.05, respectively). Although high expression of B6.2 (> 83%) and moderate expression of GCDFP-15 (33-39%), pS2 (33-46%) and p53 (39-50%) were seen, the positivity was not significantly different between MPD and EPD. These findings indicate that MPD and EPD share immunohistochemical features but partially differ in their patterns of antigen expression.

The neu-protein and breast cancer

The neu-protein is overexpressed in about 20% of invasive duct cell carcinomas of the breast. The only reliable sign for neu-overexpression by immunohistochemistry is membrane staining. Its overexpression is correlated with decreased overall survival and disease free survival due to increased metastatic activity of neu-overexpressing tumour cells. This increased metastatic potential is a consequence of the motility enhancing activity of the neu-protein, which is exclusively expressed on pseudopodia, and to a lesser extent of its growth stimulating effect. From a clinical point of view, the assessment of neu-overexpression in breast cancer might become a useful tool in the future treatment of patients by chemotherapy, since patients whose tumour shows neu-overexpression benefit from higher doses of chemotherapy. The molecule plays a key role in the pathogenesis of Paget's disease of the breast. A chemotactic factor which is secreted by epidermal keratinocytes attracts the Paget cells to spread into the epidermis and acts via the neu-protein. In ductal carcinoma in situ, the combination of neu-overexpression and large cell type is highly correlated with extent of disease and therefore neu-overexpression might be a predictive marker for recurrence of disease after tumour resection.

Keratinocyte induced chemotaxis in the pathogenesis of Paget's disease of the breast

In Paget's disease of the breast, the epidermis contains large clear neoplastic cells. To explain the pathogenesis of this disease, the immunohistochemical characteristics of these cells were investigated in 25 patients. The cytoplasmic presence of low molecular weight cytokeratin and the absence of high molecular weight cytokeratin in all cases confirmed the glandular origin of the Paget cells. Membrane over-expression of the neu-protein was established in 96% of cases. It was hypothesized that epidermal keratinocytes release a chemotactic factor which attracts neu-over-expressing breast carcinoma cells by chemotaxis into the epidermis. The biological assays showed that normal keratinocytes release one or more chemotactic factor(s) into their conditioned medium, which induced spreading and motility of neu-over-expressing SK-BR-3 human breast cancer cells. The conditioned medium of keratinocytes also attracted the SK-BR-3 cells by chemotaxis in a modified Boyden chamber. Furthermore, MCF-7 human breast cancer cells, which do not over-express the neu-protein, were not attracted by chemotaxis of conditioned medium of human keratinocytes. The involvement of the neu-protein in spreading, motility and chemotaxis is further indicated by the inhibition of these processes by monoclonal antibodies against the extracellular domain of the neu-protein. We conclude, therefore, that the Paget cells spread through the epidermis due to the motility induced by a chemotactic factor, which is released by epidermal keratinocytes and whose influence is mediated by the neu-protein.

A case of mammary Paget's disease without an underlying carcinoma: microscopic analysis of the DNA content in Paget cells

A 72-year-old woman had a 7-year history of a scaly red area on the right breast which had enlarged asymptomatically. A biopsy of the nipple was taken, and, following the finding of Paget's disease, a modified radical mastectomy was carried out. On histological examination of the entire breast specimen by serial sections, no evidence of an intraductal adenocarcinoma was found. Fractionation of Paget cells was performed from the epidermis. Stripped skin was treated with EDTA and trypsin, and epidermal cell suspensions were obtained. They were layered onto discontinuous Percoll gradients and centrifuged. Paget cells fell into three fractions with densities of 1.041, 1.058, and 1.078. Electronmicroscopically, the purity of fractionated cells obtained by this method ranged from 55 to 74% with viabilities of from 70 to 90%. Microscopic analysis of the DNA content in these cells was performed. The DNA histogram was close to the normal ploidy. This may explain why the mammary Paget's disease lesions in this case enlarged rather slowly.

p53 protein expression in mammary and extramammary Paget's disease

p53 is a tumour-suppressor gene, mutations of which are found in malignant skin lesions. We studied the immunohistochemical expression of the (mutated) p53 protein in 17 cases of Paget's disease (12 mammary and 5 extramammary). Four of the mammary specimens (33.3%) expressed p53 within Paget's cells; in one of these an underlying ductal adenocarcinoma was present and this was also p53-positive. All extramammary cases proved p53-negative. These results underline the differences that exist between mammary and extramammary Paget's disease and favour the origin of the former from the underlying adenocarcinoma rather than the surface epithelium.

[Study of c-erbB-2 expression in breast neoplasms]

A monoclonal antibody, NCL-CB11, raised against a synthetic peptide from the predicted sequence of the c-erbB-2 protein has been used immunohistochemically in a retrospective study of formalin-fixed paraffin embedded breast neoplasm biopsies. Sixty-five out of 115 infiltrating ductal carcinoma, eleven out of 15 intraductal carcinoma and seventeen out of 22 mammary Paget's diseases exhibited positive membrane staining, indicating amplification of the gene in these tumours. In infiltrating ductal carcinoma, there was a positive correlation between c-erbB-2 overexpression and axillary lymph node metastasis as well as between the overexpression and the number of mitotic figures. These results suggest that c-erbB-2 expression might be used as a predictive marker for the worse prognosis of breast carcinoma. The significance of c-erbB-2 expression in other malignant tumours and benign lesions is also discussed.

Mammary Paget's disease and associated carcinoma. An immunohistochemical study

Mammary Paget's disease has been said to result from epidermal spread by contiguity of primary intraductal carcinoma. To assess similar identity, we immunostained Paget's cells and underlying intraductal and/or invasive mammary carcinoma in 20 cases for cytokeratins, epithelial membrane antigen, gross cystic disease fluid protein-15, lysozyme, carcinoembryonic antigen, S100 protein, kappa-casein, and alpha-lactalbumin. Steroid receptor immunostain was positive in only one (5%) of the cases of Paget's disease and in two and four (approximately 15%) (for estrogen and progesterone receptor, respectively) of the cases of ductal carcinoma. In 18 patients (90%), the immunohistochemical profile was identical in Paget's cells and associated carcinoma for seven or more antigens. In one patient, there was a definite disparity in the antigenic profile; in another patient, this was dissimilar because of very focal staining in one site. The antigenic similarity between Paget's cells and underlying carcinoma in 18 (90%) of the cases of mammary Paget's disease suggested in favor of their common origin, ie, probably intraepidermal spread of ductal carcinoma. Origin from apocrine/eccrine structures, or multipotent cells in the epidermis, was suggested in a minority.

Paget's disease of the nipple without clinically and radiologically detectable breast tumor. Histochemical and immunohistochemical study of 44 cases

Paget's disease of the nipple is a rare lesion nearly always associated with an underlying breast cancer, clinically impalpable and radiologically undetectable in about 40% of the patients. Fourty-four cases (28 mastectomies and 16 biopsies of the nipple) of Paget's disease of the nipple without clinically and radiologically detectable breast tumor were retrospectively studied by means of histochemistry and immunohistochemistry. Histochemical study showed that Paget cells were PAS positive and diastase resistant, and alcian blue positive at pH 2.5 in 32% and 18%, respectively. Immunohistochemical study showed that Paget cells were EMA and c-erbB-2 positive in 100% and 84%, respectively. Four of the six EMA positive and c-erbB-2 negative cases of Paget's disease of the nipple in which the underlying tumor could be pathologically analyzed were associated with ductal carcinoma in situ of cribriform or mixed types. These findings are helpful for differentiating Paget's disease from other lesions of the nipple, namely Bowen's disease and eczema which do not react with both antibodies, and from nipple adenoma which exhibits a positive staining with anti-EMA antibody and no reactivity with anti-c-erbB-2 antibody.

Morphologic and immunohistochemical observations on the mammary and extramammary Paget's disease: implications for the histogenesis

Using a panel of three anti-CK MoAbs, belonging to Gown's Classes II, III and IV, the Paget's cells shown a variable reactivity to such antibodies indicating a more frequent immunocytochemical similarity to the cells of the epidermal basal-ductal system than to the cells of the glandular secreting section of the epidermal derivatives. According these findings the P.C. not necessarily is the result of a cellular migration from ductal section toward the epidermis, but may arise from a epidermal basal-stem cell, from a ductal or more rarely from glandular secreting cell. This assumption is enforced also by the expression of the CEA from morphologically bonafide basal epidermal cells in proximity of the pagetic lesion.