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

Learning to distinguish progressive and non-progressive ductal carcinoma in situ

Ductal carcinoma in situ (DCIS) is a non-invasive breast neoplasia that accounts for 25% of all screen-detected breast cancers diagnosed annually. Neoplastic cells in DCIS are confined to the ductal system of the breast, although they can escape and progress to invasive breast cancer in a subset of patients. A key concern of DCIS is overtreatment, as most patients screened for DCIS and in whom DCIS is diagnosed will not go on to exhibit symptoms or die of breast cancer, even if left untreated. However, differentiating low-risk, indolent DCIS from potentially progressive DCIS remains challenging. In this Review, we summarize our current knowledge of DCIS and explore open questions about the basic biology of DCIS, including those regarding how genomic events in neoplastic cells and the surrounding microenvironment contribute to the progression of DCIS to invasive breast cancer. Further, we discuss what information will be needed to prevent overtreatment of indolent DCIS lesions without compromising adequate treatment for high-risk patients.

Perianal Paget's Disease Co-Associated with Anorectal Adenocarcinoma: Primary or Secondary Disease?

Perianal Paget's disease (PPD) represents a skin neoplasm which can be either primary or secondary to carcinoma from an adjacent internal organ. PPD with underlying colorectal adenocarcinoma is usually looked upon as a secondary disease. We report a rare case of co-associated PPD and anorectal adenocarcinoma. The PPD was found to be located near the anorectal adenocarcinoma with normal tissues between them. Immunohistochemical stains demonstrated that the Paget's cells were CK7+/GCDFP-15–/CK20–/MUC2–/CDX2–, whereas the anorectal adenocarcinoma was shown to be CK7+/GCDFP-15–/CK20+/MUC2+/CDX2+. This immunological phenotypic profile supported the notion that PPD and anorectal adenocarcinoma were of different origins, but could not define the exact origins of PPD. In our determination, this case was a primary PPD with anorectal adenocarcinoma. PPD remains a heterogeneous and complex pathology, and additional studies are required to differentiate between the various possible origins.

Spectral imaging perspective on cytomics

BACKGROUND

Cytomics involves the analysis of cellular morphology and molecular phenotypes, with reference to tissue architecture and to additional metadata. To this end, a variety of imaging and nonimaging technologies need to be integrated. Spectral imaging is proposed as a tool that can simplify and enrich the extraction of morphological and molecular information. Simple-to-use instrumentation is available that mounts on standard microscopes and can generate spectral image datasets with excellent spatial and spectral resolution; these can be exploited by sophisticated analysis tools.

METHODS

This report focuses on brightfield microscopy-based approaches. Cytological and histological samples were stained using nonspecific standard stains (Giemsa; hematoxylin and eosin (H&E)) or immunohistochemical (IHC) techniques employing three chromogens plus a hematoxylin counterstain. The samples were imaged using the Nuance system, a commercially available, liquid-crystal tunable-filter-based multispectral imaging platform. The resulting data sets were analyzed using spectral unmixing algorithms and/or learn-by-example classification tools.

RESULTS

Spectral unmixing of Giemsa-stained guinea-pig blood films readily classified the major blood elements. Machine-learning classifiers were also successful at the same task, as well in distinguishing normal from malignant regions in a colon-cancer example, and in delineating regions of inflammation in an H&E-stained kidney sample. In an example of a multiplexed ICH sample, brown, red, and blue chromogens were isolated into separate images without crosstalk or interference from the (also blue) hematoxylin counterstain.

CONCLUSION

Cytomics requires both accurate architectural segmentation as well as multiplexed molecular imaging to associate molecular phenotypes with relevant cellular and tissue compartments. Multispectral imaging can assist in both these tasks, and conveys new utility to brightfield-based microscopy approaches.

Paget disease of the breast: Changing patterns of incidence, clinical presentation, and treatment in the U.S

BACKGROUND

Paget disease is an uncommon presentation of breast cancer that increased in incidence in the U.S. between 1973 and 1987. Characterized by malignant crusting or ulceration of the nipple, Paget disease can present in 1 of 3 ways: 1) in conjunction with an underlying invasive cancer, 2) in conjunction with underlying ductal carcinoma in situ (DCIS), or 3) alone without any underlying invasive breast carcinoma or DCIS. Paget disease can be treated with breast conservation by undergoing central lumpectomy. The objective of this study was to determine how the incidence, presentation, biomarkers, operative approach, and outcome of Paget disease have evolved in the U.S. since 1988.

METHODS

Between 1988 and 2002, 1738 women who were diagnosed with Paget disease were reported in the 9 registries of the Surveillance, Epidemiology, and End Results Program. To the authors' knowledge, the current study on tumor characteristics, surgical intervention, and survival represented the largest series of Paget disease ever reported.

RESULTS

Although the overall incidence of breast cancer increased between 1988 and 2002, the incidence of Paget disease concomitantly decreased by 45% (95% confidence interval, from -35% to -53%). This decreasing incidence was greatest for Paget disease associated with invasive cancer or DCIS. Invasive cancer associated with Paget disease more commonly was estrogen receptor negative, progesterone receptor negative, and of high histologic grade. Even when 60% of the disease was located centrally, only 293 of 1642 patients with Paget disease (18%) who were treated surgically underwent central lumpectomy. Patients with Paget disease who underwent breast conservation had outcomes equivalent to the outcomes among patients who underwent mastectomy.

CONCLUSIONS

The incidence of Paget disease associated with underlying invasive cancer or DCIS decreased since 1988. Patients who underwent central lumpectomy and patients who underwent mastectomy for Paget disease had similar outcomes; nonetheless, most patients who were candidates for preservation underwent mastectomy.

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.

KAI1/CD82 protein expression in primary prostate cancer and in BPH associated with cancer

Current prognostic methods in primary prostate cancer cannot accurately identify patients with clinically significant disease at highest risk of developing metastases. This study examined KAI1/CD82 metastasis suppressor expression by quantitative immunohistochemical analysis of benign prostatic hyperplasia (BPH) and prostate cancer specimens. Altogether, prostate cancers exhibited significant KAI1 overexpression compared to BPH not associated with cancer (P = 0.022). Increased KAI1 expression in well and moderately differentiated cancers, above levels seen in BPH, with decreased expression in poorly differentiated cancers was observed. Interestingly, KAI1 expression in BPH associated with cancers was significantly higher than in BPH not associated with cancer (P = 0.009). Thus, KAI1 overexpression may restrain onset and early stage prostate cancer development, whilst its loss may predispose the patient to more aggressive cancer behaviour. Altered KAI1 expression in prostate cancers and BPH associated with cancer may have important diagnostic roles.

Intraepidermal cytokeratin 7 immunoreactive cells in the non-neoplastic nipple may represent interepithelial extension of lactiferous duct cells

AIMS

The interpretation of cytokeratin 7 (CK7)-positive cells in the epidermis of the nipple has been controversial. These cells have been described in Paget's disease of the nipple, and they have also been cited as benign 'Toker' cells or as Merkel cells. Having observed CK7+ cells in histologically unremarkable nipple biopsies, we sought to assess the distribution of CK7+ cells in Paget's disease of the nipple and in histologically unremarkable nipple.

METHODS AND RESULTS

Representative sections from 37 cases of Paget's disease of the nipple and 32 cases of histologically unremarkable nipple were obtained. The histologically unremarkable nipple sections were taken from prophylactic mastectomies (n=17) and from autopsies of patients who did not have breast cancer (n=15). CK7 immunostaining was performed on sections from formalin-fixed paraffin blocks. Sequential sections were immunostained with antibodies to low-molecular weight cytokeratin-CAM 5.2 and HER-2/neu. CK7+ cells were present in the epidermis around the opening of the lactiferous ducts in Paget's disease (95%) and in histologically unremarkable nipple (45%) cases. CK7+ cells diminished in number with increasing distance from the orifice of the lactiferous ducts. The lactiferous duct epithelium in Paget's disease and in histologically unremarkable nipple was CK7+ in all specimens when this element was present. CAM5.2 immunostaining had a similar but weaker pattern of reactivity. HER-2/neu reactivity was seen in 68% cases of Paget's disease and was negative in all cases of histologically unremarkable nipple. Tumour cells in two cases of Paget's disease were CK7-. In one of these, the underlying breast carcinoma was also CK7-, the only CK7- tumour in this series. In the other case, the normal lactiferous duct was CK7+ and no underlying carcinomatous tissue was available to study.

CONCLUSIONS

The presence of CK7+ cells does not equate to Paget's disease of the nipple. Intraepidermal CK7+ cells in the non-neoplastic nipple can be a manifestation of interepithelial extension of benign lactiferous duct cells. The increased presence of CK7+ cells in Paget's disease probably results either from neoplastic transformation of native intraepithelial lactiferous duct cells or form direct extension/migration of neoplastic cells into the nipple. The distribution of CK7 immunoreactive cells in the nipple epidermis can be helpful in the diagnosis of Paget's disease of the nipple.

Light and electron microscopy of the pagetoid spread of germ cell carcinoma in the rete testis: morphologic evidence suggestive of field effect as a mechanism of tumor spread

The purpose of this study is to investigate the mechanism of tumor spread in the pagetoid spread of germ cell tumors in the rete testis (PSRT). Twenty consecutive cases of germ cell tumor of the testis (9 seminomas, 3 embryonal carcinomas, and 8 teratocarcinomas) were retrieved to identify the cases with PSRT. The areas of pagetoid spread were examined by the serial sectioning of the entire thickness of the tissue block. Available fresh tissue was submitted for electron microscopic study. Ten cases were associated with PSRT and had focal or extensive areas of intratubular germ cell neoplasia (IGCN) in the proximity of the tumor and the rete testis (RT). In the remaining 10 cases, 6 were associated with IGCN distant from the RT and the last 4 were not associated with IGCN. Seminiferous tubules with IGCN were seen connecting with the RT with pagetoid spread. Isolated single intraepithelial tumor cells also were identified at the periphery of the areas with PSRT. Electron microscopic study of the RT of 4 cases with PSRT (2 seminomas, 1 embryonal carcinoma, and 1 teratocarcinoma) revealed desmosome-type junctions between tumor cells with RT epithelial cells. Direct tumor expansion and cell motility as mechanisms of tumor spread in PSRT does not explain the presence of isolated cells and desmosome-type junctions of the tumor cells as demonstrated in this study. The authors believe that the field effect plays an important part in the pathogenesis of this pagetoid spread in the RT. It is likely that this field effect is induced by the germ cell tumor and is operated through the immature germ cells or undifferentiated epithelial cells in the RT adjacent to the tumor cells.