CDX2 may be a useful marker to distinguish primary ovarian carcinoid from gastrointestinal metastatic carcinoids to the ovary.

Primary ovarian carcinoids and metastatic tumors share similar morphologic features. Metastatic carcinoids must be excluded from primary ones for prognostic and therapeutic reasons. Gastrointestinal neuroendocrine (carcinoid) tumors are much more common with the majority arising from small intestine and appendix. The aim of this study is to evaluate the role of immunohistochemistry for CDX2 in differentiating primary ovarian from metastatic carcinoids of primary gastrointestinal origin. Thirty primary pure ovarian carcinoids, 16 primary ovarian carcinoids arising in association with benign teratomas, 10 ovarian carcinoids metastatic from primary gastrointestinal tract and 70 gastrointestinal neuroendocrine tumors were studied for the expression of CDX2 by immunohistochemistry. CDX2 expression revealed that 40 (57.1%) of 70 cases of gastrointestinal carcinoids and 9 (90%) of 10 ovarian metastatic carcinoids showed positive nuclear staining (diffuse or focal). On the other hand, 3 (18.8%) of 16 primary carcinoids with teratomatous elements showed weak positivity. Among the 70 gastrointestinal carcinoids, CDX2 was positive in 38 (90.5%) of 42 cases in the duodenum, small intestine, appendix, and only in 2 (11.8%) of 17 cases of colorectal carcinoids and none of the 11 cases in the stomach. It is concluded that CDX2 may be a useful marker to distinguish primary ovarian carcinoid from metastasis from small intestinal and appendiceal neuroendocrine tumors.

Pathogenesis of ovarian clear cell adenofibroma, atypical proliferative (borderline) tumor, and carcinoma: clinicopathologic features of tumors with endometriosis or adenofibromatous components support two related pathways of tumor development.

The clinicopathologic features of 472 ovarian epithelial clear cell neoplasms (4 adenofibromas [AFs], 41 atypical proliferative [borderline] tumors [APTs], and 427 carcinomas [CAs]) were studied in order to elucidate the morphologic steps involved in the pathogenesis of these tumors and determine whether clear cell CA is a type I or type II tumor in the dualistic model of ovarian carcinogenesis. Thirty-three percent of the CAs had an adenofibromatous background [CA(AF+)], and 67% did not [CA(AF-)]. Endometriosis was found in all types of tumors, but tumors arising in endometriotic cysts were more frequent with CA(AF-)s (p<0.0001). The subset of women with CA(AF-)s with endometriosis were younger (p<0.0001), their tumors were more frequently cystic (p<0.0001), they more commonly had a mixed carcinoma component of non-clear cell type (p=0.006), and they were more frequently oxyphilic (p=0.015) compared with CA(AF+)s. The architecture of the former tumors was more commonly papillary compared to tubulocystic in the latter (p=0.0006). Atypical endometriosis was more common in CA(AF-)s than in AFs, APTs, and CC(AF+)s [p=0.004]. The subset of CA(AF-)s without endometriosis presented more frequently in advanced stage (>I) and were higher grade compared to CA(AF+)s or CA(AF-) with endometriosis (p-values, <0.0001 to 0.0071). All AFs and APTs were stage I compared to 79% of CA(AF+)s. An increase in mean tumor size correlated with each respective tumor category from AF (6.8 cm) to CA(AF+) [12.9 cm]. Notable nuclear atypia was absent in all AFs but was focally present in 27% of APTs and in the adenofibromatous background of 24% of the CA(AF+)s. An increase in the proportion of carcinoma in the CA(AF+)s correlated with an increase in grade and advanced stage. In summary, ovarian clear cell CA appears to develop along two pathways, both of which are related to endometriosis. We speculate that, in one, epithelial atypia arises in an endometriotic cyst and then evolves into clear cell CA, and, in the other, non-cystic endometriosis induces a fibromatous reaction resulting in the formation of AF, which then develops into APT and subsequently a clear cell CA. The absence of endometriosis or adenofibromatous components in CC(AF-)s may be due to overgrowth and obliteration by the invasive carcinoma. Finally, the findings in this study support the view that both types of clear cell CA [CC(AF+) and CC(AF-)] are more closely related to type I tumors.

Identification of the most sensitive and robust immunohistochemical markers in different categories of ovarian sex cord-stromal tumors.

Different immunohistochemical sex cord-stromal markers have been previously studied in various types of ovarian sex cord-stromal tumors; however, the sensitivity for sex cord-stromal lineage may vary between markers, and some markers may not be as sensitive in some types of sex cord-stromal tumors compared with other tumors in this spectrum of neoplasms. The goals of this study were to determine which immunohistochemical markers are the most sensitive and immunohistochemically robust for sex cord-stromal lineage within a given type of ovarian sex cord-stromal tumor, and to establish whether there are substantial differences of expression of these markers between different types of sex cord-stromal tumors. Immunohistochemical stains for markers which have known variable specificity for sex cord-stromal lineage [inhibin, calretinin, MART-1/melan-A, CD99, steroidogenic factor 1 (SF-1, adrenal 4-binding protein), and WT1], were performed in 127 cases of 5 different types of ovarian sex cord-stromal tumors: adult granulosa cell tumor (n=32), Sertoli cell tumor (n=27), Sertoli-Leydig cell tumor (n=18), steroid cell tumor (n=25), and fibroma/fibrothecoma (n=25). All cases in each type of sex cord-stromal tumor expressed SF-1. Inhibin and calretinin were expressed in all groups of tumors but with a lesser frequency (56% to 100% and 36% to 100% of cases, respectively). All types of tumors except steroid cell tumor expressed WT1. Fibroma/fibrothecoma was the only type of tumor that did not express CD99. The only tumor groups that showed expression of MART-1 were Sertoli-Leydig cell tumor (restricted to the Leydig cell component) and steroid cell tumor (94% and 96% of cases, respectively). The type of sex cord-stromal tumor that was least frequently positive for several of the different markers studied was fibroma/fibrothecoma. Among all tumor groups combined, inhibin and WT1 were the 2 markers showing the most diffuse expression. Likewise, the single marker showing the most optimal combination of diffuse and strong staining (immunohistochemical composite score: possible range, 1 to 12) varied between tumors: adult granulosa cell tumor-inhibin (score 10.0); Sertoli cell tumor-WT1 (score 10.8); Sertoli-Leydig cell tumor (Sertoli cell component)-WT1 (score 10.4); steroid cell tumor-inhibin (score 11.2); and fibroma/fibrothecoma-WT1 (score 8.9). We conclude that most immunohistochemical sex cord-stromal markers have sufficient sensitivity for sex cord-stromal lineage. Although each of the different types of sex cord-stromal tumors has a slightly unique immunoprofile in terms of frequency and extent of expression, these differences are relatively minor for most types of tumors with certain exceptions (eg, WT1 is not diagnostically useful in steroid cell tumor; CD99 is not diagnostically useful in fibroma/fibrothecoma; the only sex cord-stromal tumor for which MART-1 is diagnostically useful is steroid cell tumor; inhibin and calretinin are less diagnostically useful in fibroma/fibrothecoma than in the other types of tumors, but expression in fibrothecoma was higher than in fibroma). SF-1 is the most sensitive sex cord-stromal marker among the most common types of sex cord-stromal tumors. Given the findings relating to sensitivity and extent of expression in this study, and known specificity in the literature, the most informative sex cord-stromal markers to be used for the distinction from nonsex cord-stromal tumors are inhibin, calretinin, SF-1, and WT1 (the exact number of markers to be used should be based on the degree of difficulty of the case and level of experience of the pathologist); however, the utility of immunohistochemistry for the diagnosis of fibroma/fibrothecoma is somewhat limited.

Lupus mastitis: a clinicopathologic review and addition of a case.

Lupus mastitis (LM) is a rare presentation of lupus erythematosus profundus or lupus panniculitis, an unusual and rare clinical variant of lupus erythematosus itself in which the inflammatory reaction occurs primarily in the deep subcutaneous adipose. Although not required for diagnosis, essentially all cases of LM present with systemic or discoid lupus. The etiology is uncertain. Histologically it is defined by a lymphocytic lobular panniculitis and a characteristic hyaline sclerosis of the adipose tissue. Treatment is primarily medical due to exacerbation of disease by surgical intervention. A high index of suspicion, and familiarity of the histologic findings, is therefore required to make an accurate diagnosis and prevent further unwarranted diagnostic procedures. Herein, we provide a literature-based review of the clinical, radiologic, and pathologic findings of LM and its treatment and prognosis with the addition of a case for the literature.

SF-1 is a diagnostically useful immunohistochemical marker and comparable to other sex cord-stromal tumor markers for the differential diagnosis of ovarian sertoli cell tumor.

Immunohistochemistry can be an important part of the diagnosis of Sertoli cell tumor of the ovary, including distinction from non-sex cord-stromal tumors such as the sertoliform variant of endometrioid carcinoma and carcinoid. Several good markers for this differential diagnosis have been identified, particularly inhibin, Wilms tumor 1 gene product (WT1), epithelial membrane antigen, and chromogranin; however, many available markers have limitations to some degree. Steroidogenic factor 1 (SF-1; adrenal 4-binding protein; Ad4BP) is a nuclear transcription factor involved in gonadal and adrenal development. In the testes, SF-1 is expressed in Sertoli cells. Immunohistochemical expression of this marker in ovarian sex cord-stromal tumors, including utility for differential diagnosis, has not been rigorously evaluated. As an extension of our previous immunohistochemical studies of ovarian Sertoli cell tumor, expression of SF-1 and comparison with WT1 and inhibin were assessed in 111 primary ovarian tumors: 27 Sertoli cell tumors, 60 endometrioid tumors (including borderline tumors, conventional well-differentiated carcinomas, and sertoliform variants of carcinoma), and 24 carcinoids. SF-1 was expressed in 100% of Sertoli cell tumors but not in endometrioid tumors or carcinoid. WT1 was expressed in 100% of Sertoli cell tumors and 17% of endometrioid tumors; all carcinoids were negative. Inhibin was expressed in 96% of Sertoli cell tumors and 2% of endometrioid tumors (4% of conventional well-differentiated carcinomas); all carcinoids were negative. The extent of expression of all 3 markers was similar in Sertoli cell tumor but greatest for WT1: 63%, 96%, and 78% of cases showed expression of SF-1, WT1, and inhibin, respectively, in more than 50% of tumor cells. Immunohistochemical composite scores combining both extent and intensity of staining in positive cases were calculated for Sertoli cell tumor (possible range: 1-12). Combined extent/intensity of immunostaining was similar for all 3 markers, but WT1 showed the most robust immunoreactivity in positive cases (mean immunohistochemical composite scores for SF-1, WT1, and inhibin: 6.1, 10.8, and 7.8, respectively). We conclude that for the differential diagnosis with endometrioid tumors and carcinoid of the ovary, SF-1 is a sensitive and specific immunohistochemical marker for Sertoli cell tumor and that SF-1 is diagnostically comparable with other good sex cord-stromal markers.

Cervical biopsy and excision procedure specimens lack sufficient predictive value for lymph-vascular space invasion seen at hysterectomy for cervical cancer.

OBJECTIVE: The purpose of this study was to determine whether lymph-vascular space invasion (LVSI) that is discovered in cervical biopsy and excision specimens is associated with LVSI in the hysterectomy specimen of patients with cervical cancer. STUDY DESIGN: A retrospective pathologic review to determine the presence of LVSI in cervical biopsy specimens, cold-knife cone biopsy (CKC biopsy), and loop electrical excision procedure (LEEP) specimens that contained cervical cancer was performed if subsequent hysterectomy results were available for review. Data were analyzed with chi-square analysis testing. RESULTS: One hundred six patients were identified. The negative predictive value of the biopsy is lower at 0.45 than either the CKC biopsy (0.83) or LEEP (0.57); however, the positive predictive value (0.83) is higher than either CKC biopsy (0.50) or LEEP (0.75). LVSI, when present in cervical biopsy (odds ratio, 4.13; 95% CI, 0.414-98.446), CKC biopsy (odds ratio, 4.8; 95% CI, 0.542-46.280), and LEEP (odds ratio, 4.0; 95% CI, 0.439-43.793) specimens, is associated with a statistically insignificant increased risk of LVSI in the hysterectomy specimen. CONCLUSION: Cervical biopsy and excision specimens lack sufficient negative predictive value for the detection of LVSI in the hysterectomy specimen.

Reversed Expression of the JAK/STAT Pathway Related Proteins Prolactin Receptor and STAT5a in Normal and Abnormal Breast Epithelial Cells.

The JAK/STAT pathway is important for cellular metabolism. One component, STAT5a, is activated in the breast upon prolactin to prolactin receptor (PRLR) binding facilitating the transcription of genes involved in lobule development. STAT5a was previously found to be expressed in most normal breast epithelial cells but not in many in situ or invasive carcinomas except secretory carcinomas which retain STAT5a expression. This report examines the JAK/STAT pathway in the breast through the detection of PRLR and STAT5a. Fifty breast tissues, including benign secretory change, microglandular adenosis, usual and atypical hyperplasia and in situ and invasive ductal carcinoma both usual and secretory, were obtained from the files of the Armed Forces Institute of Pathology. Sections were immunostained with antibodies to PRLR and STAT5a. PRLR was minimally detected on the surface of a few normal breast epithelial cells whereas STAT5a was greatly expressed in over 80% of normal cell nuclei. PRLR was also minimally detected in secretory carcinomas expressing STAT5a. However, the opposite pattern was seen in breast carcinomas lacking STAT5a expression. PRLR was abundantly expressed in these cells. This reversed expression may indicate a JAK/STAT pathway disturbance that could play a role in the initiation or maintenance of an abnormal breast phenotype.

Diagnostic utility of WT1 immunostaining in ovarian sertoli cell tumor.

WT1, the Wilms tumor gene product, can be expressed in various tumors from different anatomic sites, including some types of ovarian tumors. Regarding the latter, most studies have focused on surface epithelial-stromal tumors in which serous carcinomas are usually positive and endometrioid carcinomas are negative. Very few studies have specifically investigated this marker in ovarian sex cord-stromal tumors; however, limited data in the literature suggest that WT1 may be frequently expressed in sex cord-stromal tumors. As pure Sertoli cell tumor can be in the histologic differential diagnosis of endometrioid tumors (particularly borderline tumor and carcinoma) and carcinoid, immunostaining for WT1 might be of diagnostic value. Immunohistochemical staining for WT1 was performed in 108 ovarian tumors: pure Sertoli cell tumor (n=26), endometrioid borderline tumor (n=25), classic well-differentiated endometrioid carcinoma (n=23), sertoliform endometrioid carcinoma (n=12), and carcinoid (n=22). Additionally, inhibin and calretinin immunostaining were performed in all cases of Sertoli cell tumor for purposes of comparing expression with WT1. Extent of immunostaining was scored on a 0 to 4+ semiquantitative scale, and immunohistochemical composite scores based on a combination of extent and intensity of immunostaining were calculated in positive cases (possible range, 1 to 12). Nuclear expression of WT1 was present in 96% of Sertoli cell tumors, 16% of endometrioid borderline tumors, 13% of classic well-differentiated endometrioid carcinomas, 25% of sertoliform endometrioid carcinomas, and 0% of carcinoids. In Sertoli cell tumors, expression was diffuse (>50% of positive cells) in all positive cases. When positive in the non-Sertoli cell tumors, the extent of expression tended to be focal to patchy (50% or less positive cells). In Sertoli cell tumors, inhibin and calretinin were expressed in 96% and 54% of cases, respectively. The extent of expression of inhibin tended to be diffuse, similar to WT1; however, the extent of immunostaining for calretinin tended to be focal to patchy. The immunohistochemical composite scores for WT1, inhibin, and calretinin were 11.2, 7.6, and 4.8, respectively. Coordinate patterns for the extent of expression of WT1, inhibin, and calretinin in pure Sertoli cell tumor showed that all 3 markers were positive in 54% of cases; however, 42% were positive for WT1 and inhibin but negative for calretinin. In cases positive for both WT1 and inhibin, expression of both markers was diffuse in 84% of cases, but WT1 was diffuse while inhibin was focal to patchy in 16% of cases. We conclude that ovarian Sertoli cell tumor should be added to the growing list of WT1-positive tumors. This marker is useful for the distinction of Sertoli cell tumor from endometrioid tumors and carcinoid. The diagnostic utility of WT1 in Sertoli cell tumor is similar to inhibin but better than that of calretinin.

Immunohistochemical analysis of sox9 in ovarian Sertoli cell tumors and other tumors in the differential diagnosis.

The distinction of ovarian Sertoli cell tumor from other tumors in the histological differential diagnosis, particularly endometrioid carcinoma and carcinoid tumor, may be difficult. Many immunohistochemical markers have been studied for this differential diagnosis, but currently available markers are neither 100% sensitive nor specific. Sox9 is a transcription factor involved in Sertoli cell differentiation in the testis. The role that this molecule plays in the pathogenesis of ovarian Sertoli cell tumors and the potential use as an immunohistochemical marker for differential diagnosis have not been investigated. Immunohistochemical staining for Sox9 was performed in 152 ovarian tumors: pure Sertoli cell tumor (n = 36), endometrioid borderline tumor (n = 38), well-differentiated endometrioid carcinoma (n = 26), sertoliform endometrioid carcinoma (n = 13), and carcinoid tumor (n = 39). Nuclear expression was considered positive. Extent and intensity of staining were semiquantitatively scored. In addition, immunohistochemical composite scores in positive cases (ranging from 1 to 12) were calculated based on the extent score multiplied by the intensity score. Sox9 was expressed in 44% of Sertoli cell tumors, 55% of endometrioid borderline tumors, 65% of well-differentiated endometrioid carcinomas, 39% of sertoliform endometrioid carcinomas, and 10% of carcinoid tumors. The mean Sox9 immunohistochemical composite scores in positive cases were 6.3 for Sertoli cell tumor, 5.3 for endometrioid borderline tumor, 8.0 for well-differentiated endometrioid carcinoma, 2.8 for sertoliform endometrioid carcinoma, and 6.8 for carcinoid tumor. The differences in the mean Sox9 composite scores between Sertoli cell tumor and the other tumor categories were not statistically significant (p values ranged from 0.092 to 0.523). We conclude that Sox9 is variably expressed in ovarian Sertoli cell tumor and other tumors that are in the differential diagnosis and, thus, is not helpful for immunohistochemical distinction. Understanding the role of Sox9 in the pathogenesis of ovarian Sertoli cell tumor requires further study.

Comparative analysis of alternative and traditional immunohistochemical markers for the distinction of ovarian sertoli cell tumor from endometrioid tumors and carcinoid tumor: A study of 160 cases.

The main neoplasms in the differential diagnosis for primary ovarian tumors with a tubule-rich pattern are pure Sertoli cell tumor, endometrioid tumors (including borderline tumor, well-differentiated carcinoma, and the sertoliform variant of endometrioid carcinoma), and carcinoid tumor. Because traditional immunohistochemical markers [pan-cytokeratin (pan-CK), low molecular weight cytokeratin (CK8/18), epithelial membrane antigen (EMA), inhibin, calretinin, CD99, chromogranin, and synaptophysin] can occasionally have diagnostic limitations, the goal of this study was to determine whether or not any alternative markers [cytokeratin 7 (CK7), estrogen receptor (ER), progesterone receptor (PR), CD10, and CD56] have better diagnostic utility when compared with traditional markers for this differential diagnosis. Immunohistochemical stains for alternative, as well as traditional, markers were performed on the following primary ovarian tumors: pure Sertoli cell tumor (n = 40), endometrioid borderline tumor (n = 38), sertoliform endometrioid carcinoma (n = 13), well-differentiated endometrioid carcinoma (n = 27), and carcinoid tumor (n = 42). Extent and intensity of immunostaining were semiquantitatively scored. In addition, immunohistochemical composite scores (ICSs) in positive cases were calculated on the basis of the combination of extent and intensity scores. Cytokeratin 7 (CK7) was positive in 97% of endometrioid tumors, 13% of Sertoli cell tumors, and 24% of carcinoid tumors. The differences in the mean ICSs for endometrioid tumors versus Sertoli cell tumor or carcinoid tumor were statistically significant (P values ranging from <0.001 to 0.018). ER and PR were positive in 87% and 86% of endometrioid tumors, 8% and 13% of Sertoli cell tumors, and 2% each of carcinoid tumors, respectively. The differences in the mean ICSs for endometrioid tumors versus Sertoli cell tumor were statistically significant (P values ranging from <0.001 to 0.012). Among the epithelial markers, EMA seemed to be the most discriminatory but only slightly better than CK7, ER, or PR. Pan-CK and CK8/18 were not helpful. CD10 showed overlapping patterns of expression in all categories of tumors. Among the sex cord markers, CD10 was markedly less useful than inhibin or calretinin; CD99 was not discriminatory. CD56 showed overlapping patterns of expression in all categories of tumors. Among the neuroendocrine markers, CD56 was less useful than chromogranin or synaptophysin. When traditional immunohistochemical markers are problematic for the differential diagnosis of ovarian Sertoli cell tumor versus endometrioid tumors versus carcinoid tumor, adding CK7, ER, and/or PR to a panel of markers can be helpful. Endometrioid tumors more frequently express CK7, ER, and PR and show a greater extent of immunostaining in contrast to Sertoli cell tumor and carcinoid tumor. Compared with traditional epithelial markers, CK7, ER, and PR are nearly as advantageous as EMA. Inhibin is the most discriminatory sex cord marker, and CD10 is not helpful in the differential diagnosis. Chromogranin and synaptophysin are excellent discriminatory markers for carcinoid tumor, and CD56 is neither sufficiently sensitive nor specific enough for this differential diagnosis to warrant its use in routine practice.

Pseudoinfiltrative tubal metaplasia of the endocervix: a potential form of in utero diethylstilbestrol exposure-related adenosis simulating minimal deviation adenocarcinoma.

We report three cases of unusual tubal-type endocervical glandular proliferations simulating minimal deviation adenocarcinoma in women with a history of in utero diethylstilbestrol (DES) exposure. The lesions were characterized by haphazard glandular proliferations extending from 3.4 to 6.1 mm into the endocervical stroma and to the margins of excision in all cases. Most of the glands were small to medium-sized and round; some exhibited a moderate degree of cystic dilatation, and occasional glands had curvilinear profiles. The glandular epithelium displayed extensive tubal-type differentiation in all cases. In two cases, the glands lacked cytologic atypia and mitotic activity, and in one case, there was mild to moderate nuclear atypia with occasional mitotic activity. Immunohistochemical studies showed diffuse expression of estrogen and progesterone receptors and essentially no expression of p16 in two cases tested; there was no expression of CD10 in one case that was tested. The Ki-67 proliferation index was zero in one case and 25% in another. Human papillomavirus DNA was not detected by in situ hybridization in one case that was tested. The proliferations lacked features of mucinous and tubo-endometrioid types of minimal deviation adenocarcinoma. The clinicopathologic findings suggest the lesions are benign, and the association with in utero DES exposure raises the possibility that these could be a form of DES-related adenosis.

Immunohistochemical staining for Ki-67 and p53 helps distinguish endometrial Arias-Stella reaction from high-grade carcinoma, including clear cell carcinoma.

The distinction of the Arias-Stella reaction from clear cell carcinoma of the endometrium is usually straightforward; however, this differential diagnosis can be difficult when the Arias-Stella reaction occurs outside the setting of pregnancy or in older patients. The differential diagnosis also is problematic when serous or clear cell carcinoma focally arises within an endometrial polyp, as part of "endometrial intra-epithelial carcinoma" (EIC), or in younger patients. The goal of this study was to determine whether immunohistochemical staining can distinguish the Arias-Stella reaction from endometrial high-grade carcinoma, particularly clear cell carcinoma. Cases of endometrial Arias-Stella reaction (n = 27), clear cell carcinoma (n = 11), serous carcinoma (n = 7), and EIC (n = 4) were assessed by immunohistochemical staining with antibodies for Ki-67, p53, estrogen receptor (ER), and progesterone receptor (PR). Composite immunohistochemical scores based on the percentage and intensity of stained cells were calculated, as was the overall positivity (percentage positive cases), using a cutoff value of >/=5% stained cells and at least weak intensity. Appropriate statistical tests were performed. Ki-67 and p53 immunostaining was significantly less in Arias-Stella reaction than in clear cell carcinoma (p < 0.0001 for both) or serous carcinoma/EIC (p < 0.0001 for both), measured by the composite immunohistochemical scores or overall positivity. ER showed a significant difference only between Arias-Stella reaction and clear cell carcinoma; PR showed a significant difference only between Arias-Stella reaction and serous carcinoma/EIC. When clinical or histologic features cannot facilitate the differential diagnosis, immunohistochemical staining for Ki-67 and p53 may help distinguish endometrial Arias-Stella reaction from clear cell carcinoma and other types of high-grade carcinoma.

Cell clusters overlying focally disrupted mammary myoepithelial cell layers and adjacent cells within the same duct display different immunohistochemical and genetic features: implications for tumor progression and invasion.

INTRODUCTION: Our previous studies detected focal disruptions in myoepithelial cell layers of several ducts with carcinoma in situ. The cell cluster overlying each of the myoepithelial disruptions showed a marked reduction in or a total loss of immunoreactivity for the estrogen receptor (ER). This is in contrast to the adjacent cells within the same duct, which were strongly immunoreactive for the ER. The current study attempts to confirm and expand previous observations on a larger scale. METHODS: Paraffin sections from 220 patients with ER-positive intraductal breast tumors were double immunostained with the same protocol previously used. Cross-sections of ducts lined by > or = 40 epithelial cells were examined for myoepithelial cell layer disruptions and for ER expression. In five selected cases, ER-negative cells overlying the disrupted myoepithelial cell layer and adjacent ER-positive cells within the same duct were separately microdissected and assessed for loss of heterozygosity and microsatellite instability. RESULTS: Of the 220 cases with 5698 duct cross-sections examined, 94 showed disrupted myoepithelial cell layers with 405 focal disruptions. Of the 94 cases, 79 (84%) contained only ER-negative cell clusters, nine (9.6%) contained both ER-negative and ER-positive cell clusters, and six (6.4%) contained only ER-positive cell clusters overlying disrupted myoepithelial cell layers. Of the 405 disruptions, 350 (86.4%) were overlain by ER-negative cell clusters and 55 (13.6%) were overlain by ER-positive cell clusters (P < 0.01). Microdissected ER-negative and ER-positive cells within the same duct from all five selected cases displayed a different frequency or pattern of loss of heterozygosity and/or microsatellite instability at 10 of the 15 DNA markers. CONCLUSIONS: Cells overlying focally disrupted myoepithelial layers and their adjacent counterparts within the same duct displayed different immunohistochemical and molecular features. These features potentially represent an early sign of the formation of a biologically more aggressive cell clone and the myoepithelial cell layer breakdown possibly associated with tumor progression or invasion.

A subset of morphologically distinct mammary myoepithelial cells lacks corresponding immunophenotypic markers.

INTRODUCTION: Immunostaining for smooth muscle actin (SMA) is commonly used to elucidate mammary myoepithelial (ME) cells, whose presence or absence is a reliable criterion for differentiating in situ and invasive carcinomas. However, some morphologically distinct ME cells fail to stain for SMA. This study intended to assess whether these SMA-negative cells also lack the expression of other ME cell markers. METHODS: Hematoxylin/eosin and SMA immunostained sections from 175 breast cancer patients were examined. Three cases were found to harbor ducts that showed morphologically distinct ME cell layers, but showed no SMA immunostaining in at least one-third of the layer or the entire layer. Eight additional consecutive sections from each case were stained for SMA, using a black chromogen, and each was then re-stained for one of eight additional markers supposed to exclusively or preferentially stain ME cells, using a red chromogen. SMA-negative ME cells were re-examined for the expression of other markers. RESULTS: SMA-negative ME cells in two cases also failed to display immunoreactivity for other markers, including calponin, CD10, smooth muscle myosin heavy chain, protease inhibitor 5 (maspin), Wilms' tumor-1, and cytokeratins 5, 14, and 17 (CK5, CK14, and CK17). However, in one case SMA-negative ME cells displayed immunoreactivities for maspin, CK5, CK14, and CK17. The distribution of these ME cells is independent of ductal size, length, and architecture. CONCLUSIONS: A subset of morphologically identifiable ME cells lack the expression of nine corresponding immunophenotypic markers, suggesting that ME cells might also be subject to different normal and pathological alterations.