Antigenic profile of mammary fibroadenoma and cystosarcoma phyllodes. A study using antibodies to estrogen- and progesterone receptors and to a panel of cell surface molecules

A Diagnostic Approach to Fibroepithelial Breast Lesions

Fibroepithelial breast lesions encompass a heterogeneous group of neoplasms that range from benign to malignant, each exhibiting differing degrees of stromal proliferation in relation to the epithelial compartment. Fibroadenomas are common benign neoplasms that may be treated conservatively. Phyllodes tumors are relatively rare lesions, and classified as benign, borderline, or malignant based on histologic evaluation of various parameters. The diagnostic interpretation of "gray-zone" fibroepithelial lesions often imposes formidable demands on a pathologist's skills. This article offers practical recommendations for the diagnostic workup of these lesions, including the appropriate utilization of ancillary investigations and the approach to core needle biopsies.

Phyllodes tumours of the breast: a consensus review

Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Accurate and reproducible grading of these tumours has long been challenging, owing to the need to assess multiple stratified histological parameters, which may be weighted differently by individual pathologists. Distinction of benign phyllodes tumours from cellular fibroadenomas is fraught with difficulty, due to overlapping microscopic features. Similarly, separation of the malignant phyllodes tumour from spindle cell metaplastic carcinoma and primary breast sarcoma can be problematic. Phyllodes tumours are treated by surgical excision. However, there is no consensus on the definition of an appropriate surgical margin to ensure completeness of excision and reduction of recurrence risk. Interpretive subjectivity, overlapping histological diagnostic criteria, suboptimal correlation between histological classification and clinical behaviour and the lack of robust molecular predictors of outcome make further investigation of the pathogenesis of these fascinating tumours a matter of active research. This review consolidates the current understanding of their pathobiology and clinical behaviour, and includes proposals for a rational approach to the classification and management of phyllodes tumours.

Use of CD10 as a marker of canine mammary myoepithelial cells

CD10 is an important cell marker in the diagnosis of acute lymphoblastic leukaemia and of breast myoepithelial (ME) cells in humans. The objective of this study was to assess the value of CD10 as a marker of canine ME cells using immunohistochemistry on routinely processed normal, dysplastic and neoplastic mammary tissue. Five different CD10 positive cell types were identified on the basis of cell morphology, pattern of immunoreactivity, and on the co-expression of additional cell lineage-specific markers. Type 1 cells were typical fusiform cells with a ME cell phenotype (calponin- and cytokeratin [CK] 14-positive, CK8/18-negative). Type 2 cells were typical or atypical polyhedral cells with a luminal epithelial (LE) cell phenotype (calponin- and CK14-negative, CK8/18-positive). Type 3 cells had a type 1 phenotype with variable morphology, and type 4 were atypical neoplastic cells with a mixed ME/LE phenotype. Type 5 cells were typical fusiform cells with a stromal phenotype. Type 1 cells were considered normal ME cells and were found in all sample types; type 2 cells were considered normal or neoplastic LE cells and were also found in all sample types; types 3 and 4 cells were restricted to tumour samples and to malignant tumours, respectively, and type 5 cells were found in all sample types, although predominantly in neoplastic tissue. The findings indicate that the CD10 antigen is a sensitive (although not specific) marker of canine ME cells in normal, dysplastic and neoplastic mammary tissue. Differences in the distribution and staining intensity of CD10-positive cells suggest a number of potential roles for this protein in the pathogenesis of canine mammary neoplasia.

Cell polarity proteins: common targets for tumorigenic human viruses

Loss of polarity and disruption of cell junctions are common features of epithelial-derived cancer cells, and mounting evidence indicates that such defects have a direct function in the pathology of cancer. Supporting this idea, results with several different human tumor viruses indicate that their oncogenic potential depends in part on a common ability to inactivate key cell polarity proteins. For example, adenovirus (Ad) type 9 is unique among human Ads by causing exclusively estrogen-dependent mammary tumors in experimental animals and in having E4 region-encoded open reading frame 1 (E4-ORF1) as its primary oncogenic determinant. The 125-residue E4-ORF1 protein consists of two separate protein-interaction elements, one of which defines a PDZ domain-binding motif (PBM) required for E4-ORF1 to induce both cellular transformation in vitro and tumorigenesis in vivo. Most notably, the E4-ORF1 PBM mediates interactions with a selected group of cellular PDZ proteins, three of which include the cell polarity proteins Dlg1, PATJ and ZO-2. Data further indicate that these interactions promote disruption of cell junctions and a loss of cell polarity. In addition, one or more of the E4-ORF1-interacting cell polarity proteins, as well as the cell polarity protein Scribble, are common targets for the high-risk human papillomavirus (HPV) E6 or human T-cell leukemia virus type 1 (HTLV-1) Tax oncoproteins. Underscoring the significance of these observations, in humans, high-risk HPV and HTLV-1 are causative agents for cervical cancer and adult T-cell leukemia, respectively. Consequently, human tumor viruses should serve as powerful tools for deciphering mechanisms whereby disruption of cell junctions and loss of cell polarity contribute to the development of many human cancers. This review article discusses evidence supporting this hypothesis, with an emphasis on the human Ad E4-ORF1 oncoprotein.

Estrogen receptor-beta is expressed in stromal cells of fibroadenoma and phyllodes tumors of the breast

An estrogen dependency has been suggested for the growth of fibroadenomas: however, thus far, none of the steroid hormone receptors acting on breast tissues has been demonstrated in the stroma of breast fibroepithelial lesions. In this study, the expression of estrogen receptor (ER)-alpha and -beta was investigated by immunohistochemistry in 33 fibroadenomas and in 30 benign, three borderline and seven malignant phyllodes tumors, all with spindle cell growth and in one distant metastasis. In addition, the presence of ER-beta mRNA and its variants was evaluated by RT-PCR in microdissected stroma. The possible correlation between hormone receptor expression and differentiation processes of stromal cells was investigated by smooth muscle actin and calponin immunostaining. ER-beta was the only hormone receptor expressed by stroma of fibroadenomas and phyllodes tumors, both at protein and mRNA level. The highest percentage of ER-beta was observed in fibroadenomas with cellular stroma and in phyllodes tumors. In both lesions, ER-beta-positive stromal cells showed expression of smooth muscle actin and/or calponin, as demonstrated by double immunostaining. In addition, the mean age at diagnosis was significantly lower in patients with ER-beta-positive vs ER-beta-negative fibroadenomas. In contrast, in phyllodes tumors, ER-beta expression was higher in older patients. In conclusion, (i) only ER-beta is detected in the stroma of fibroadenomas and phyllodes tumors; (ii) its expression correlates with the expression of smooth muscle markers and suggests a role of ER-beta in myofibroblastic differentiation of stromal cells. These two results, together with the young age of patients carrying fibroadenomas with highly ER-beta-positive stroma cells, may further indicate a hormone-receptor mechanism involved in regulating the growth of fibroadenomas. Conversely, the older age of patients with ER-beta-rich phyllodes tumors suggests that mechanisms, probably independent from estrogen stimulation, act on the growth of these tumors.

Ber-H2 (CD30) immunohistochemical staining of human fetal tissues

OBJECTIVE: CD30 antigen has long been considered to be restricted to the tumour cells of Hodgkin's disease and of anaplastic large cell lymphoma as well as to T and B activated lymphocytes. It is now apparent that the range of normal and neoplastic cells, which may express CD30 antigen, is much wider than was at first thought. In order to gain insight into the physiological function of CD30 antigen, we studied the distribution of its expression in the tissues of fetuses from week 8^th to week 16^th.

MATERIALS AND METHODS: We investigated the immunohistochemical expression of CD30 antigen in paraffin-embedded tissue samples representing all systems from 30 fetuses after therapeutic abortion at 8^th to 10^th and 12^th to 16^th week of gestation, respectively, using the monoclonal antibody Ber-H2.

RESULTS: Our results demonstrated that CD30 is expressed early in human fetal development (8^th to 10^th week of gestation) in several fetal tissues derived from all three germ layers (gastrointestinal tract, special glands of the postpharyngeal foregut, urinary, musculoskeletal, reproductive, nervous, endocrine systems), with the exception of the skin and hematolymphoid system (thymus), in which the antigen is expressed later on (10^th week onwards). Expression of CD30 was restricted to the hematolymphoid system in the 12-16 weeks of gestation. No expression of the marker was observed in the respiratory and cardiovascular systems during the entire period examined.

CONCLUSIONS: CD30 antigen is of importance in cell development, and proliferation. It is also pathway-related to terminal differentiation in many fetal tissues and organs.

Stromal CD10 expression in mammary fibroadenomas and phyllodes tumours

BACKGROUND/AIMS

CD10 (CALLA) has recently been reported to be expressed in spindle cell neoplasia, and has been used to differentiate endometrial stromal sarcoma from leiomyoma and leiomyosarcoma. In the breast, myoepithelial cells express CD10, but there are few studies of the expression of CD10 in mammary fibroepithelial lesions.

METHODS

Stromal CD10 expression was studied in 181 mammary phyllodes tumours (102 benign, 51 borderline malignant, and 28 frankly malignant) and 33 fibroadenomas using immunohistochemistry, to evaluate whether differences in expression correlated with the degree of malignancy.

RESULTS

There was a progressive increase in the patients' age and tumour size, from fibroadenoma to phyllodes tumours with an increasing degree of malignancy (p < 0.001). Stromal CD10 expression was positive in one of 33 fibroadenomas, six of 102 benign phyllodes tumours, 16 of 51 borderline malignant phyllodes tumours, and 14 of 28 frankly malignant phyllodes tumours. The difference was significant (p < 0.001) and an increasing trend was established. Strong staining was seen in subepithelial areas with higher stromal cellularity and activity. Stromal CD10 expression had a high specificity (95%) for differentiating between benign lesions (fibroadenomas and benign phyllodes tumours) and malignant (borderline and frankly malignant) phyllodes tumours.

CONCLUSIONS

CD10 may be a useful adjunct in assessing malignancy in mammary fibroepithelial lesions.

Human embryonal epithelial cells of the developing small intestinal crypts can express the Hodgkin-cell associated antigen Ki-1 (CD30) in spontaneous abortions during the first trimester of gestation

BACKGROUND

Ki-1 (CD30) antigen expression is not found on peripheral blood cells but its expression can be induced in vitro on T and B lymphocytes by viruses and lectins. Expression of CD30 in normal tissues is very limited, being restricted mainly to a subpopulation of large lymphoid cells; in particular, cells of the recently described anaplastic large cell lymphoma (ALCL), the Reed-Sternberg (RS) cells of Hodgkin's lymphoma and scattered large parafollicular cells in normal lymphoid tissues. More recent reports have described CD30 expression in non-hematopoietic and malignant cells such as cultured human macrophages, human decidual cells, histiocytic neoplastic cells, mesothelioma cells, embryonal carcinoma and seminoma cells.

RESULTS

We investigated the immunohistochemical expression of CD30 antigen in 15 paraffin-embedded tissue samples representing small intestines from fetuses after spontaneous abortion in the 8th, 10th and 12th weeks using the monoclonal antibody Ki-1. Hormones had been administered to all our pregnant women to support gestation. In addition, a panel of monoclonal antibodies was used to identify leukocytes (CD45/LCA), B-lymphocytes (CD20/L-26) and T-lymphocytes (CD3). Our findings were correlated with those obtained simultaneously from intestinal tissue samples obtained from 15 fetuses after therapeutic or voluntary abortions.

CONCLUSIONS

The results showed that: (1) epithelial cells in the developing intestinal crypts express the CD30 (Ki-1) antigen; (2) CD30 expression in these epithelial cells is higher in cases of hormonal administration than in normal gestation. In the former cases (hormonal support of gestation) a mild mononuclear intraepithelial infiltrate composed of CD3 (T-marker)-positive cells accompanies the CD30-positive cells.

Phyllodes tumor of the seminal vesicle: Case report and literature review

A 39-year-old man presented with urinary retention and lower abdominal discomfort at our hospital, and a computed tomography scan showed a huge cystic mass posterior to the urinary bladder. During surgical exploration, a mass superior to the prostate in the region of the left seminal vesicle was found. Histologically, the tumor was characterized by cystically dilated or slit-like glands mixed in a densely cellular stroma with pleomorphism and resembled those of phyllodes tumor of the breast or prostate. The glandular epithelium within the tumor showed focal lipofuscin pigment and negative staining for prostate specific antigen (PSA). The stromal cells showed positive immunoreactivity for vimentin and CD34, and focal positive reactions for desmin and alpha-smooth muscle actin. Mitosis was present 0 to 1 per 10 high power fields of magnification in the stromal cells. Approximately 20% of the stromal cells were positive for progesterone receptor. The patient is alive with no evidence of disease 12 months after surgery. Mixed epithelial-stromal tumors of the seminal vesicle are extremely rare. A combination of stromal cellularity, atypia and mitosis might be used for the histological grading, and a prostatic origin might be excluded by the location of the primary lesion itself and by the failure to show PSA.

Clinicopathologic evaluation of CDw75 antigen expression in colorectal adenocarcinomas

CDw75, a B lymphocyte surface antigen, is a sialylated carbohydrate epitope, which is generated by the enzyme beta galactosyl alpha 2,6 sialyltransferase (Sia-T1). In colon carcinomas, although higher levels of Sia-T1 has been described and found to be correlated with metastatic potential of tumor cells, the expression of CDw75 antigen still remains unknown. To address this issue, we investigated immunohistochemically CDw75 antigen expression in 195 colorectal adenocarcinomas and their nodal metastases. The correlation between CDw75 antigen expression with selected clinicopathologic variables was analyzed by using Chi-square and Fisher s exact tests. Positive staining was observed in 101 cases. Non-neoplastic mucosa was negative consistently. The frequency of positivity was decreased according to the degree of differentiation (p<0.001). Antigen expression was found to be associated with deeper penetration (p<0.006), positive lymph nodes (p<0.001), distant metastases (p<0.006) and advanced stage (p<0.001). Same relationships were detected in well and moderately differentiated tumors when CDw75 immunoreactivity was evaluated in each histologic grade separately. Our findings indicate that CDw75 antigen expression may be a good indicator of the biological aggressiveness of colorectal adenocarcinomas especially in tumors with well and moderately differentiated morphology.

Hormonal receptors expression in epithelial cells of mammary phyllodes tumors correlates with pathologic grade of the tumor: a multicenter study of 143 cases

We used immunohistochemical analysis to detect the presence of estrogen receptor (ER), progesterone receptor (PR), and androgen receptor (AR) protein expression in the epithelial and stromal cells of 143 phyllodes tumors (PTs). Expression of epithelial ER and PR proteins was common, occurring in 43% to 84% of PTs. Expression of epithelial AR protein and stromal ER, PR, and AR proteins was low (5% or less) in all tumors. An inverse relationship of epithelial ER and PR protein expression with degree of malignancy in PT was found (P < .05), and ER expression also correlated with mitotic count (P < .05). When considering PT with the expression of ER or PR proteins and the coexpression of both, the inverse relationship with tumor grade also was significant (P < .05). As the hormonal receptor protein expression shows a consistent decrease with increasing malignancy, we infer that the epithelium has a crucial role in the pathogenesis or progression of PT.

Availability of CD10 immunohistochemistry as a marker of breast myoepithelial cells on paraffin sections

CD10, also called common acute lymphoblastic leukemia antigen (CALLA), was recently found to be expressed in nonhematopoietic tissues. Although CD10 was also identified in human breast myoepithelial cells, its availability of immunohistochemistry on paraffin sections has not been examined so far. In the present study, we demonstrated CD10 immunohistochemically on paraffin sections of both normal and pathological breast tissues, comparing its staining patterns to those of smooth muscle actin (SMA), which is now commonly used to highlight myoepithelium. CD10 was consistently positive in normal breast myoepithelial cells. CD10 also clearly highlighted myoepithelial cells in intraductal papilloma, adenosis, ductal hyperplasia, fibroadenoma, and phyllodes tumor as well as SMA did. In atypical ductal hyperplasia and ductal carcinoma in situ, continuous, discontinuous, and totally negative stainings of both CD10 and SMA were noted, depending on foci of neoplastic cell nests. However, both stainings clearly demonstrated myoepithelial cells of cancerized acini, being useful in differentiating lobular cancerization from microinvasion. Because SMA was also positive in normal vessels and spindle-shaped stromal cells, CD10, which was negative in vessels, was useful in differentiating myoepithelial cells from thin vascular wall in intracystic lesions with delicate papillae. Although background staining of spindle-shaped stromal cells was also noted in CD10, the positive cell number was less, and the signal was weaker than that of SMA. The absence of myoepithelial cells in invasive ductal carcinomas was more clearly highlighted by CD10 than SMA. We concluded that CD10 could be another useful marker of breast myoepithelial cells on paraffin sections. Combination of CD10 and SMA will provide more sophisticated information about presence or absence of myoepithelial cells in confusing breast lesions.

Clinicopathologic evaluation of CDw75 antigen expression in patients with gastric carcinoma

Situated on mature B lymphocytes, CDw75 antigen is a sialylated carbohydrate epitope generated by the enzyme beta-galactosyl alpha-2,6-sialyltransferase. Although CDw75 antigen expression was found to be correlated with aggressive behaviour of tumour cells in gastric adenocarcinomas, its prognostic role still remains unknown. The objective of this study was to determine the value of CDw75 antigen expression as a marker of the metastatic potential and prognosis of gastric adenocarcinomas. CDw75 antigen expression was evaluated immunohistochemically in 64 tumours and their nodal metastases. The correlation was analysed between CDw75 antigen expression and selected clinicopathological variables, including survival. Positive staining was detected in 31 cases. Non-neoplastic gastric mucosa was consistently negative. CDw75 expression was correlated with larger tumour size (p<0.006), infiltrative growth pattern (p<0.044), advanced stage (p<0.0006), and positive lymph nodes (p<0.0003). The overall survival rate of patients with CDw75 expression was 28%, which was significantly worse than that of patients without CDw75 expression (53%) (p<0.0005). Multivariate analysis showed that CDw75 expression was an independent prognostic indicator, together with the growth pattern of the tumour. These results indicate that immunohistochemical detection of CDw75 antigen expression may be a good indicator of metastatic potential and of prognosis in patients with gastric carcinomas.

Expression of the CD30 antigen in non-lymphoid tissues and cells

Originally, expression of the CD30 antigen was shown to be typical of the tumour cells of Hodgkin's disease (HD) and of anaplastic large cell lymphomas (ALCLs). In reactive lymphoid tissue, CD30 is expressed only in a small population of activated lymphoid blasts. Since then, several reports have been published describing CD30 expression in non-lymphoid tissues and malignancies, such as embryonal carcinomas (ECs), seminomas, cultivated macrophages, two histiocytic neoplasms, decidual cells, and mesotheliomas. As CD30 detection is important in the differential diagnosis of HD and ALCL, the expression of CD30 in different non-lymphoid tissues was re-evaluated by immunohistology and in situ hybridization. Extra-lymphoid CD30 expression was found in 48/51 cases of EC or EC components of germ cell tumours, in decidual cells of 1/10 cases, in activated mesothelium in 16/28 pleural and peritoneal effusions, and in small foci of tumour cells in 2/8 mesotheliomas. CD30 expression was not confirmed in 27 germ cell tumours of the testis without an EC component nor in cultivated macrophages and 17 histiocytic malignancies. The knowledge of these CD30 expression patterns is important for the immunohistological differential diagnosis of anaplastic tumours. The absence of CD30 expression in reactive and neoplastic macrophages does not favour the concept that HD and ALCL are derived from these cells.

p53 expression in phyllodes tumours is associated with histological features of malignancy but does not predict outcome

AIMS

To study p53 protein expression in phyllodes tumours of the breast, with particular attention to its prevalence and to its relationship with histological features and clinical outcome.

METHODS AND RESULTS

Stromal and epithelial p53 immunohistochemical expression was studied in 57 phyllodes tumours (27 benign, 17 borderline, 13 malignant) using an avidin-biotin peroxidase method. High levels of expression (> 30% of stromal nuclei) were found in eight phyllodes tumours (14%). p53 expression was associated with tumour grade (P = 0.001), prominent stromal overgrowth (P = 0.0003), prominent stromal nuclear pleomorphism (P = 0.006), high stromal mitotic count (P = 0.05), and an infiltrative tumour margin (P = 0. 05). Six patients were lost to follow-up after surgery. Mean follow-up time of the remaining 51 patients was 7.3 years (median 4. 3, range 0.5-25) or until death. Sixteen patients (31%) experienced tumour recurrence. Recurrence was more likely if there was an infiltrative tumour margin (P = 0.006) or prominent stromal overgrowth (P = 0.04) but not p53 expression (P = 0.55). A minority of recurrences expressed p53 more extensively than their primary counterparts. There were five tumour-related deaths (10% of patients). Death was associated with high grade (P = 0.0002), prominent stromal overgrowth (P = 0.0001), an infiltrative margin (P = 0.0002), prominent nuclear pleomorphism (P = 0.005), a high mitotic count (P = 0.01) and tumour size (P = 0.03). Again, p53 expression was not associated with tumour-related survival (P = 0. 13).

CONCLUSIONS

p53 abnormalities occur in a minority of borderline and malignant phyllodes tumours. p53 expression is associated with known negative prognostic factors, but does not appear to be a useful determinant of tumour recurrence or long-term survival.

Malignant phyllodes tumor of the breast with hypoglycemia: report of a case

A surgically resected case of giant malignant phyllodes tumor of the breast associated with a hypoglycemic attack is reported. A 54-year-old woman was referred to our hospital with loss of consciousness and a huge chest wall tumor. She was diagnosed as having a malignant phyllodes tumor by core needle biopsy and underwent palliative simple mastectomy because lung metastasis was detected on computed tomography and by other imaging modalities on admission. The preoperative laboratory data revealed a very low fasting blood sugar level of 37 mg/dl. After removal of the tumor, the blood sugar level gradually normalized (90-100 mg/dl) and the plasma insulin-like growth factor-II (IGF-II) level promptly decreased. The IGF-II level of tumor extracts was high (2500 ng/g wet weight) and the majority of atypical cells stained positively for IGF-II immunohistochemically. These findings suggested that the patient's hypoglycemia was associated with IGF-II produced by a giant malignant phyllodes tumor that consumed glucose.

Mammary tumors induced by human adenovirus type 9: a role for the viral early region 4 gene

Human adenovirus type 9 (Ad9) elicits exclusively estrogen-dependent mammary tumors when injected into female rats. Three different histological types of mammary tumor (benign fibroadenomas, phyllodes tumors, and malignant solid sarcomas) have been described in Ad9-infected animals, with benign fibroadenomas being seen most frequently. Interestingly, in contrast to other adenoviruses, in which oncogenic viral functions are entirely encoded within the E1 region, Ad9 requires an E4 region transforming protein (ORF1) for its unique mammary oncogenicity. Studies of Ad9-induced rat mammary tumors may lead to a detailed molecular understanding for the development of fibroadenoma, a common human breast tumor.

CDw75 antigen expression in human gastric carcinoma and adjacent mucosa

BACKGROUND

The amount of sialic acid correlates with the invasiveness and metastasizing potential of several human tumors. The CDw75 epitope is a sialylated carbohydrate determinant generated by the beta-galactosyl alpha 2,6-sialyltransferase, which can be viewed as a target for identifying biologically aggressive tumors.

METHODS

The authors performed an immunohistochemical study of CDw75 epitope expression in 87 cases of gastric carcinoma and adjacent mucosa and 331 metastases (329 lymph node metastases and 2 liver metastases) with the monoclonal antibody HH2.

RESULTS

Normal-appearing mucosa, foci of intestinal metaplasia, and foveolar hyperplasia, adjacent to the carcinomas, were mainly nonimmunoreactive. Only a few parietal cells of the body mucosa were stained with HH2. Two of 12 cases with dysplasia showed CDw75 antigen expression in dysplastic glands. Forty-one cases (47.1%) were immunoreactive for CDw75 antigen in the primary tumors or metastases. A very close relationship was found between the expression of the antigen in primary tumors and their respective metastases. The expression of the antigen was correlated with an infiltrative growth pattern, lymphatic invasiveness, and aneuploidy. All but two immunoreactive cases had lymph node metastases or lymphatic permeation. No relationship was found between CDw75 antigen expression and the morphologic types of gastric carcinoma, amount of lymphoid infiltrate, vascular invasion, and penetration of the gastric wall.

CONCLUSIONS

The authors conclude that CDw75 antigen expression can be used as a marker of malignant transformation of gastric epithelium and is a good indicator of the biologic aggressiveness of gastric carcinoma.