Immunohistochemical demonstration of estrogen receptors (ER) in formalin-fixed, paraffin-embedded human breast cancer tissue by use of a monoclonal antibody to ER

Classifying Pulmonary and Urinary High-grade Neuroendocrine Carcinoma by CK7 Immunohistochemistry

High-grade neuroendocrine carcinoma (HGNEC) is subclassified into small cell carcinoma (SmCC) and large cell neuroendocrine carcinoma (LCNEC). Although both are clinically aggressive, the SmCC and LCNEC need to have different treatment strategies, and accurate pathologic diagnosis is challenging. We studied a large retrospective cohort (186 cases) of HGNEC of bladder and lung to investigate the abundance of cytokeratin (CK) 7 expression and staining pattern in SmCC and LCNEC. Overall, the pulmonary and urinary HGNEC exhibited several different CK7 staining patterns, including negative staining (n=28), dot-like staining (n=73), partial membranous staining (n=26), and complete membranous staining (n=60). Overall, 88.9% (44/49) of pulmonary SmCC and 88.0% (44/50) of urinary SmCC showed negative or dot-like patterns for CK7, while 90.8% (59/65) of pulmonary LCNEC and 72.7% (16/22) of urinary LCNEC showed partial or complete membranous patterns for CK7 (χ 2 =105.05, P <0.0001). The distinct staining patterns were also present in those mixed SmCC and LCNEC. In addition, the specimen types or fixation did not affect CK7 staining patterns. In conclusion, CK7 has a high differential value for SmCC and LCNEC and could help guide personalized treatment for patients.

The overall survival of breast cancer patients without adjuvant therapy

PURPOSE

There are little data regarding the overall survival (OS) of patients without adjuvant systemic therapy, because most patients have been subject to standardized systemic therapies. We evaluated the baseline risk to facilitate making decisions about adjuvant therapy.

PATIENTS AND METHODS

A total of 1835 breast cancer patients who did not receive adjuvant systemic therapy between 1964 and 1992 were retrospectively evaluated. We investigated the 10-year disease-free survival (DFS) and OS according to the number of metastatic lymph nodes, pathological T classification, stage, and estrogen receptor (ER) status.

RESULTS

Survival curves showed that as the number of metastatic lymph nodes, pathological T classification, and staging increased, the 10-year OS and DFS decreased. In univariate and multivariable analyses, the number of metastatic lymph nodes was significantly associated with the DFS and OS, while in a univariate analysis, the pathological T classification and stage were significantly associated with the DFS and OS. ER positivity was a good prognostic factor for the 5-year DFS. However, between 6 and 7 years after surgery, ER negativity was a better prognostic factor than ER positivity.

CONCLUSION

We showed survival rates of patients without adjuvant therapy according to TNM classification and ER status. This information can aid in treatment selection for doctors and patients through a shared decision-making approach.

Higher ER load is not associated with better outcome in stage 1-3 breast cancer: a descriptive overview of quantitative HR analysis in operable breast cancer

PURPOSE

In breast cancer, hormone receptor (HR) status is generally a qualitative measure; positive or negative. Quantitatively measured oestrogen and progesterone receptors (ER and PR) are frequently proposed prognostic and predictive markers, some guidelines even provide different treatment options for patients with strong versus weak expression.

AIM

To evaluate quantitative HR load assessed by immunohistochemistry as a prognostic and predictive measure in stage 1-3 breast cancer.

METHODS

We reviewed all the available literature on quantitatively measured HRs using immunohistochemistry.

RESULTS

All included studies (n = 19) comprised a cohort of 30,754 patients. Only 2 out of 17 studies found a clear correlation between higher quantitative ER and better disease outcome. Only one trial examined quantitative ER both as prognostic and predictive marker and found no association between ER% and survival. Ten studies examined quantitative PR load, only two of those found a significant correlation between higher PR load and better disease outcome. Two trials examined quantitative PR both as prognostic and predictive marker, neither found any association between PR% and disease outcome.

CONCLUSIONS

There is no clear evidence for using quantitatively assessed ER and PR as prognostic nor predictive marker in patients with stage 1-3 breast cancer. We recommend only using a qualitative HR status in future guidelines and treatment considerations.

Expression of estrogen-related gene markers in breast cancer tissue predicts aromatase inhibitor responsiveness

Aromatase inhibitors (AIs) are the most effective class of drugs in the endocrine treatment of breast cancer, with an approximate 50% treatment response rate. Our objective was to determine whether intratumoral expression levels of estrogen-related genes are predictive of AI responsiveness in postmenopausal women with breast cancer. Primary breast carcinomas were obtained from 112 women who received AI therapy after failing adjuvant tamoxifen therapy and developing recurrent breast cancer. Tumor ERα and PR protein expression were analyzed by immunohistochemistry (IHC). Messenger RNA (mRNA) levels of 5 estrogen-related genes–AKR1C3, aromatase, ERα, and 2 estradiol/ERα target genes, BRCA1 and PR–were measured by real-time PCR. Tumor protein and mRNA levels were compared with breast cancer progression rates to determine predictive accuracy. Responsiveness to AI therapy–defined as the combined complete response, partial response, and stable disease rates for at least 6 months–was 51%; rates were 56% in ERα-IHC-positive and 14% in ERα-IHC-negative tumors. Levels of ERα, PR, or BRCA1 mRNA were independently predictive for responsiveness to AI. In cross-validated analyses, a combined measurement of tumor ERα and PR mRNA levels yielded a more superior specificity (36%) and identical sensitivity (96%) to the current clinical practice (ERα/PR-IHC). In patients with ERα/PR-IHC-negative tumors, analysis of mRNA expression revealed either non-significant trends or statistically significant positive predictive values for AI responsiveness. In conclusion, expression levels of estrogen-related mRNAs are predictive for AI responsiveness in postmenopausal women with breast cancer, and mRNA expression analysis may improve patient selection.

Protein tyrosine kinase signaling in the mouse oocyte cortex during sperm-egg interactions and anaphase resumption

Fertilization triggers activation of a series of pre-programmed signal transduction pathways in the oocyte that establish a block to polyspermy, induce meiotic resumption, and initiate zygotic development. Fusion between sperm and oocyte results in rapid changes in oocyte intracellular free-calcium levels, which in turn activate multiple protein kinase cascades in the ooplasm. The present study examined the possibility that sperm-oocyte interaction involves localized activation of oocyte protein tyrosine kinases, which could provide an alternative signaling mechanism to that triggered by the fertilizing sperm. Confocal immunofluorescence analysis with antibodies to phosphotyrosine and phosphorylated protein tyrosine kinases allowed detection of minute signaling events localized to the site of sperm-oocyte interaction that were not amenable to biochemical analysis. The results provide evidence for localized accumulation of phosphotyrosine at the site of sperm contact, binding, or fusion, which suggests active protein tyrosine kinase signaling prior to and during sperm incorporation. The PYK2 kinase was found to be concentrated and activated at the site of sperm-oocyte interaction, and likely participates in this response. Widespread activation of PYK2 and FAK kinases was subsequently observed within the oocyte cortex, indicating that sperm incorporation is followed by more global signaling via these kinases during meiotic resumption. The results demonstrate an alternate signaling pathway triggered in mammalian oocytes by sperm contact, binding, or fusion with the oocyte.

Enhanced expression of the PDGFR/Abl signaling pathway in aromatase inhibitor-resistant breast cancer

BACKGROUND

We have found that the platelet-derived growth factor receptor (PDGFR)/Abl signaling pathway is up-regulated as a determinant of the acquisition of resistance to estrogen deprivation in vitro. We aimed to determine its clinical relevance in aromatase inhibitor (AI)-resistant breast cancer.

PATIENTS AND METHODS

We identified a cohort of 45 patients with estrogen receptor-positive breast cancer who had been treated with an AI, subsequently relapsed and had biopsy material available from both the presentation and post-AI recurrent lesion. PDGFRα, PDGFRβ and Abl expression was assessed in formalin-fixed paraffin-embedded sections.

RESULTS

Tumor protein expression of PDGFRα (1.39-fold, P=0.0065), PDGFRβ (4.32-fold, P=0.006) and Abl (1.8-fold, P=0.001) was increased at the point of relapse. Tumor and stromal expression of PDGFRα as well as PDGFRβ was significantly correlated in pre-treatment and relapse samples. High post-treatment tumor and stromal PDGFRβ levels were associated with a short time to treatment failure (TTF). Expression of PDGFRα in relapsing tumor specimens was correlated with Abl expression and Ki67 levels. Furthermore, changes in Abl correlated significantly with changes in ER expression.

CONCLUSIONS

These clinical data support a role for enhanced PDGF/Abl signaling in AI-resistant disease and provide a rationale for targeting the pathway in endocrine-resistant breast cancer.

Relationship between estrogen receptor, progesterone receptor, HER-2 and Ki67 expression and efficacy of aromatase inhibitors in advanced breast cancer

BACKGROUND

Surprisingly few data are published on the relevance of even commonly used biomarkers of response to aromatase inhibitors (AIs) in advanced breast cancer. Here, we aim to determine the effectiveness of AIs in that setting according to quantitative levels of estrogen receptor (ER), progesterone receptor (PgR) and Ki67 or human epithelial growth factor receptor-2 (HER-2) status.

PATIENTS AND METHODS

ER, PgR, HER-2 and Ki67 protein expressions were centrally assessed in 177 archival formalin-fixed paraffin-embedded primary or locally recurrent breast tumours from women who subsequently received AI treatment of advanced disease.

RESULTS

Among ER-positive patients (n = 146), higher PgR, but not ER, levels were associated with increased time to AI treatment failure (TTF). Higher Ki67 staining was associated with decreased TTF. ER-positive/HER-2-positive patients showed a non-significant trend for decreased TTF compared with ER-positive/HER-2-negative patients. PgR level, but not Ki67, remained a significant predictor of TTF in multivariate analysis of ER-positive patients.

CONCLUSIONS

Higher PgR and Ki67 levels are significantly associated with increased and decreased TTF, respectively, in ER-positive patients receiving AI treatment of advanced disease. The higher proliferation seen in PgR-negative tumours does not explain the poorer clinical responsiveness of this subgroup.

Predictors of response to aromatase inhibitors

Aromatase inhibitors are now considered to be part of the endocrine treatment for most hormone receptor-positive breast cancer in post-menopausal women for both early and advanced disease. Despite the impressive efficacy of these agents, up to 50% of treated patients exhibit de novo or intrinsic resistance to aromatase inhibitors and hence identification of response predictors is essential to allow treatment to be directed towards responsive populations and for alternative or additional therapies to be offered to resistant patients. Emerging data seem to suggest a role for the conventional tumour markers of oestrogen receptor and progesterone receptor as possible predictors of response but, particularly in the adjuvant setting, the extent to which these are useful has not been fully elucidated. Data from both the neo-adjuvant and advanced disease settings suggest that response to aromatase inhibitors does not appear to be adversely affected by HER-2 overexpression. Within neo-adjuvant aromatase inhibitor studies, the proliferation marker Ki67 has shown a significant correlation with relapse-free survival, suggesting a role in prediction for measurement of Ki67 and other dynamic markers of response. Analysis of multiple gene expression changes over a short treatment period may also have potential clinical utility for prediction of response.

Interinstitutional variability and effect of tissue fixative on the interpretation of a Barrett cytokeratin 7/20 immunoreactivity pattern in Barrett esophagus

A unique pattern of cytokeratin (CK) 7/20 immunostaining (diffuse staining with CK7 and surface and superficial crypt staining with CK20) has been reported to be useful in differentiating Barrett esophagus (BE) from intestinal metaplasia of the stomach. However, there are conflicting results regarding the prevalence of a BE CK7/20 staining pattern in BE between different studies. Therefore, this study was performed to determine the degree of variability in interpretation of a BE CK7/20 pattern and to determine the reasons for variability when present. Esophageal and gastric mucosal biopsies from 67 patients with BE and antral intestinal metaplasia at 2 institutions were immunostained for CK7/20. All cases were evaluated for the presence of a BE CK7/20 pattern by 2 gastrointestinal pathologists from each institution, and the degree of agreement between institutions was determined. To determine the effect of tissue fixation and staining methods on the pattern of CK7/20 staining, unstained slides were exchanged between institutions, stained separately by each institution, and reexamined by all pathologists. There was excellent agreement on the presence of a BE CK7/20 staining pattern between pathologists at the same institution but only moderate agreement between pathologists at different institutions (71% overall, kappa = 0.58). Among BE cases, a BE CK7/20 staining pattern was identified in 50 (96%) of 52 cases by Cleveland Clinic Foundation pathologists but only 35 (67%) of 52 cases by Brigham and Women's Hospital pathologists. The major source of disagreement related to the interpretation of weak or variable CK7 staining of deep intestinalized mucosa in BE biopsies that were fixed in Hollande, but not those that were fixed in formalin. After the creation of a new set of criteria for a positive BE CK7/20 staining pattern, which took into account the effects of Hollande's fixative, the degree of agreement between pathologists at each of the 2 institutions was excellent (100%, kappa value = 1.0). Therefore, the CK7/20 staining pattern is influenced by the type of fixative used. Only a moderate level of interobserver agreement among pathologists regarding a BE CK7/20 pattern can be achieved if one is not aware of these effects. Nevertheless, specific criteria for interpretation of CK7/20 staining can be successfully applied between institutions and need to be developed before use of this technique in clinical practice.

Further characterization of storage-related alterations in immunoreactivity of archival tissue sections and its implications for collaborative multicenter immunohistochemical studies

Storage of unstained paraffin slides may lead to the deterioration of specimens and failure to detect cellular proteins immunohistochemically. Although the implication of age-induced alterations on multicenter immunohistochemical studies would be considerable, they have not been investigated previously. The current study was undertaken to examine the effect of this factor further and to explore new ways of overcoming the resultant shortcomings. The authors now report on the immunodetection of a host of antigens in similarly preserved unstained serial paraffin slides obtained from three centers using a panel of eight antibodies. Staining of recently prepared sections from the authors' centers resulted in similar strong patterns in seven of eight antibodies, with one antibody demonstrating variable immunoreactivity. However, storage of unstained paraffin sections at room temperature resulted in a variable but progressive decrease in expression of several tissue antigens. Although the loss in antigenicity was proportional to the length of storage, the effect was reversible if super antibody concentrations were used. The authors conclude that recently prepared paraffin sections from centers with similar fixation protocols have similar immunoreactivity and are suitable for use in comparative multicenter studies. However, in view of the delays that may attend tissue transportation during these projects, the authors suggest that test systems should be checked for age-induced antigen degradation by incubating sections with higher antibody concentrations.

Behaviour of metastasis in relation to vascular index in patients with node-positive breast cancer treated with adjuvant tamoxifen

Some experimental studies suggested that one possible oestrogen-receptor-unrelated mechanism of action of tamoxifen involves inhibition of angiogenesis. We evaluated the correlation of the degree of vascularisation of the primary tumour and we assessed it by using the panendothelial marker anti-CD31 and immunohistochemistry with microvessels count, performed at the vascular 'hot spot' of each single cancer, with the risk of recurrence in time. A cohort of 176 consecutive patients with node-positive invasive breast cancer treated with adjuvant tamoxifen (30 mg/daily for 3 years) and a median follow-up of 72 months was studied. Sixty-two patients developed metastasis (30 visceral, 18 skeletal and 14 in soft tissues) during the time of observation. The study of the hazard function for metastasis was performed by a generalized linear modelling approach with a binomial error according to Efron. The risk of first recurrence was strictly associated with vascular index, having the patients with the highest microvessel counts the highest risk of metastasis during all the period of observation. We did not find an interaction of vascularity with oestrogen receptor (ER) status. However, in the subgroup of patients with ER-positive tumours the hazard of metastasis was almost constant in time, while in that with ER-negative tumours it increased rapidly up to 20 months and, thereafter, decreased sharply. The results of our study are an indirect evidence that the patients with highly vascularized breast cancers may gain poor benefit of adjuvant tamoxifen and, therefore. that this antioestrogen is unlikely to retain a clinically relevant antiangiogenic activity in human breast cancer. Our data need confirmation by a prospective randomized clinical trial.

Immunohistochemical evaluation of estrogen and progesterone receptors in adenoid cystic carcinoma of salivary gland origin

Adenoid cystic carcinoma (ACC) is a malignant tumor of salivary gland origin, which is characterized by a high rate of local recurrence and distant metastasis even after aggressive surgical treatment. In several studies using various immunohistochemical techniques, estrogen and progesterone receptor (ER and PgR) proteins in salivary gland ACC have been identified and the possible use of endocrine therapy as a treatment modality suggested. On this basis, 27 samples of formalin-fixed paraffin-embedded salivary gland ACC were immunohistochemically evaluated for the presence of ER and PgR. ER was not detected in any of the tumors and PgR was identified in only two cases. Thus, application of hormone therapy to salivary gland ACC is not supported by the results of the present study.

Salivary gland carcinomas: prognostic significance of simple mucin-type carbohydrate antigens

The prognosis of salivary gland carcinomas is difficult to assess. Simple mucin-type carbohydrates (T and sialosyl-T antigens, Tn and sialosyl-Tn antigens) have been shown to be of value in predicting prognosis for carcinomas in other locations. We studied the prognostic significance of the expression of these structures in a retrospective study of 133 patients with salivary gland carcinomas, using immunohistochemistry and a panel of well-defined monoclonal antibodies (MAbs) on formalin-fixed paraffin-embedded tissues. Sialosyl-Tn, T and sialosyl-T antigens were not correlated with prognosis. Univariate analyses showed no overall difference in survival or locoregional control between patients with Tn-positive and patients with Tn-negative tumours, but indicated that expression of the Tn antigen was associated with early locoregional recurrences and deaths. Tn was, however, not an independent prognostic factor by multivariate regression analysis.

Lack of prognostic significance of the monoclonal antibody Ki-S1, a novel marker of proliferative activity, in node-negative breast carcinoma

In a series of 205 node-negative breast cancers (NNBC), we determined staining by the novel antibody Ki-S1, a marker of tumor cell proliferation, in order to test its association with other prognostic variables and its prognostic significance. Ki-S1 was determined in routinely formalin-fixed paraffin-embedded tumor samples. Ki-S1 gave a nuclear staining in the majority of the carcinomas (188 of 205), with percentages of reacting nuclei ranging from 2% to 90% (median value of 7%). In 107 tumors frozen sections were available to also assess the Ki-67 antibody. Among these, 94 had a nuclear staining of cancer cells ranging from 5% to 80% (median value of 7%). In 46 tumors we also determined the MIB-1 antibody. The percentage of MIB-1 nuclear staining ranged from 1% to 50% (median value of 20%). There was no significant relationship between Ki-S1 and the other two cell kinetic markers. Ki-S1 labeling was significantly associated only with tumor size (p = 0.03). With a median follow-up of 6 years, Ki-S1 had no significant prognostic value for either relapse-free survival (RFS) or overall survival (OS) (Ki-S1 as continuous logarithmic variable; p = 0.86 and p = 0.23, respectively). For RFS the following variables had a significant prognostic value: Ki-67 (< or = 10% vs > 10%; p = 0.037); progesterone receptor (PgR) expression (- vs+/++; p = 0.041); tumor size (pT1 vs pT2-3; p = 0.042) and grading (GI vs GII-III; p = 0.047). For OS, tumor size (p = 0.0044), age (continuous variable; p = 0.0060), and Ki-67 (p = 0.043) were significantly prognostic. In multivariate analysis (final model), only tumor size retained a significant and independent prognostic value for RFS (p = 0.0042). For OS, both tumor size (p = 0.0029) and age (< or = 55 years vs > 55 years; p = 0.041) retained significance in the multivariate model. In conclusion, Ki-S1 does not seem to have prognostic relevance in this series of NNBC. Possible hypotheses to explain this observation are discussed.

Estrogen and progesterone receptors in salivary gland adenoid cystic carcinoma

Adenoid cystic carcinomas of salivary glands occur more frequently in women and bear remarkable similarity to adenoid cystic carcinomas of the breast. In addition, breast carcinomas express estrogen and progesterone receptors that impact prognostic significance. This suggests a possible role for sex steroid hormones in the development and progression of salivary gland adenoid cystic carcinoma. On this basis, 12 samples of formalin-fixed, paraffin-embedded salivary gland adenoid cystic carcinomas and 12 samples of normal salivary gland tissue were immunohistochemically evaluated for estrogen and progesterone receptor protein expression. Estrogen receptors were not detected in either group; however, a significantly higher progesterone receptor level was evident in the neoplastic group compared with normal tissue (p < 0.01). These data confirm the presence of progesterone receptors within normal and neoplastic salivary gland tissue. Progesterone receptor expression may be of possible prognostic and therapeutic value in some cases of adenoid cystic carcinoma.

Estrogen and progesterone receptors in thyroid lesions

BACKGROUND

Given the higher incidence and better prognosis of thyroid cancers in women, the possibility arises that these lesions may be influenced by sex hormones. With the development of monoclonal antibodies to the estrogen and progesterone receptor proteins, receptor status can now be determined by immunohistochemical methods that allow direct localization of receptors in tissue.

METHODS

Using this technique, we have studied tissues of 11 patients, 2 of them pregnant, with thyroid lesions. Paraffin-embedded tissues were used. Positive controls consisted of known estrogen- and progesterone-positive breast carcinomas.

RESULTS

Examination of both the thyroid lesions and adjacent uninvolved thyroid tissue showed no nuclear reactivity with either estrogen or progesterone receptor antibodies. Our study did not confirm the previously reported incidence of estrogen and progesterone receptors in thyroid lesions.

CONCLUSIONS

We conclude that contrary to earlier indications, estrogen and progesterone receptor proteins are neither significantly detectable nor pertinent for follow-up or prognosis in the patient with thyroid neoplasia.

Immunohistochemical quantitation of oestrogen receptors and proliferative activity in oestrogen receptor positive breast cancer

AIM

To evaluate the effect of the duration of formalin fixation and of tumour heterogeneity on quantitative estimates of oestrogen receptor content (oestrogen receptor index) and proliferative activity (MIB-1 index) in breast cancer.

METHODS

Two monoclonal antibodies, MIB-1 and oestrogen receptor, were applied to formalin fixed, paraffin wax embedded tissue from 25 prospectively collected oestrogen receptor positive breast carcinomas, using a microwave antigen retrieval method. Tumour tissue was allocated systematically to different periods of fixation to ensure minimal intraspecimen variation. The percentages of MIB-1 positive and oestrogen receptor positive nuclei were estimated in fields of vision sampled systematically from the entire specimen and from the whole tumour area of one "representative" cross-section.

RESULTS

No correlation was found between the oestrogen receptor and MIB-1 indices and the duration of formalin fixation. The estimated MIB-1 and oestrogen receptor indices in tissue sampled systematically from the entire tumour were closely correlated with estimates obtained in a "representative" section. The intra- and interobserver correlation of the MIB-1 index was good, although a slight systematical error at the second assessment of the intraobserver study was noted.

CONCLUSION

Quantitative estimates of oestrogen receptor content and proliferative activity are not significantly influenced by the period of fixation in formalin, varying from less than four hours to more than 48 hours. The MIB-1 and the oestrogen receptor indices obtained in a "representative" section do not deviate significantly from average indices determined in tissue samples from the entire tumour. Finally, the estimation of MIB-1 index is reproducible, justifying its routine use.

Comparison of new immunohistochemical assay for oestrogen receptor in paraffin wax embedded breast carcinoma tissue with quantitative enzyme immunoassay

AIM

To validate the use of a new mouse monoclonal antibody (1D5) directed against the N-terminal domain (A/B region) of the oestrogen receptor in an immunohistochemical assay (ER-IHA) for paraffin wax embedded tissue.

METHODS

Breast cancer specimens were surgically obtained from 119 previously untreated patients. For comparison, oestrogen receptor was measured from cytosol fractions using an established oestrogen receptor enzyme immunoassay (ER-EIA) method. Oestrogen receptor "H-scores" were obtained from the ER-IHA after antigen retrieval using microwave treatment. Where discrepancies occurred between the two methods, further immunohistochemistry was performed using the H222 antibody from the Abbott Laboratories ER-ICA kit.

RESULTS

The correlation between the two methods was non- linear, but despite this there was an 86% concordance between ER-EIA and ER-IHA using the 1D5 ER antibody. Fifty four per cent of tumours (64/119) were oestrogen receptor positive and 32% (38/119) were negative by both assays. A mismatch between the ER-EIA and ER-IHA occurred in 17 cases. Seven tumours were IHA positive but EIA+, but five of these were borderline negative by EIA, having values of > 5 and < 10 fmol/mg protein. Ten tumours were IHA negative and EIA+; four of these tumours were completely negative by IHA in the section studied. A further IHA assay, carried out on the 17 tumour mismatches with H222 antibody, showed that three tumours remained substantially discordant. These three tumours were strongly positive with the 1D5 antibody and negative with the H222 antibody. Two of these discordant tumours were of the rare ER negative and PgR positive phenotype and may contain oestrogen receptor that is of biological interest but which lacks the hormone binding epitope.

CONCLUSIONS

The concordance between the classic enzyme immunoassay technique and the new immunohistochemical method on paraffin wax embedded sections was good. Moreover, the IHA technique using the 1D5 antibody against the N-terminal was easily reproducible. This technique may allow oestrogen receptor content to be determined in large cohorts of patients in whom archival tumour material is available.

Estrogen- and progesterone receptors in normal cycling endometrium as studied by end-point titration

A thorough knowledge of the normal physiological fluctuations in estrogen- (ER) and progesterone receptors (PgR) is essential to characterize the changes in ER and PgR in the abnormal endometrium. We investigated the distribution of ER and PgR in frozen human cycling endometrial tissue using the commercially available ER- and PgR-ICA kits. Two-fold end-point titration (EPT) of ER and PgR antibodies was implemented to semi-quantitate more accurately ER and PgR. Semiquantitation of ER and PgR using EPT was significantly correlated to results obtained using either simple scoring or enzyme-immunoassay (EIA) methods. ER and PgR staining fluctuated in relation to the menstrual cycle. In most subphases PgR exceeded ER in both epithelial and stromal cells. Highest levels of ER and PgR were demonstrated in the glands of the functionalis in mid-to-late proliferative phases, whereas both receptors were almost undetectable by immunohistology in the glands of mid-to-late secretory phases. Endometrial stromal cells had high and nearly constant EPT values for PgR, but low values for ER throughout the menstrual cycle. EPT values for ER and PgR were generally higher in the basalis than in the functionalis but showed similar cyclic fluctuations. Our results further substantiate the view that the response to hormonal stimulation is cell-type specific, and suggest differences in steroid metabolism according to cell type and layer.

c-erbB-3 and c-erbB-2 protein expression in node-negative breast carcinoma--an immunocytochemical study

The type I growth factor receptor family has been found to play an important role in the control of normal growth and differentiation. Moreover, the epidermal growth factor receptor and the c-erbB-2 oncogene seem to be implicated in the pathogenesis and behaviour of several cancers, including breast cancer. c-erbB-3 is a new member of the type I receptor family for which there is currently little information available on its expression in neoplastic tissues, and on its possible prognostic significance. This study was undertaken to define the prognostic value of c-erbB-3 expression in a series of node-negative breast cancer (NNBC) patients when compared, by multivariate analysis, with expression of the c-erbB-2 protein and conventional clinicopathological features. cerbB-3 was recognised by the novel monoclonal antibody RTJ1, whereas c-erbB-2 was detected by the polyclonal antibody 21N, using immunocytochemical methods. We found that overexpression of c-erbB-3 occurs frequently in NNBC. Overall, 138 of 212 carcinomas (65%) had some degree of membrane RTJ1 staining, and 28 (13%) showed strong and generalised positivity ( ). Twenty-four per cent of carcinomas had membrane 21N staining, and 12% presented strong and generalised positivity ( ). c-erbB-3 protein expression was significantly associated only with that of c-erbB-2 (P = 0.05), whereas 21N positivity was significantly associated with small tumour size (P = 0.02) and ductal histotype (P = 0.04). No significant correlation between expression of either receptor proteins or relapse-free survival was observed after a median follow-up of 63 months. Applying multivariate analysis, only tumour size approached significance. Our results indicate that analysis of expression of c-erbB-3 and c-erbB-2 alone do not seem to be useful in identifying patients with NNBC at different risk of relapse or death.

Estrogen receptor, progesterone receptor, and HER-2/neu protein in breast cancers from pregnant patients

BACKGROUND

Because the occurrence of breast cancer during pregnancy is uncommon and because the high levels of estrogens and progestins associated with pregnancy could cause false-negative results from ligand binding assays (LBA), the actual incidence of steroid hormone receptor positivity in tumors from this subset of women is unclear.

METHODS

Estrogen receptor (ER) and progesterone receptor (PgR) were determined using LBA methods in 15 tumors from 15 pregnant patients with breast cancer. In addition, immunohistochemistry was done for ER, PgR, pS2, heat shock protein 27 (hsp27), and HER-2/neu on 12 of the 15 tumors.

RESULTS

Five of 15 (33%) tumors were positive for ER by LBA, compared with 52% of tumors from age-matched nonpregnant patients. Six of 12 (50%) were ER-positive by immunohistochemistry. For PgR, 7 of 15 (47%) tumors were positive by LBA, compared with 42% of tumors from nonpregnant patients. Ten of 12 (83%) stained positive for PgR. By LBA, 67% of tumors studied were positive for ER or PgR or both, as opposed to 57% of tumors from the nonpregnant comparison group. Two other estrogen receptor-mediated proteins, pS2 and hsp27, were present by staining in 8 of 12 (67%) and 10 of 12 (83%) of tumors, respectively. Seven of 12 tumors (58%) had positive staining for HER-2/neu, whereas only 16% of age-matched nonpregnant patients had positive-staining tumors.

CONCLUSION

By LBA, the incidence of ER and PgR in breast tumors from pregnant women was not significantly different from that of tumors from nonpregnant age-matched patients. Some ER-negative tumors were PgR, pS2, or hsp27 positive, indicating that an intact estrogen response system was operative although ER was not detectable by standard LBA.

Toremifene and tamoxifen in advanced breast cancer--a double-blind cross-over trial

Toremifene (TOR) is a triphenylethylene derivative related to tamoxifen (TAM). TOR has antitumor activity, not dependent on estrogen receptors, and responses with TOR have been observed in patients with progressive disease during TAM-treatment. To elucidate possible cross-resistance between these two antiestrogens, we compared their anti-tumor activity in a randomized, double-blind, cross-over study. 66 postmenopausal women with advanced estrogen receptor positive or unknown breast cancer and a median age of 63 years (range 38-82) were included. Patients were randomized to TAM 40 mg/day or TOR 240 mg/day. Treatment continued until progressive disease, when cross-over to the alternative treatment was done. The response rate with first line TOR was 29% (95% confidence limits 10-41%) and with TAM 42% (95% confidence limits 25-61%). Response rates and response durations, survival and toxicity were not significantly different between the two treatments. 44 patients progressing on first line TAM or TOR were evaluable for second line TOR or TAM treatment. As no responses were observed, the possibility of over-looking a response rate of 20% or more is less than 1%. In conclusion, this study strongly indicates that TOR and TAM are clinically cross-resistant in patients with advanced breast cancer.

Solid and papillary neoplasm of the pancreas

In two cases of solid and papillary neoplasm of the pancreas (SPN), positive staining for argyrophil granules, chromogranin-A, neuron-specific enolase, chymotrypsin, alpha 1-antitrypsin, vimentin, cytokeratin, and estrogen receptors was present. Ultrastructurally, neurosecretory as well as zymogenlike granules were demonstrated. Measurements of mean nuclear volume and volume-corrected mitotic index discriminated between SPN and well-differentiated ductal adenocarcinoma of the pancreas, with notably lower values being seen in SPN. Silver-stained nucleolar organizer region counts showed wide overlaps. The results suggest that SPN is a tumor with mixed endocrine and exocrine features. Its low malignant potential compared to ductal adenocarcinoma is reflected in the mean nuclear volume and volume-corrected mitotic index. The presence of estrogen receptors may prove therapeutically useful.

Prediction of hormone responsiveness by mammographic parenchymal pattern in advanced primary breast cancer

Ninety-two women with advanced, unilateral breast cancer were classified according to the Wolfe and Nottingham classifications of mammographic parenchymal pattern (MPP). Both classifications of MPP were significantly correlated to the estrogen receptor (ER) status of the breast carcinoma, but could not be used for prediction of response to hormonal therapy. Age distribution was significantly different among Wolfe types as well as between ER groups, but a multiple regression analysis showed that both age and Wolfe pattern were significant and independent predictors of the ER status.

Squamous cell metaplasia of the bladder urothelium. A retrospective study of 36 patients

In a retrospective study of 28 women and eight men with squamous cell metaplasia in different parts of the bladder, including the trigone, no histopathological differences were observed among the regions. All the five (female) patients with parakeratosis had a concomitant invasive bladder tumour. Thirty-eight% of all the patients had a simultaneous neoplastic tumour. The metaplastic lesions were investigated for keratin in 13 patients, and all were positive. In seven out of eight patients, the urothelium adjacent to the squamous cell metaplasia was also positive for keratin, indicating a direct transformation of the urothelium to squamous cell epithelium. The metaplastic cells were investigated for oestrogen receptors in five men and five women, and all were negative, suggesting no relationship between estrogens and squamous cell metaplasia of the bladder. Squamous cell metaplasia in the bladder is not considered a premalignant condition. However, metaplasia and neoplastic tumours are often associated with chronic tissue damage, and the presence of metaplasia may give a warning of conditions that can also cause cancer.

Determination of estrogen receptors in paraffin-embedded tissue. Techniques and the value in breast cancer treatment

Estrogen receptor (ER) analysis in breast cancer has been used in three clinical situations: to select patients with advanced breast cancer for hormonal therapy, as a prognostic parameter, and for selection of women with early breast cancer to adjuvant hormonal treatment. ER has traditionally been measured using labelled hormone in binding assays--often in dextran-coated charcoal assays (DCC). Monoclonal antibodies to ER has permitted development of a solid phase enzyme immunoassay (ER-EIA) used for quantitative determination of ER in tissue homogenates, and have also been used for determination of ER using an immunohistochemical assay in frozen sections (ER-ICA) or in formalin-fixed, paraffin-embedded tissue (ER-PAR). A large number of studies has compared ER-EIA with ER-DCC assays. There is a good linear correlation between the two types of assay but ER-EIA measure more ER and classify a larger fraction of tumors ER-positive than conventional ER assays. Lack of clinical data makes the significance of this uncertain. Numerous studies have reported on the correlation between ER-ICA and ER-DCC or ER-EIA. There is a good correlation among the assays on classification of ER status with a median 86% concordance, but a somewhat poorer correlation between semiquantified ER of immunohistochemical assays and ER determined by the quantitative methods (median coefficient of correlation 0.67). There is a large variation in the cut-off level for definition of ER-positive in immunohistochemical assays emphasizing the need for quality control studies. The major problem involved in ER analysis in paraffin-embedded tissue is a considerable loss of immunoreactivity compared to sections from frozen tissue. This can partly be overcome by modifications of the immunohistochemical technique using enzyme pretreatment and other amplification systems, but the sensitivity of ER-PAR remains lower than ER-ICA despite these modifications, and the ER status is less reliably determined in tumors with low ER contents (< 100 fmol). The prognostic value of ER-PAR was evaluated with a multivariate analysis. The endpoint was disease-free interval in systemically untreated patients with early breast cancer, and the variables used were: ER-DCC, ER-PAR, age, tumor size, tumor grade, and nodal status. A total of 133 patients from the Danish Breast Cancer Cooperative Group's (DBCG) 77c protocols had a complete set of variables. The analysis showed that only nodal status, ER-DCC, and tumor grade were significant and independent prognostic variables. An overview of larger multivariate studies on mainly node-negative patients failed to show independent prognostic significance of ER-DCC.(ABSTRACT TRUNCATED AT 400 WORDS)

Immunocytochemical determination of the estrogen-regulated proteins Mr 24,000, Mr 52,000 and DF3 breast cancer associated antigen: clinical value in advanced breast cancer and correlation with estrogen receptor

The Mr 24,000 and Mr 52,000 estrogen-regulated cytosol proteins, and the breast cancer-associated antigen DF3 have been studied in an immunocytochemical assay. Primary tumor specimens from 119 patients with advanced breast cancer who received endocrine therapy have been studied. Monoclonal antibodies were used for the detection of the proteins in formalin-fixed paraffin-embedded blocks. No correlation between Mr 52,000-positive specimens and the presence of estrogen receptor (ER) could be established (p = 0.87, chi-square test) whereas a statistically significant association between Mr 24,000 (p = 0.0002), DF3 antigen (p = 0.044) and ER was demonstrated. No intercorrelation was found between Mr 24,000 and Mr 52,000 or DF3 (p = 0.63, 0.98 and 0.12 respectively). Clinical response was evaluated for immunocytochemical findings, Mr 24,000 (p = 0.37), Mr 52,000 (p = 0.61) and DF3 (p = 0.68) showed no association whereas ER was statistically correlated (p = 0.00005). Neither overall survival nor disease-free survival correlated to Mr 24,000 (p = 0.18 and 0.75 respectively, logrank test), Mr 52,000 (p = 0.095 and 0.38), or DF3 (p = 0.22 and 0.13) staining, whereas ER-positive tumors did (p = 0.00005). Discrimination between ER-positive responders and ER-positive non-responders was not possible using either Mr 52,000, Mr 24,000 or DF3 staining. Based on our findings we conclude that immunocytochemical staining for Mr 52,000, Mr 24,000 or DF3 cannot be used as a marker to predict response to endocrine therapy in patients with advanced or recurrent breast cancer.

Enzyme immunoassay of oestrogen receptors in needle biopsies from human liver

For quantitative assessments of sex hormone receptors in liver tissue, ligand binding assays are inconvenient, as they require large biopsies (0.5-1.0 g). The present study shows that it is possible to measure oestrogen receptors (ER) quantitatively in needle biopsy specimens as small as 10 mg by modifications of a commercial enzyme immunoassay employing monoclonal antibodies. Sucrose gradient centrifugation and the dextran charcoal method served as reference methods. A consecutive series of needle biopsies from patients suspected of liver disease were investigated. The biopsies (n = 37) had a median weight of 14 mg and cytosolic protein concentrations greater than 1 mg/ml (median 1.28 mg/ml). The median ER concentration was 20 fmol/mg cytosolic protein (range 5 to 57 fmol/mg). The intra-assay coefficient of variation was 8.9%, the inter-assay 13.2%, and the detection limit 2.7 fmol/ml cytosol. Women had significantly higher ER concentrations (median 22 fmol/mg) compared to male patients (median 16 fmol/mg) (P = 0.007). The enzyme immunoassay measures ER in liver specimens as small as 10 mg, compared to the large tissue specimens necessary for the conventional DCC assay, and the method is a convenient tool for further studies of ER in routine needle biopsies from the liver.

Detection of estrogen receptor (ER) in the rat brain using rat anti-ER monoclonal IgG with the unlabeled antibody method

Application of Sternberger's unlabeled antibody enzyme method for detection of the estrogen receptor (ER) using a rat primary antibody with rat tissues has been discouraged, presumably because nonspecific staining of endogenous IgG was expected with the required anti-rat IgG bridging antibody. Because the blood-brain barrier greatly reduces immunoglobulin infiltration into the brain, we hypothesized that rat brain tissue could be specifically immunostained using rat IgG primary antibodies. A rat monoclonal anti-ER antibody (H222) specifically stained ERs in the brains of ovariectomized but not in ovariectomized estrogen-treated rats. In contrast, the uterus, a well-perfused target organ stained intensely in a nonspecific fashion. Dense populations of estrogen receptors were observed in the medial preoptic area, the bed nucleus of the stria terminalis, and the arcuate and ventromedial nuclei of the hypothalamus. A monoclonal rat IgG directed against alpha-tubulin labeled primarily cortical dendrites quite distinct from the neuronal nuclei that are the primary antigenic sites for the estrogen receptor antibody. These results confirm that the sensitive unlabeled antibody method can be applied to rat brain tissues, even when the primary antibody is rat IgG and that labeling of endogenous IgG may be used as a simple method to evaluate the integrity of the blood brain barrier.

Demonstration of oestrogen receptor in symptomatic breast carcinoma, using fine needle aspiration cytology

Oestrogen receptor immunocytochemical assay (ER-ICA) was used to determine oestrogen receptor (ER) content of cells in fine needle aspirate (FNA) specimens from 88 breast carcinomas. In 49 of these the radioligand binding assay for oestradiol was available for comparison. The predictive value of ER-ICA staining for a positive radioligand binding assay (greater than 10 fmol/mg protein) was 95%. Although the predictive value of negative staining was only 66%, 34 out of 37 ER-ICA negative tumours had radioligand binding assays below 60 fmol/mg protein. ER-ICA staining showed a strong positive correlation with age of the patient, positivity being rare before the menopause. There was a weak inverse correlation with tumour grade but none with tumour size or lymph node status. The assessment of ER by immunocytochemistry using FNA cytology is a rapid technique, which may easily be repeated and provides a pre-operative assessment of ER status. It allows confirmation that tumour cells are present in the sample and an assessment of tumour heterogeneity.

Hormonal dependency of cerebral meningiomas. Part 1: Female sex steroid receptors and their significance as specific markers for adjuvant medical therapy

Female sex steroid receptors were examined in 50 human cerebral meningiomas. For estrogen receptors, high-affinity binding sites (dissociation constant (Kd): 0.05 to 0.2 nM) were found in the cytosolic fraction with a capacity of less than 4 fmol/mg protein in 10 meningiomas using a dextran-coated charcoal (DCC) assay. In the same cytosolic fraction, the solid-phase enzyme immunoassay revealed only one cytosol with a positive colorimetric reaction equal to 5 fmol/mg protein. However, in the nuclear compartment, none of the tumors stained positively for estrogen receptors with immunohistochemical techniques. In addition, the most convincing evidence for the absence of estrogen receptors was obtained by in situ hybridization using an oligonucleotide probe complementary to a fraction of the human receptor messenger ribonucleic acid (mRNA). In none of the 50 meningiomas was the expression of estrogen mRNA coding for the estrogen receptor detected. For progesterone receptors, high-affinity binding sites (Kd: 0.3 to 2.6 nM) were found in 49 of the 50 tumors using a DCC assay. In the same cytosols, solid-phase enzyme immunoassay revealed that each tumor was positive for progesterone receptors. However, in the nuclear compartment, only five tumors had partially positive staining for progesterone receptors with immunohistochemical techniques. Within the confines of this study, it is concluded that: 1) the estrogen receptor is generally absent in meningioma tissue, and 2) the progesterone receptor is mainly absent in the nuclear compartment, leading to the conclusion that the cytosolic progesterone receptor may be an inactive form. This study suggests that female sex steroid receptors are not primarily involved in the proliferative rate of cerebral meningiomas and that they are of no current significance as markers for adjuvant medical therapy of most meningiomas.

The prognostic value of immunohistochemical estrogen receptor analysis in paraffin-embedded and frozen sections versus that of steroid-binding assays

Estrogen receptors (ER) were independently analyzed using dextran-coated charcoal assays (ER-DCC) and immunohistochemical assays in frozen (ER-ICA) and paraffin-embedded tissue (ER-PAR) from 130 human breast cancer specimens drawn from postmenopausal high-risk patients registered in the Danish Breast Cancer Cooperative Group. ER was best detected with the ER-DCC assay followed by the ER-ICA (relative sensitivity 87%) and the ER-PAR assays (relative sensitivity 71%). The semiquantified staining features of the immunohistochemical assays were statistically significantly correlated with each other and with ER-DCC. Analysis of disease-free interval (DFI) and overall survival (OS) showed that all assays allowed statistically significant discrimination between a high risk and a low risk group, although the sensitivity differences tended to be reflected as small differences in clinical discriminatory power. The patient groups were then stratified according to adjuvant treatment [radiotherapy (RT) versus radiotherapy and tamoxifen (RT + TAM)]. The survival advantage was tied primarily to the receptor status itself in the steroid-binding assays, but was linked to both the receptor status and the adjuvant treatment in the immunohistochemical assays. Thus, the relative risks in terms of DFI and OS were of the same relative magnitude in the RT and RT + TAM groups for ER-DCC assays using a cut-off level of 10 fmol/mg cytosol protein, while there were large differences in the relative risks between RT and RT + TAM groups for ER-ICA and ER-PAR assays. We conclude that an ER assay in fresh tissue should be given first priority, but if there is no fresh tissue, an ER assay in paraffin-embedded tissue offers a reasonably good alternative as a prognosticator and an equivalent alternative as a predictor of the response to endocrine treatment.

Immunohistological study of oestrogen receptors in breast carcinomas that are biochemically receptor negative

The reliability of an immunohistological method, applied to paraffin wax sections, was assessed for determination of oestrogen receptor content of biochemically oestrogen receptor negative breast carcinomata. Sixty consecutive tumours with oestrogen receptor concentrations of less than 10 fmol/mg cytosol protein, as estimated by dextran-coated charcoal biochemical assay, were examined. Paraffin wax sections were treated with DNAse before applying a peroxidase-anti-peroxidase method using ER-ICA monoclonal antibodies. Fifty one cases (85%) were negative, six (10%) weakly positive, and three (5%) were moderately positive. No strongly positive cases were seen. It is suggested that cases with weakly positive staining, especially when localised to a small area, should be regarded as negative. On the other hand, as the three moderately stained cases included two small tubular carcinomas and an invasive ductal carcinoma with high progesterone receptor concentrations, it is more likely that the biochemical assay in these cases represented false negative results due to sampling error or inclusion of fibrous or other non-neoplastic tissue in the assayed samples. It is concluded that the immunohistological method used here is fairly reliable and would be especially valuable for determination of oestrogen receptor content in small, mammographically detected tumours from which no tissue would be available for biochemical assay or frozen section examination.

Oestrogen receptor (ER) analysis in B-cell chronic lymphocytic leukemia: correlation of biochemical and immunocytochemical methods

Oestrogen receptors (ER) are present in neoplastic lymphoid cells and have been considered a physiological marker of growth rate or differentiation. Tamoxifen, an oestrogen antagonist, has been given in some patients with CLL and Hodgkin's disease, with dramatic response in single cases. Until now, ER status has been assessed using a steroid binding assay (SBA) which has many inherent problems. Recently, the development of monoclonal antibodies directed against ER has been applied to the study of breast carcinomas and results obtained show good correlation with the quantitative SBA. We studied 49 cases of B-cell chronic lymphocytic leukemia (CLL) using immunostaining of cytospin preparations. In 30 of these cases ER enzyme immunoassay (ER-EIA) was also performed. Cultured MCF-7 cells, derived from a pleural effusion of a breast cancer patient, known to contain high levels of ER were used as a positive control (40-48% ER positive cells by immunocytochemistry; 200 fmol/mg protein by EIA). All of the CLL cases except two (96%) were negative for ER (less than 1% staining; less than 4 fmol/mg protein). The two positive cases expressed granular ER staining over the nucleus (9.2 and 12.1% positive cells) and were positive by EIA and SBA. It is concluded that (i) patients with CLL rarely express ER and (ii) immunocytochemical staining of cytospin preparations is a valid technique for the measurement of ER. It is of interest that one of the positive cases was diagnosed as CLL with Richter's transformation confirming earlier findings.

Immunohistochemical estrogen receptor determination in paraffin-embedded tissue. Prediction of response to hormonal treatment in advanced breast cancer

A new immunohistochemical assay using a monoclonal estrogen receptor (ER) antibody (H222, Abbott Laboratories, North Chicago) for determination of ER in formalin-fixed paraffin-embedded tissue was applied to evaluate its clinical value in a group of 145 previously untreated patients with advanced breast cancer. Suitable histologic material was accessible in 137 of these patients, of whom 70% had ER-positive tumors. The ER-positive patients had a significantly longer median overall survival than ER-negative patients (67 versus 32 months, P much less than 0.001) and this was an effect of both a prolonged disease-free interval (27 versus 17 months, P less than 0.05) and a prolonged survival after recurrence (41 versus 15 months, P much less than 0.001). Response to endocrine therapy was obtained in 49% of the patients with ER-positive tumors and in 7% with ER-negative tumors (P much less than 0.001). Relationship between response and semiquantified individual staining features could not be established. It is concluded that ER analysis in formalin-fixed paraffin-embedded tissue offers clinically useful information for allocation of patients to endocrine therapy.

Immunocytochemical determination of the estrogen-regulated protein Mr 24,000 in primary breast cancer and response to endocrine therapy

Monoclonal antibodies against an estrogen-regulated Mr 24,000 cytosol protein (p24) were used for immunocytochemical localization of p24 in formalin-fixed paraffin-embedded specimens from the primary tumor in 103 patients who received endocrine therapy for advanced breast cancer. Sixty-one per cent of the tumors showed p24-positive staining, and this correlated well with the presence of estrogen receptor (ER) (P = 0.00017, chi-square test). Response to endocrine therapy was obtained in 43% of the patients. A statistically significant association between p24 status and response could not be established, while response and ER status were highly correlated (P = 0.0000029, chi-square = 21.6). Discrimination between ER-positive responders and ER-positive non-responders was not possible using p24 staining.