Estrogen receptor heterogeneity and the relationship between estrogen receptor and the tritiated thymidine labeling index in human breast cancer

Laryngeal cytological aspects in women with surgically induced menopause who were treated with transdermal estrogen replacement therapy

OBJECTIVE

To investigate the effects of estrogen replacement therapy (ERT) on laryngeal cytology in postmenopausal women.

DESIGN

Prospective open clinical trial.

SETTING

Outpatient menopausal clinic in the Department of Gynecology, University of Catania, Catania, Italy.

PATIENT(S)

Eighty-four healthy, surgically postmenopausal women, of whom 48 were treated with ERT and 36 were considered as a control group.

INTERVENTION(S)

Transdermal E(2) treatment by patches or gel, evaluation of laryngeal cytology with cytobrush by indirect laryngoscopy, and questionnaire for the voice history.

MAIN OUTCOME MEASURE(S)

Changes in cytologic aspects of laryngeal cells with respect to vaginal cytology by hematoxylin and eosin staining; subjective voice changes.

RESULT(S)

Sixty-seven women completed the study. Ten women from the ERT group and five from the control group dropped out because of the invasive laryngoscope method; two subjects in the control group were excluded because of pathologies of the vocal cord. Hematoxylin and eosin staining confirmed similar superficial-intermediate aspects of the cells between the laryngeal and the vaginal smears in ERT-treated women. In the control group, both smears showed aspects of atrophy-dystrophy. The ERT group had a subjectively better quality of voice than the control group.

CONCLUSION(S)

Our study confirms that the larynx is an estrogen target, as are vaginal cells. ERT may provide prevention and treatment of dystrophic pathologies of the vocal cords in postmenopausal women.

Oestrogen receptor: a stable phenotype in breast cancer

Oestrogen receptor (ER) expression in breast cancer is regarded as a phenotype that may change during the natural history of the disease or during endocrine therapy. It has been suggested that in up to 70% of tumours that show acquired resistance the mechanism may be changed in ER status from positive to negative. This paper proposes an alternative hypothesis that ER expression in a stable phenotype in breast cancer. The paper reviews the literature on ER expression during the natural history of breast cancer in patients and also presents data on the effect of endocrine therapy on ER expression. If the alternative hypothesis is true it has important implications for treatment from chemoprevention to acquired endocrine resistance in advanced disease. Equally, if the hypothesis is true, attempts to develop laboratory models of endocrine resistance where ER-positive tumours become ER negative need to be re-evaluated.

Immunohistochemical study of estrogen receptors in primary breast carcinomas and their lymph node metastases including comparison of two monoclonal antibodies

Estrogen receptors (ER) status was investigated in 101 primary breast carcinomas and their axillary lymph node metastases to determine if the malignant cells retained or changed this phenotypic feature during the metastatic process. Immunohistochemistry with the ER-ICA kit (Abbott Laboratory) on formalin-fixed paraffin-embedded tissue was used (paraffin ER-ICA). The ER status in primary and secondary tumours was concordant in 80 patients (79%) and discordant in 21 (21%). Eighteen of these twenty-one patients had ER-positive primary tumours and ER-negative lymph node metastases. This discordance, which may be due to loss of ERs in the metastatic cells or tumour heterogeneity, could explain the well-known failure of endocrine treatment in some of the patients with ER-positive primary tumours. A new monoclonal antibody ID5 (DAKO) against ERs was applied on formalin-fixed paraffin-embedded tissue from 83 of these 101 primary carcinomas. These analyses and paraffin ER-ICA analyses were compared to prior analyses of the same 83 tumours using the ER-ICA kit on fresh frozen tissue ("gold standard", frozen ER-ICA). Kappa coefficient, sensitivity and specificity were 0.74, 0.96 and 0.75 for ID5 antibody, and 0.59, 0.72 and 0.96 for ER-ICA antibody on paraffin sections.

The prognosis of breast cancer patients in relation to the oestrogen receptor status of both primary disease and involved nodes

Nodal involvement is accepted as the best single marker of prognosis in breast cancer. However, there is little information on the sub-division of node-positive patients according to the oestrogen receptor status of the nodal tissue. We have previously reported (Eur. J. Ca. 1987, 23, 31) that, in almost all cases, involved nodes are only oestrogen receptor positive (ER+) in patients whose primary tumours are uniformly ER+. This paper presents clinical follow-up on a larger group of patients with node positive breast cancer. For each patient, both soluble and nuclear receptor concentrations were determined in three separate parts of the primary tumour and in at least one involved node (we have previously defined tumours which contained ER in all six fractions of the primary as HS++, those lacking receptor in some fractions as HS+- and wholly receptor negative tumours as HS--). Median follow-up time was 71.5 months. As expected, patients whose tumours were HS++ had a significant (P less than 0.008) survival advantage. More importantly, patients with ER in both the soluble and nuclear fractions of their involved nodes survived significantly (P less than 0.003) longer than those with ER- nodes. Thus, full oestrogen receptor status of involved nodes will give sufficient prognostic information when adequate primary tissue is not available.

A meta-analysis of reported correlations between prognostic factors in breast cancer: does axillary lymph node metastasis represent biology or chronology?

A statistical overview of published results on correlations between various prognostic factors in breast cancer was undertaken. A distinction was made between clinical (or anatomical) prognostic factors--namely, axillary lymph node status and tumour size--and eight different biological prognostic factors. The latter included: tumour grade, oestrogen and progesterone receptor status, thymidine labelling index, DNA ploidy, S-phase fraction, epidermal growth factor receptor expression and c-erbB-2 gene amplification (or overexpression). 139 articles were eligible for review which reported a total of 432 individual correlations. A simple form of meta-analysis was employed: the counting method, in which the number of studies achieving a statistically significant correlation or not were counted. For each possible correlation examined, the proportion of studies showing a statistically significant correlation was calculated and an exact binomial 99% confidence interval determined for that proportion. If the 99% confidence interval included 5% (the proportion of correlations that would be expected to be statistically significant if the null hypothesis was true), it was taken as failing to exclude the null hypothesis of a zero correlation, while if it excluded 5% it was taken as rejecting the null hypothesis of a zero correlation. A broad agreement was found among published reports on the existence of a statistically significant correlation between the various biological prognostic factors in breast cancer. Of the 20 correlations examined, 18 had a 99% confidence interval excluding 5%, thus rejecting the null hypothesis of a zero correlation. On the other hand, a completely different result was obtained when reports on possible correlations between lymph node status and tumour size on the one hand and the eight biological prognostic factors on the other were analysed. Of the 16 correlations examined, 13 had a 99% confidence interval including 5%, failing to reject the null hypothesis of a zero correlation. These observations suggest the hypothesis that the prognostic influence of node status and tumour size cannot be explained by an analysis of the biology of breast cancer; and is compatible with the contention that axillary node status is merely a reflection of the relative chronological age of breast cancer.

Enzyme immunoassay of estrogen and progesterone receptors in drill biopsy specimens from breast cancer

We have applied enzyme immunoassay (EIA) to the detection of estrogen and progesterone receptors (ER and PR, respectively) in small samples obtained by drill biopsy of primary breast cancers. Thirty patients with breast cancer underwent drill biopsy of the tumors just before mastectomy. Both the drill biopsy and surgical specimens were assayed for ER and PR in the cytosol and nuclear fractions by EIA. ER and PR in the cytosol fraction (ERc and PRc, respectively) of the drill biopsy specimens (DBS) correlated very well with those of the surgical specimens (SS): ERc (DBS) = 1.02 X ERc (SS) + 3.85 fmol/mg protein (r = 0.958) and PRc (DBS) = 1.05 X PRc (SS) + 3.87 fmol/mg protein (r = 0.958). ER and PR in the nuclear fraction (ERn and PRn, respectively) of the drill biopsy specimens also correlated very well with those of the surgical specimens: ERn (DBS) = 1.02 X ERn (SS) + 59.18 fmol/mg DNA (r = 0.932) and PRn (DBS) = 0.98 X PRn (SS) + 54.28 fmol/mg DNA (r = 0.898). These results demonstrate that EIA for ER and PR of the drill biopsy specimens is a very useful method for the estimation of the receptor status of breast cancers.

Cell proliferation kinetics in human solid tumors: relation to probability of metastatic dissemination and long-term survival

A large number of studies have investigated the relationship between the long-term survival and the percentage of tumor cells in S phase assessed by autoradiography after tritiated thymidine labelling, image cytometry, flow cytometry or labelling with an halogenated analog of thymidine, in various types of human solid tumors. The survey of the results clearly shows that the S-phase fraction (SPF) is of high prognostic significance in several types of cancers, in particular in breast cancers, non-Hodgkin lymphomas, ovarian cancers, neuroblastoma, bladder cancers and lung cancers. SPF was found of high independent significance in 10 of the 11 studies in which multivariate analyses of prognostic factors had been carried out. Proliferation appears generally to be of higher prognostic significance than ploidy. In view of the wide differences in the biological characteristics of the tumors studied, it is likely that the association between a high proliferation rate and the degree of tumor aggressiveness is a general feature of human solid tumors. However, high proliferative rate of tumor cells is probably not the cause of tumor biological aggressiveness but a variable associated with it. The extent to which cells escape from the regulatory systems which control their proliferation appears to be a good index of tumor progression.

Do multiple oestrogen receptor assays give significant additional information for the management of breast cancer?

In 101 breast cancer patients, measurement of oestrogen receptor status in multiple biopsies across a tumour reveals a highly significant difference in the proportion of patients remaining either disease-free (P less than 0.04) or alive (P less than 0.005), when those with uniformly receptor positive (++) primary tumours are matched with clinically comparable patients whose tumours were homogeneously receptor negative (--). Mean follow-up time was 85 months. The prognostic value of this discriminant is particularly striking in the 53 patients with involved nodes at presentation. Of these, 13 were (++) and seven remain alive of whom six are disease-free, whereas 24 of the 29 (--) patients are dead. These results further suggest that receptor assay on a single homogenate gives less clinical information than do assays on multiple biopsies across the tumour. For patients with involved nodes, clinical management may best be decided after determination of 'macroheterogeneity'.

Factors affecting relapse in node-negative breast cancer. A multivariate analysis including the labeling index

Between 1975 and 1982, 167 patients with carcinoma of the breast without axillary lymph node metastases were studied. The thymidine labeling index (LI), representing the percentage of cells in the DNA synthesis phase, was measured in all these patients. High LI values were more frequently encountered in young patients (P = 0.05), in low estrogen receptor (ER) tumor content (P = 0.007) and in high grade tumors (P = 0.0002). The overall 8-year relapse-free survival (RFS) was 68%. Univariate analysis demonstrated that RFS was influenced by histological grading (P = 0.03), ER (P = 0.03), PR (P = 0.02) and LI (P = 0.01). Multivariate analysis using the Cox regression model selected the LI as the single significant prognostic factor with regard to RFS (P = 0.037). These results emphasize the important role of cell proliferation kinetics in defining node-negative breast cancer patients with a high risk of relapse.

Reproductive events, occurring in adolescence at the time of development of reproductive organs and at the time of tumour initiation, have a bearing on growth characteristics and reproductive hormone regulation in normal and tumour tissue investigated decades later--a hypothesis

Both animal and human data indicate that reproductive events taking place early in reproductive life may have an important influence on growth characteristics and reproductive hormone regulation in both normal tissue and neoplastic tissue investigated later in life.

Nucleolar grading of breast cancer. Comparative studies on frequency and localization of nucleoli and histology, stage, hormonal receptor status and lectin histochemistry

The localization and number of nucleoli of tumour nuclei were examined after conventional histological typing of breast carcinomas (WHO classification), staging, biochemical receptor status, and lectin binding site histochemistry. With increasing histological atypia and grade of malignancy, the frequency of nucleoli increased significantly and their location shifted from the center to the nuclear periphery. These changes correlated with an increase in indices of mitosis and cell loss. The nucleolar size correlated with the increase in the grade of malignancy. Hormone receptor and lectin binding site positive carcinomas were characterized by a low nucleolar frequency and by small nucleoli in central position, whereas carcinomas with high grades of malignancy and negative hormone receptor and lectin binding site status showed large, often multiple nucleoli in eccentrical position at a high frequency. The studies have demonstrated that nucleolar status is an easily practicable histological/cytological method for use in the assessment of prognosis of carcinomas of the breast.

Histological grade and steroid receptor content of primary breast cancer--impact on prognosis and possible modes of action

The clinical course of breast cancer was related to degree of anaplasia (DA) and steroid receptor (SR) content of primary tumours in 743 patients (pts) with clinical recurrence, initially enrolled in the DBCG-77 protocols. The oestrogen receptor (ER) and the progesterone receptor (PgR) content was known in 110 and 67 pts. The recurrence-free interval, survival after recurrence, and the overall survival were all prolonged in patients with well differentiated tumours or with high SR content. The tumour growth rates were estimated as clinical rates of progression (i.e., the time elapsed from a single distant metastasis until dissemination). The progression rate was prolonged in relatively well differentiated as well as in receptor rich tumours. The extent of dissemination, as indicated by the number of metastatic sites, was not associated with either DA or SR content. However, the anatomical distribution of metastases varied with both DA and SR content: signs of poor prognosis (high DA or low SR content) were associated with occurrence of visceral metastases. In contrast, SR rich tumours had a propensity for recurrence in bone. The results suggest that the impact on prognosis of the features examined here includes both variations in growth rate and metastatic pattern.

Correlation of DNA flow cytometric results and other prognostic factors in primary breast cancer

The percentage of cells in S-phase and DNA-ploidy have been measured in 300 primary mammary carcinomas by means of DNA-flow cytometry (FCM). The data were compared with the age and menopausal status of the patients as well as with the size, regional lymph-node involvement, histologic type, grade and concentration of estrogen (ER) and progesterone (PR) receptors of the tumors. A DNA-diploid distribution of the G0/1-peak was found in 37.6% of the cases. The mean percentage of S-phase fractions was 4.83. DNA-aneuploid tumors had significantly higher amounts of S-phase fractions (6.12%) than DNA-diploid tumors (2.66%). There was also a significant correlation between the DNA measurement data (DNA-ploidy and S-phase fractions) and histologic grade, as well as the content of ER and PR, but not between DNA-ploidy, S-phase fractions, tumor size (T) and evidence of axillary lymph-node metastases. DNA-FCM gives a biological characterization of the tumor in addition to the histopathologic examination. The method can be used as a routine procedure because of the reliability and reproducibility of the results as well as the short time needed for the measurements.

Progress in understanding breast cancer: epidemiological and biological interactions

Little progress has been made recently in our understanding of the epidemiology of breast cancer. While results from epidemiologic studies regarding reproductive factors remain fairly reproducible from one study to another, other associations such as that between breast cancer risk and dietary fat intake, although biologically plausible, are not consistently found in direct study of humans, while yet other associations, which appear less plausible biologically, become stronger (such as the increased risk associated with modest levels of alcohol consumption). In this paper we attempt to review the epidemiology and biology of breast cancer jointly and describe possible mechanisms of breast cancer induction, the cellular composition of the breast, the epidemiology of breast cancer, and salient biological features, and attempt to reconcile the biology and epidemiology. It becomes obvious that future progress depends on better biological thinking by epidemiologists, and vice-versa. Areas of further research are suggested and discussed, concluding that the ability to measure diet with greater precision could have an important role to play in clarifying our understanding of breast cancer.

Relevance of cell kinetics to hormonal response of receptor-positive advanced breast cancer

The relationship between cell kinetics and hormonal status and the relevance of the cell kinetic variable on success of hormone-therapy in estrogen receptor positive (ER+) breast tumors were analyzed in patients with advanced disease. Cell kinetics were evaluated as in vitro 3H-thymidine labeling index (LI), and estrogen receptor (ER) and progesterone receptor (PgR) with the dextran-coated charcoal technique. The analyses performed on primary tumor or soft tissue metastases from 52 patients showed a general association between the presence of hormone receptors and low proliferative activity, or the absence of receptors and high proliferative activity (ER and L.I.: p greater than 0.05; PgR and L.I.: p = 0.05). However, hormonal status and cell kinetic status were unrelated in about 40% of the cases. Clinical response to additive hormonotherapy was analyzed in relation to pretreatment LI in 29 patients with ER+ tumors. Time to reach maximum response was significantly longer in slow than in fast proliferating tumors, but complete remission was reached in 88% of slow proliferating tumors compared to only 46% of fast proliferating tumors. These preliminary results show that ER+ fast proliferating tumors largely escape hormonal control, and if confirmed on larger series, could identify cell kinetics as an important tool to select patients who will benefit from hormonal treatment.

The potential value of imprint cytology in cytochemical localization of steroid hormone receptors in ovarian cancer

Steroid hormone receptors were studied in 45 patients with primary, recurrent, or metastatic ovarian cancer in cryostat-frozen sections and imprint preparations. The ligands, 17 B-estradiol-6-carboxymethyloxine-bovine serum albumin fluorescein isothiocyanate (FITC-BSA estradiol) and hydroxyprogesteronehemisuccinate bovine serum albumin tetramethylrhodamine isothiocyanate (TMRITC-BSA progesterone) were used in the fluorescent cytochemical method. Results were compared with standard dextran-coated charcoal (DCC) biochemical assay. An overall significant correlation between biochemical values and cytochemical results was found. However, the imprint results were more sensitive and more specific than the frozen section results. A statistically significant difference (P less than 0.05) was observed between touch preparation material and frozen section specimens by the fluorescent method.

Proliferative index in breast carcinoma determined in situ by Ki67 immunostaining and its relationship to clinical and pathological variables

Sixty cases of primary breast carcinoma have been studied using a monoclonal antibody, Ki67, which recognizes an antigen expressed by cells in G1, S, G2, and M phases of the cell cycle but not Go. A Ki67 score (positive cells/total tumour cells) was determined, and possible relationships between this index of cellular proliferation and a number of clinical and pathological parameters were investigated. There was a strong positive correlation between the Ki67 score and mitotic index (p less than 0.001), a weak negative correlation with age (p less than 0.02), and weak positive correlations with histological tumour grade (p less than 0.03), tumour necrosis (p less than 0.01), and cellular reaction (p less than 0.01). No relationship was noted between the Ki67 score and tumour size, nodal status, tumour oestrogen receptor levels, or menopausal status. The Ki67 score may prove to be an objective indicator of biological behaviour and thus be of clinical significance, particularly since it is not strongly related to other clinical and pathological parameters used in predicting outcome in breast carcinoma.

Cell kinetics of histologic variants of in situ breast carcinoma

A thymidine labeling study of cell kinetics of 61 in situ breast carcinomas showed relationships between histological characteristics and kinetics. The thymidine labeling index (TLI) was significantly lower in cribriform-papillary intraductal carcinoma (median 1.30%, geometric mean 1.18%, mean 1.83 +/- 0.45%) and lobular carcinoma in situ (median 1.43%, geometric mean 1.12%, mean 1.63 +/- 0.46%) than in comedo intraductal carcinoma (median 4.40%, geometric mean 3.74%, mean 5.15 +/- 0.86%). The results for solid intraductal carcinoma, which is a less well defined and more heterogeneous entity, were intermediate (median 2.45%, geometric mean 2.40%, mean 3.32 +/- 0.80%). When invasive carcinoma was also available for kinetic study, the TLI of in situ and invasive components were usually similar (r = 0.66). The data indicate that the TLI usually does not change during the transition from in situ to invasive carcinoma. Cribriform-papillary intraductal carcinoma is a slowly proliferating entity that gives rise to slowly proliferating invasive carcinomas with relatively high levels of estrogen and progesterone receptors. Lobular carcinoma in situ similarly has low proliferative rates and gives rise to slowly proliferating invasive carcinomas. Intraductal comedocarcinoma has relatively high proliferative rates and gives rise to invasive carcinomas with high proliferative rates that often are receptor-negative. Nine of the 11 in situ carcinomas that were associated with invasive tumor and subsequent local recurrence or metastasis had TLIs above the median, and seven were comedo type with high TLIs. Our observations from thymidine labeling are consistent with a viewpoint regarding cribriform-papillary intraductal carcinoma as relatively bland, and comedo intraductal carcinoma as a distinctly more dangerous entity. Solid intraductal carcinoma seems to resemble cribriform-papillary more closely than comedo intraductal carcinoma.

Determination of DNA synthesis, estrogen receptors, and carcinoembryonic antigen in isolated cellular subpopulations of human breast cancer

Primary breast adenocarcinomas obtained from ten patients were enzymatically digested using collagenase (1 mg/ml), hyaluronidase (1 mg/ml), elastase (0.1 mg/ml) and DNAse (0.2 mg/ml). The tumor cells were labeled with 3H-thymidine and, in some cases, with 3H-estradiol. The isolated cells were submitted successively to a Ficoll-Hypaque and a bovine serum albumin gradient, from which 12 fractions were obtained. In each fraction, several characteristics were determined: carcinoembryonic antigen (CEA), thymidine (dThd) incorporation, and estrogen receptors (ER). Three main cellular subpopulations were characterized: An intermediate density subpopulation (1.046-1.054 g/ml), in which the proliferating cells are concentrated. In this subpopulation a small number of CEA-positive cells are present, but ER containing cells are virtually absent. A high-density, small cell subpopulation that concentrates most of the ER-containing cells. This subpopulation lacks proliferating cells, but CEA-containing cells are abundant. A low-density subpopulation, lacking proliferating cells and with scarce ER-positive cells, although CEA-positive cells are frequent. These findings strongly suggest that proliferating cells lack ER.

Morphology of MXT mouse mammary tumors. Correlation with growth characteristics and hormone sensitivity

The transplantable MXT mouse mammary tumor has been a useful tool for studying endocrine mechanisms underlying mammary tumor growth. It is our experience, however, that this model is unstable during serial transplantation. This paper analyses this variability from the viewpoints of histology and estrogen receptor content and indicates that these parameters should always be checked before planning experimental work. It is advised that a more homogeneous material is needed and that this goal should be achieved by clonal selection before transplantation.

Immunocytochemical staining of estrogen receptor in paraffin sections of human breast cancer by use of monoclonal antibody: comparison with that in frozen sections

Estrogen receptor (ER) in human breast cancer tissues was demonstrated in paraffin sections as well as in frozen sections by immunoperoxidase methods using monoclonal antibody (H222) against ER. The avidin-biotin-peroxidase complex method was used for the paraffin sections fixed in cold buffered formalin, and the peroxidase-antiperoxidase method was used for the fixed frozen sections. The results were compared with the ER content in the respective tumor tissue determined by dextran-coated charcoal assay. The specific staining for ER was located exclusively in the nuclei of cancer cells in both paraffin and frozen sections. Differences in the intensity and distribution of nuclear staining within a section were often observed, suggesting heterogeneity of the ER content of individual breast cancer cells. In 24 breast cancer tissues studied simultaneously by both paraffin and frozen section methods, 21 (88%) showed similar evaluation of the presence of ER. The results of immunocytochemical staining agreed with those of the dextran-coated charcoal assay in 89 (82%) of the 109 paraffin-sectioned tumor tissues and in 24 (86%) of the 28 frozen-sectioned tissues, indicating that ER can be demonstrated immunocytochemically by use of paraffin as well as frozen sections.

The relationship between estrogen receptors in primary and secondary breast carcinomas and in sequential primary breast carcinomas

A review of over 2000 patients who had estrogen receptors (ER) assayed in the primary breast carcinoma identified 48 cases in whom a subsequent second primary breast carcinoma or concurrent or recurrent secondary tumour had been tested for ER status. The relationship between the ER in the two specimens was as follows: Of 14 concurrent primary and secondary breast carcinomas the ER concentration was the same in 11 cases; in 1 case it was significantly higher in the primary tumour, in 2 others the reverse was observed. There was no major discordance in ER status. In 14 sequential carcinomas (after an average disease free time of 21 months), 12 pairs had identical ER status. There was major discordance of ER status in 2 cases where the secondary tumours contained ER while the primary carcinoma did not. The ER concentrations in the primary and the secondary carcinomas were comparable in 8 cases, while 3 and 5 cases had significantly higher or lower concentrations respectively in the sequential secondary tumour. In 20 cases where breast cancer developed in the contralateral breast (after an average disease-free interval of 27.7 months), essential concordance of ER status was observed in 15 of 20 sequential carcinomas. In 5 patients the first carcinoma was ER- and the second ER+; in one additional patient the first carcinoma was ER +/- and the second ER-. The ER concentrations differed significantly in 14 of the 20 bilateral carcinomas. The literature on estrogen receptor variation in breast carcinoma was reviewed.

Comparative study between histochemical and biochemical estimation of estrogen receptors in tumors

Sucrose gradient analysis (SDGC) was compared with histofluoroassay, using 17 beta-Estradiol-6-carboxymethyloxime-bovine serum albumin-fluorescein isothiocyanate (E2-BSA-FITC) as fluorescent ligand, for the estimation of estrogen receptors (ER) in human breast tumors. No correlation was seen between fluorescent ligand binding capacity by the tumoral tissues on the one hand and ER levels estimated by SDGC on the other hand. The fluorescent ligand had a lower affinity for the receptor than estradiol itself and was contaminated with free estradiol. It was concluded that the absence of correlation between both techniques was for the greatest part due to unspecific binding of E2-BSA-FITC.

Estrogen receptors in human breast cancer detected by the fluorescent estradiol histochemical and dextran coated charcoal techniques

Surgical specimens from 60 Japanese women with breast cancer were studied histochemically to detect estrogen receptors (ER). Forty-six were analyzed in a double blind study designed to compare the histochemical method using fluorescent estradiol conjugate for detection of ER (FITC method) with findings in case of the currently employed dextran coated charcoal (DCC method) techniques. The ER test was positive in 39 (65 percent) of the 60 cases studied by FITC method. Of the 46 cases analysed in a double blind study, 41 (89.8 percent) showed the same results. Of the 5 with inconsistent test results, 2 showed positive DCC and negative FITC, and 3, negative DCC and positive FITC. According to the histologic type, the FITC method demonstrated a low positive ER response rate in scirrhous cases (57 per cent), whereas the positive rate was 67 percent among papillotubular-type cases and 65 percent among medullary tubular-type cases. In relation to menstrual status, the positive rates were 68 percent and 64 percent among premenopausal and postmenopausal women, respectively. However, in relation to tumor size, no difference was noted in the positive response rate by either method. Therefore, both the DCC and FITC methods are clinically useful to determine the indications for hormone therapy.

Correlation of cell-cycle kinetics, hormone receptors, histopathology, and nodal status in human breast cancer

DNA ploidy and percent of (%S-phase) S-phase cells were determined from the DNA content distribution of 21 benign and 76 malignant (69 primary, 7 metastatic) breast tumors using flow cytometry. All of the benign tumors were diploid, whereas 89% of the malignant tumors had measurable aneuploidy. Multiple stem-lines were observed in approximately 10% of the malignant tumors. The ploidy distribution of the malignant tumors was bimodal with an increased frequency of tumors with a near diploid DNA index (DI), and a second group with DI ranging from triploid to tetraploid. The percentage of cells in S-phase ranged from less than 1% to 37.4%. DI and %S were significantly higher in poorly differentiated duct carcinomas, medullary carcinomas, and recurrent tumor metastases. DI and %S were also significantly higher in estrogen-receptor-negative tumors. There was no correlation between DI or %S and the extent of axillary nodal metastases. However, within the groups of node-negative and node-positive patients, DI and %S were not randomly distributed but were significantly correlated with degree of nuclear differentiation. Both parameters were higher in poorly differentiated tumors compared with well-differentiated tumors, indicating significant intrastage heterogeneity in tumor ploidy and proliferation characteristics. Determination of the prognostic significance of DI and %S will require a longer follow-up time.

Practical breast carcinoma cell kinetics: review and update

The S-phase fraction (SP) measured by flow cytometry of DNA and the thymidine labeling index (TLI) measured autoradiographically indicate the proportion of carcinoma cells currently synthesizing DNA and reflect the rate of proliferation. The TLI and SPF are lognormally distributed. The median TLI performed to maximize precursor uptake is near 5% (5 labeled carcinoma cells per 100) the mean near 7%, and the range from less than 1% to near 40%. Corresponding values for the SPF measured by DNA flow cytometry are slightly higher when appropriate measures are taken to reduce background debris counts and other artefacts. Residual elevation of SPF above TLI may result from S-phase arrested cells. Flow cytometric histograms show that clearly aneuploid cell lines exist in 50-80% of primary breast carcinomas. Aneuploid breast carcinomas have higher mean TLI than diploid breast carcinomas, and therefore proliferate more rapidly. They also more frequently lack estrogen receptor (ER). Carcinomas with minimal nuclear anaplasia, particularly those of tubular, mucinous, infiltrating lobular and adenocystic types have low TLI and SPF, whereas carcinomas with highly anaplastic nuclei, including medullary carcinomas, have high TLI and SPF. TLI and SPF correlate inversely with ER and PgR content, have no relationship to axillary lymph nodal status, and have a weak positive correlation with tumor size and a weak negative correlation with age. High TLI predicts a high risk of early relapse after primary therapy for both node-negative and node-positive carcinomas. Carcinomas that produce brain metastases have particularly high TLI. Current evidence suggests that high SPF and aneuploidy may prove to have prognostic significance like TLI.

Comparative flow DNA analysis of different cell suspensions in breast carcinoma

This study compared three methods of dissociation of breast lesions for DNA flow cytometry. Eleven benign lesions and 66 cancers were dissociated using mechanical, Ficoll, or enzymatic methods. DNA flow analysis showed that the DNA index did not vary from one method of dissociation to another. All benign lesions were diploid and 67% of all cancers were aneuploid. Enzymatic dissociation gave a lower percentage of aneuploid cells with a diminution of the proportion of cells in the G2 + M phase (13.2% enzymatic against 17.6% Fi-coll); on the other hand, it provided cell populations of greater viability than the other methods (32.6% enzymatic, 17.2% Fi-coll; P less than 0.01). The mechanical and Ficoll suspensions did not differ significantly when they were analyzed on the basis of their DNA content and their cellular viability. When compared with mechanical preparation, Ficoll suspension showed a lower recovery of tumor cells, but this inconvenience was compensated for by a more homogeneous aspect where the contribution of aggregates and debris was clearly lessened. Therefore, this study led us to choose Ficoll suspension for subsequent flow analysis of breast tumors.

Receptor heterogeneity of human breast cancer as measured by multiple intratumoral assays of estrogen and progesterone receptor

Multiple intratumoral tissue samples from the primary mass of 30 consecutive invasive breast cancer patients were assayed for estrogen receptor (ER) and progesterone receptor (PR) by the dextran-coated charcoal method following frozen section histopathological examination. Steroid receptor status of each sample was classified as positive (R+) or negative (R-), based only upon quantitative guide lines from the ER/PR results. Four out of 32 (12.5%) of the invasive cancers had an intratumoral sample classified as R+ and one sample as R-. R+ invasive ductal carcinomas has a highly significant degree of tubule formation (P = 0.005) when compared with R- invasive ductal cancers. While the quantitative ER content (r = 0.18) and the degree of quantitative variation in ER content (P = 0.04) did not correlate with the tumor cellularity of the individual samples, tumor cellularity (P = 0.005) and ER content (P = 0.005) were lower in the samples from the tumor border than from the central tumor samples. Variations in ER and PR content may be found on a regional basis within a breast tumor mass resulting from heterogeneity of tumor subpopulations and/or differences in tumor cellularity.

Estrogen binding sites on membranes from human laryngeal papilloma

Estrogen binding sites were identified on plasma membranes from biopsy materials (N = 16) of normal human larynx; such binding was found to be specific. In tissue from 22 cases of laryngeal papilloma, membrane binding of 17-beta-estradiol was also specific. Although such binding occurred for papilloma membranes at a comparable affinity, it was clear that all membranes from the papillomatous tissue possessed a 148% greater estrogen binding capacity; there were at least 17 times more estrogen binding sites for each mg of receptor protein on papilloma membrane than for normal laryngeal epithelium. These findings suggest a possible receptor marker for the detection and/or prediction of recurrence of laryngeal papilloma.