The evaluation of estrogen receptor in primary breast carcinoma by computer-assisted image analysis

Concurrent mutations of coding and regulatory sequences of the Ha-ras gene in urinary bladder carcinomas

This report concerns the study of Ha-ras gene mutations and ras p21 expression in primary tumors of the urinary bladder. Polymerase chain reaction-based techniques and computerized image analysis were used. The data obtained were related to tumor grade, DNA ploidy, and tumor invasion. A point mutation (G-->T) at Ha-ras codon 12 was found in 30 of 67 tumors. The mutation frequency was greater in grade III (65%) than in grade II (44%) tumors; no mutations were observed in grade I tumors. The mutation was observed more often in aneuploid (58%) than in diploid (28%) tumors. No other substitution at codon 12 was seen and no codon 61 mutation was detected. The tumors were also tested for the A-->G mutation at position 2719 of Ha-ras intron D. Concurrent codon 12 and intron D mutations were identified in seven high-grade aneuploid tumors; six were invasive. The levels of the ras gene product p21 were approximately 10 times higher in tumors with intron D mutation than in those without. These findings confirm on human bladder tumors the observations of the effect of synchronous exon-intron mutations reported on the bladder cancer cell line T24. Our results are the first demonstration of Ha-ras intron D alterations in human tumor tissues and suggest that concurrent mutations at codon 12 and intron D of this gene within the same tumor may contribute to the aggressive behavior of human bladder carcinomas.

Asymmetric distribution of oncogene products at mitosis

Computer-assisted image analysis was used to demonstrate in exponentially proliferating human tumor cells the uneven postmitotic apportionment of several oncogene-encoded proteins (ras p21; erbB-2 p185; fos p55; myc p62). This observation may provide the explanation for the high degree of heterogeneity of postmitotic cells and the asynchrony in cell cycle traverse of cultured cells.

Chromaticity analysis of immunostained tumor specimens

In order to evaluate the correlation between immunohistochemical and morphometric data on the same histological sections, we have developed a flexible color image analyzer (Microcomputer-Assisted Picture Processing System type II, MAPPS-II), and established an effective method to analyze the immunostained colorectal neoplasms based on the color recognition theory of human visual system. Colorectal adenomas and adenocarcinomas were stained with a monoclonal antibody C 12, which recognizes abnormal H antigen, using Avidin-Biotin method and diaminobenzidine (DAB, brown dye). Nuclei were stained with Hematoxylin (blue dye). Density and colorimetric analyses revealed two results: (A) Separation of immunostained brown area from blue nuclei was best performed by plotting the representative sample areas on a standard chromaticity diagram, which displays the hue and saturation of colors simulating color of human visual system. (B) After separation of immunostained areas, usual density analysis was useful for the assay of nuclear morphometric information. Using these programs, normal mucosa was negative for C 12, and showed low nuclear/cytoplasmic ratio (NCR). Adenoma was occasionally focally positive for C 12, and showed medium NCR. Carcinomas were C 12 positive, and showed high NCR. Our method permits nuclear counterstaining by hematoxylin instead of low contrast methyl green, which will widen the field of combined immunohistochemical and morphometric study.

Influence of the decrease of intracellular antigenic content on morphometric analysis: effect of the type and dilution of the first antibody

The aim of the study is to determine the effect degranulation of B cells on their immunohistochemical detection and to evaluate whether this effect depends on the technique of immunological detection. The biological model is the pancreatic insulin-containing B cell. To decrease the insulin content of the pancreas, insulin release was stimulated by five intraperitoneal injections of glibenclamide (2 mg/kg). Specimens of the pancreas were taken for insulin extraction and quantitation by radioimmunoassay (RIA), ultrastructural analyses and immunocytochemistry. The sections were treated either by polyclonal or monoclonal anti-insulin serum at various concentrations and peroxidase-antiperoxidase (PAP) technique eventually followed by silver amplification. The B-cell insular fraction or relative B-cell area (RBA) was measured with an automatic image analyser. The reference value for the relative B-cell area was established in control rats and corresponds to the ratio of the insular area occupied by immunostained B cells to the islet area. Its value was confirmed by calculation of the area occupied by non-B cells. RIA indicates a decrease of 83% of the insulin content in treated rats while the number of B granules decreases by 72% at the ultrastructural level. In usual conditions (polyclonal serum, 1/1500) the degranulation leads to a 16% underestimation of the B-cell insular fraction. This underestimation increases when monoclonal antibodies are used and further increases when higher dilutions are tested. The silver amplification does not prevent this underestimation and, in this particular model, exclusively acts by increasing the contrast. The only means of restoring the correct level of detection is to use the serum at a higher concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Estrogen receptor immunohistochemistry in carcinoma in situ of the breast

Although estrogen receptor (ER) content and its clinical significance have been extensively evaluated in invasive breast cancer, ER expression in carcinoma in situ (CIS) of the breast and its correlates are less well understood. Thus, using an indirect immunoperoxidase technique and paraffin-embedded tissue, the authors studied ER expression in 100 breast tumors containing CIS with or without invasive carcinoma. The percentages of positive and of strongly positive nuclei were compared among histologic categories of CIS and between CIS and invasive carcinoma. The relationships between histologic features of CIS (cell size, nuclear pleomorphism, necrosis, extent of CIS) the patient's age, and the ER status of CIS also were evaluated. ER expression in pure CIS was compared with that of CIS with adjacent invasive carcinoma. Significant differences were observed between comedo CIS, which was frequently ER negative, and non-comedo and lobular CIS, which usually were positive. A predominance of large cells, independently from other features, was the best morphologic predictor of ER negative status in CIS. ER in CIS correlated with ER in invasive carcinoma in 98% of cases (r2 = 0.677). CIS without invasive carcinoma was more frequently ER weak or negative than CIS associated with invasive carcinoma. There was no difference in the overall percentage of nuclear staining in CIS of women of premenopausal versus postmenopausal age; however, a higher proportion of strongly positive cells occurred in the postmenopausal group. The authors conclude that the ER expression in CIS correlates with pathologic features of differentiation and is similar to that of invasive carcinoma.

Oestrogen and progesterone receptor immunocytochemistry in human hyperplastic and neoplastic endometrium

Proliferative disorders of the endometrium may be associated with autocrine and paracrine actions between stromal and epithelial cells. To determine whether the stromal-epithelial relation with respect to oestrogen receptor (OR) and progesterone receptor (PR) is disturbed in (pre)malignant endometrium immunocytochemical OR and PR expression was quantitated by computerized image analysis. This was studied in the stromal and epithelial cells of endometrial specimens diagnosed as hyperplasia (n = 14), atypical hyperplasia (n = 16), and adenocarcinoma (n = 33). Paraffin sections were used for optimal preservation of histomorphology. A progressive loss of OR and PR content occurred with increasing malignant transformation. Stromal cells in atypical hyperplasia (P = 0.0007) and well-differentiated adenocarcinoma (P = 0.0008) exhibited a relative loss of PR content as compared with epithelial cells (P = 0.036 and P = 0.17, respectively). In atypical hyperplasia, the decrease in stromal PR content was not in parallel with persistent stromal OR immunostaining. Furthermore, stromal PR expression in atypical hyperplasia was significantly (P = 0.004) lower than in the surrounding hyperplasia, whereas the stromal OR staining as well as the epithelial OR and PR staining did not differ significantly. These observations may reflect a disturbance in hormonal interrelationships between endometrial cells in the development of endometrial neoplasia, indicating that stroma may modulate epithelial growth by paracrine mechanisms.

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)

Immunostaining of cathepsin D in breast cancer: quantification by computerised image analysis and correlation with cytosolic assay

Cathepsin-D (cath-D) was quantified in 34 breast cancer specimens by immunohistochemical staining of frozen sections with a computer image analysis and the results were compared with the corresponding cytosolic assay. Cath-D concentrations varied from 0 to 420 arbitrary units (AU). Tumour cells were more intensely stained than peritumoral tissue with the D7E3 mouse monoclonal antibody than with rabbit polyclonal antibodies. There was a good correlation (r = 0.80) between cath-D values obtained either by immunohistochemistry with D7E3 antibody or by cytosolic immunoenzymatic assay. However, with a cut-off of 50 AU, 3 out of 25 patients had higher immunohistochemical values and 2 had higher cytosolic values. Therefore, quantification of cath-D concentration in tissue section by immunostaining and a computerised image analyser, which is the only technique available for small tumours, should provide similar prognostic information to that obtained by assaying cath-D in the cytosol.

Quantitative morphology of the nervous system: expanding horizons

In this review, we show how some of the recent developments in quantitative morphology (QM) are creating exciting new opportunities for studying the structure of the nervous system. We begin with a brief overview of QM, focusing on the problems neurobiologists are likely to encounter when collecting and interpreting data from tissue sections. Many of these problems, which range from selecting a sampling method to learning the latest methods, are being solved by creating a new generation of research tools. We describe several of these new tools and show how they can be used to assemble new quantitative methods for in situ hybridization, immunocytochemistry, and camera lucida drawings. The review includes examples of how QM is being used to study the brain and concludes with a brief discussion of diagnostic pathology and its need for new quantitative approaches.

Characterization of two monoclonal antibodies against the COOH-terminal part of the human epidermal growth factor receptor and potential clinical use

Two monoclonal antibodies of the IgG2 subclass, designated A 01 and B 11, were prepared against two synthetic peptides corresponding to the COOH-terminal sequence of the human epidermal growth factor receptor (EGF-R), in order to detect EGF-R in a radioimmunometric assay and by immunohistochemistry. Characterization of these Mabs showed that they recognized two different eptiopes on the original peptides with Kd of 1.7 x 10(-8) M and 1.3 x 10(-7) M, respectively, without crossreaction. The A 431 antigen recognized by A 01 and B 11 had an apparent molecular weight of approximately 170,000 and was able to specifically link to EGF. Thus, A 01 and B 11 are directed against an antigenic site on the human EGF-R. With Western blot analysis and immunostaining, A 01 was shown to be EGF-R specific. In addition to the EGF-R, B 11 recognized two unidentified soluble proteins present in the cytoplasm of the SKBR-3 cell line but different from the c-erb B-2 oncoprotein expressed by these cells. Mabs A 01 and B 11 were used in an IRMA for the determination of EGF-R using the A 431 cell line as a source of EGF-R. Mab A 01 was also shown to be a useful tool for immunohistochemical detection of EGF-R.

A multicentre study into the reliability of steroid receptor immunocytochemical assay quantification. British Quality Control Group

Qualitative and semiquantitative assessments of oestrogen receptor and progesterone receptor positivity determined on previously immunocytochemically stained slides were performed by eight independent assessors. Concordance between assessments of steroid receptor status was good (24/25, 96%). Interassessor variations in estimates of positive immunostaining levels were high, varying by between 10 and 75% for individual slides. In 2 cases estimates for the same section ranged between 15% nuclei positive and 90% nuclei positive. Wide variations were also recorded for slides stained for progesterone receptors. Results using an assessment procedure combining staining intensity and percentage positivity estimates were also subject to marked discordance. A computerised image analysis system, also used to assess slides gave results similar to the mean manually determined percentage positivity values. It is suggested that quality control of steroid receptor immunocytochemical quantification be considered and that automated image analysis may represent an accurate and valid means of achieving this.

Comparison of microscopic imaging strategies for evaluating immunocytochemical (PAP) steroid receptor heterogeneity

Receptogram analysis was compared with three other imaging strategies for immunocytochemical assay of estrogen receptors. These included nuclear-specific methods for analysis of nuclear integrated optical density (IOD) or mean optical density (MOD) histograms, and field-specific methods, where the pixel optical density (POD) histogram was evaluated for the composite nuclear phase. Measurements in culture and in breast cancer cryosections were treated separately to isolate geometric considerations. In culture receptograms the modality of IOD and MOD histograms and their bivariate contour maps revealed one, two, or more subpopulations with discrete receptor content and concentration. However, when the field of nuclei was imaged as a whole, regardless of the number of subpopulations, POD histograms showed two minima, defining three intranuclear phases. This was due to mottling and variegation of intranuclear chromatin and nucleolar immunostaining and not to differences between nuclei. These limitations were also revealed in breast cancer sections. In POD histograms, % unstained pixels did not provide a reliable estimate of % receptor negative nuclei, as determined by their enumeration. In sections, correction of IOD for nuclear volume variability was essential to suppress artifactual peaks not representing differences in receptor content. This was achieved by multiplying nuclear IOD by the spherical nuclear radius (S) of individual slab sections. Peaks of IOD(S) then reflected receptor content on a true ratio scale. Only receptogram analysis, which incorporates these strategies, permitted objective evaluation of receptor heterogeneity at the level of tumor subpopulations.

Detection of estrogen receptors in the trigonum and urinary bladder with an immunohistochemical technique

In order to detect estrogen receptors (ER) in the female bladder, 5 premenopausal and 10 postmenopausal women affected by gynecological diseases were submitted to cystoscopy, during which both the trigonum and the bladder lateral wall were biopsied. A new, simple, cost-effective immunohistochemical technique was employed to stain the estrogen specific binding sites. ER were found in the trigonum of 3 premenopausal and 4 postmenopausal subjects, while the bladder lateral wall was always ER-negative. A comparison with previously used ER detection methods and a discussion of further hypothetical applications of the immunohistochemical technique in the study of the lower female urogenital tract are reported.

Comparison of immunocytochemical and biochemical assays for estrogen receptor in fine needle aspirates and histologic sections from breast carcinomas

An immunocytochemical assay using a monoclonal antibody specific for estrogen receptor (ER-ICA) was performed on needle aspirates and on histologic sections (mastectomy and biopsy specimens) from 55 patients with breast cancer. A total of 82 ER-ICAs were performed, with matched cytologic and histologic specimens in 27 patients, cytology alone in 15, and histology alone in 13. ER-ICA results were described by a histochemical score (H score) based on intensity-weighted percentages of staining cells. The H scores were compared with results of sucrose density gradient (SDG) analysis of histologic specimens (mastectomy, resection, or biopsy). An H score greater than or equal to 10 and an SDG value greater than or equal to 10 fmol/mg protein were considered positive. The sensitivity of cytologic ER-ICA was 94%, the specificity 100%. The sensitivity of histologic ER-ICA was 67%, the specificity 90%. Correlating cytologic H score with Black's nuclear grade showed that grade 1 (the most anaplastic) carcinomas demonstrated the lowest H scores (mean, 7.3 +/- 29.8), whereas the highest H scores were noted in grade 3 tumors (mean, 150.0 +/- 88.1). Both SDG and ER-ICA showed ER values to be lower in premenopausal than postmenopausal women. There was no correlation between H score and presence of axillary nodal metastases or tumor size. An overall good correlation was demonstrated between immunohistochemical methods and biochemical analysis.

Quantitative imaging of immunocytochemical (PAP) estrogen receptor staining patterns in breast cancer sections

"Receptogram Analysis" has been developed as a pattern-oriented approach for predicting endocrine response in breast cancer based upon quantification of the estrogen receptor immunocytochemical assay (ERICA), using a Quantimet Imaging System. Response prediction was evaluated in 58 stage III and IV patients receiving endocrine therapy (primarily Tamoxifen). The Receptogram is a composite of the univariate distributions of nuclear receptor content, IOD(S), and concentration (MOD), and their bivariate contour plot; where (S) is the calculated nuclear radius in section. MOD distributions were classified into four types based upon peak modality and kurtosis (I-IV), and contour plots were classified into four subtypes (A-D) based upon contour slope. Patients failing therapy were ERICA--or their receptogram revealed co-existent ER+ and ER- tumor cells (type II), highly skewed MOD distributions lacking defined peaks (type IV), or contours with nearly horizontal slope (type C). Response was realized in 9/16 type I patients, with a single positive MOD peak, and in 9/15 type III patients, with discrete, multimodal MOD peaks. In contrast, 0/8 type II, 0/12 type IV, and 0/10 type C patients were responders. Receptogram analysis was superior to cytosol assay (DCC) as a response discriminant: positive predictive value, 53% vs. 33%; negative predictive value, 100% vs. 75%; sensitivity, 100% vs. 83%; specificity, 68% vs. 23%; and accuracy, 78% vs. 41%, respectively. Alternately, patients were assigned to potentially responsive or non-responsive groups based upon thresholded mean receptor parameters: field MOD, mean nuclear MOD (NMOD), and mean NMOD(PF) where PF is the ER+ nuclear fraction. While these parameters correlated with DCC (r = .72, 0.69, and 0.69), they were only marginally better in predictive value.

Assessment of oestrogen receptor content of breast carcinoma by immunohistochemical techniques on fixed and frozen tissue and by biochemical ligand binding assay

The oestrogen receptor content of 61 breast carcinomas was assessed by biochemical ligand binding assay and three immunohistochemical techniques--a frozen section method (Abbott ER-ICA) and on paraffin wax sections after fixation by two methods. The two fixatives used were Carson's buffered formalin and methacarn, and a DNAse pretreatment of sections was used. Overall agreement for the immunohistochemical methods with the ligand binding technique were 95%, 85%, and 86% for the frozen, formalin, and methacarn methods, respectively. A semiquantitative staining score was performed and all three methods gave significant correlations of staining scores with biochemical ligand binding values. The frozen section method was best (r = 0.88) with the fixed tissue methods yielding poorer correlation coefficients. Several factors affected staining, including the nature of the fixative and variable activity of DNAse. It is concluded that immunohistochemical assessment of oestrogen receptor content on fixed tissue provides acceptable qualitative information but that standardisation of protocols for tissue processing will be necessary for optimal utility and especially for quantitative assessments.

Studies of the HER-2/neu proto-oncogene in human breast and ovarian cancer

Carcinoma of the breast and ovary account for one-third of all cancers occurring in women and together are responsible for approximately one-quarter of cancer-related deaths in females. The HER-2/neu proto-oncogene is amplified in 25 to 30 percent of human primary breast cancers and this alteration is associated with disease behavior. In this report, several similarities were found in the biology of HER-2/neu in breast and ovarian cancer, including a similar incidence of amplification, a direct correlation between amplification and over-expression, evidence of tumors in which overexpression occurs without amplification, and the association between gene alteration and clinical outcome. A comprehensive study of the gene and its products (RNA and protein) was simultaneously performed on a large number of both tumor types. This analysis identified several potential shortcomings of the various methods used to evaluate HER-2/neu in these diseases (Southern, Northern, and Western blots, and immunohistochemistry) and provided information regarding considerations that should be addressed when studying a gene or gene product in human tissue. The data presented further support the concept that the HER-2/neu gene may be involved in the pathogenesis of some human cancers.