Photometric behavior of comet Hale-Bopp (C/1995 O1) before perihelion.

Narrowband photometric observations of comet Hale-Bopp (C/1995 O1) between 25 July 1995 and 15 February 1997 indicated gas and dust production rates of 20 and 100 times greater, respectively, than observed at the same heliocentric distances for comet P/Halley in 1985. Hale-Bopp produced dust at a rate greater than has been observed for any other comet at any distance since at least 1977. On the basis of the observed production rate of the hydroxyl molecule, the calculated minimum effective diameter of Hale-Bopp's nucleus is 17 kilometers, but the actual diameter of the nucleus is likely to be at least two to three times larger. The chemical composition of Hale-Bopp is consistent with that of other long-period comets originating from the Oort Cloud.

Association of GNB3 C825T polymorphism with peak oxygen consumption.

The C825T single nucleotide polymorphism (SNP) in the guanine nucleotide-binding protein, beta polypeptide 3 ( GNB3) gene gives rise to a splice variant, GNB3s that has enhanced G protein activation and signal transduction activity. This variant has been reported to be associated with cardiovascular disease, diabetes and obesity. We studied this SNP in 95 healthy 18 to 30 year-old African American university students to determine its association with aerobic capacity and cardiorespiratory fitness as measured by peak oxygen consumption (VO (2)peak). We also tested the effect of heart rate variability (HRV) as an independent predictor of VO (2)peak. We tested the association of the SNP and HRV with VO (2)peak in a multivariate regression analysis with appropriate adjustments of covariates, under dominant and recessive models. We found a significant independent association of the 825T allele with VO (2)peak under the dominant model (beta-coef.=-0.101, P=0.0442). We also observed that HRV marginally influenced VO (2)peak. This finding suggests that GNB3 C825T polymorphism is associated with VO (2)peak which is influenced by autonomic modulation of heart rate in African Americans.

Primary human breast carcinomas transplantable in the nude mouse.

Of 19 primary human breast carcinomas implanted into noninbred female nude mice, 3 produced transplantable tumors. Membrane components specific for human mammary epithelial cells were demonstrated in the cells from heterotransplants even after four or five passages in nude mice.

Development and characterization of breast cancer reactive monoclonal antibodies directed to the core protein of the human milk mucin.

A mucin molecule, which has a molecular weight of greater than 400,000 and which carries tumor associated epitopes recognized by monoclonal antibodies HMFG-1 and HMFG-2, has been purified from human skimmed milk by affinity chromatography followed by passage through a size exclusion column. While treatment of the mucin with hydrogen fluoride for 1 h at 4 degrees C removed the peripheral oligosaccharides, treatment with HF for 3 h at room temperature removed all of its lectin binding ability and revealed a dominant polypeptide of about 68,000. This appears to be the size of the mucin core protein. Monoclonal antibodies have been developed that react with the stripped and partially stripped molecule but not with the intact mucin. From the initial screening on histological sections one of these antibodies, SM-3, reacts with 91% of breast carcinomas but shows little or no reactivity on benign mammary tumors, normal resting, pregnant, or lactating breast. It appears that this monoclonal antibody is reacting with an epitope that is usually masked by oligosaccharide moieties in normal cells but which is exposed, perhaps due to aberrant glycosylation, in malignant cells.

Histochemical studies with an estrogen receptor-related protein in human breast tumors.

The histochemical characteristics of a Mr 29,000 phosphoprotein related to estradiol receptor are described in a large series of human breast tumors. The antigen was detected with a monoclonal antibody (D5) raised against partially purified human myometrial estradiol receptor. An indirect immunoperoxidase method was used with methacarn-fixed, wax-embedded sections. Quantitation of staining and its reproducibility are described. Results with trucut biopsies agree with those obtained with larger tumor sections. Normal breast is infrequently positive. Histochemical staining is higher in invasive carcinoma than in normal breast with ductal carcinoma in situ adjacent to infiltrating tumors exhibiting intermediate values. Furthermore, most in situ carcinomas have a heterogeneous staining pattern. About 20% of invasive tumors also exhibit heterogeneity. No simple correlation is seen between staining and histological grade. There are more low-staining tumors in young (less than 50 yr old) patients than in older women. Staining correlates with levels of cytosol estradiol receptor but not cytosol progesterone receptor. However, cytosol estradiol receptor-negative, cytosol progesterone receptor-positive tumors tend to have positive Mr 29,000 phosphoprotein levels. Positive staining is associated with a higher response rate to hormone therapy (50%). None of the negative tumors responded to hormone treatment. With these patients, comparison of histochemical assay for Mr 29,000 phosphoprotein and [3H]estradiol binding assays indicated that the former was at least as good as the latter assay in predicting hormone response. About 20% of cytosol estradiol receptor-positive tumors have low Mr 29,000 phosphoprotein, and such tumors have poor response to hormone treatment.

Histochemical studies with a monoclonal antibody raised against a partially purified soluble estradiol receptor preparation from human myometrium.

A monoclonal antibody (D5) raised against affinity-purified cytosol estradiol receptor (REC) from human myometrium has been used to stain human tissues by means of an indirect immunoperoxidase method. Good staining was obtained with ethanol-, glutaraldehyde-, or Carnoy's-fixed material but not with formalin or Bouin's fixation. Cytoplasmic staining of human breast tumors exhibited a highly significant correlation (P less than 0.001) with REC assayed by conventional estradiol-binding assay provided that allowance was made for both staining intensity and cellularity of the tumor; no correlation existed with soluble progesterone receptor content. Both patient age and tumor differentiation influenced staining patterns in the same way as did REC content. Cultured REC-positive human breast tumor cell lines (MCF-7, ZR-75-1, and CA-2) showed positive staining as did cultured epithelium from human milk. Epithelia in normal breast and fibroadenoma exhibited variable staining that rarely reached the intensity seen in REC-positive tumor cells. The staining patterns of human normal endometrium, myometrium, fallopian tube, ectocervix, endocervix, and ovary and neoplastic endometrium and ovary are described. In every situation thus far examined only cytoplasmic staining has been observed.

Loss of heterozygosity mapping at chromosome arm 16q in 712 breast tumors reveals factors that influence delineation of candidate regions.

Loss of heterozygosity (LOH) at the long arm of chromosome 16 occurs in at least half of all breast tumors and is considered to target one or more tumor suppressor genes. Despite extensive studies by us and by others, a clear consensus of the boundaries of the smallest region of overlap (SRO) could not be identified. To find more solid evidence for SROs, we tested a large series of 712 breast tumors for LOH at 16q using a dense map of polymorphic markers. Strict criteria for LOH and retention were applied, and results that did not meet these criteria were excluded from the analysis. We compared LOH results obtained from samples with different DNA isolation methods, ie., from microdissected tissue versus total tissue blocks. In the latter group, 16% of the cases were excluded because of noninterpretable LOH results. The selection of polymorphic markers is clearly influencing the LOH pattern because a chromosomal region seems more frequently involved in LOH when many markers from this region are used. The LOH detection method, i.e., radioactive versus fluorescence detection, has no marked effect on the results. Increasing the threshold window for retention of heterozygosity resulted in significantly more cases with complex LOH, i.e., several alternating regions of loss and retention, than seen in tumors with a small window for retention. Tumors with complex LOH do not provide evidence for clear-cut SROs that are repeatedly found in other samples. On disregarding these complex cases, we could identify three different SROs, two at band 16q24.3 and one at 16q22.1. In all three tumor series, we found cases with single LOH regions that designated the distal region at 16q24.3 and the region at 16q22.1. Comparing histological data on these tumors did not result in the identification of a particular subtype with LOH at 16q or a specific region involved in LOH. Only the rare mucinous tumors had no 16q LOH at all. Furthermore, a positive estrogen content is prevalent in tumors with 16q LOH, but not in tumors with LOH at 16q24.3 only.

Node-negative breast cancer: prognostic subgroups defined by tumor size and flow cytometry.

Adjuvant systemic therapy for women with node-negative breast cancer is most easily justified for those patients at highest risk of relapse. We have examined the impact of tumor size, histologic grade, estrogen receptor (ER) status, tumor ploidy, and S-phase fraction (SPF) on relapse-free survival (RFS) for 169 patients with node-negative breast cancer in order to identify groups of patients at high and low risk of relapse. Patients with small tumors (less than or equal to 1.0 cm) had a significantly better RFS than those with larger tumors (P = .005), with 96% remaining relapse-free at 5 years. Patients with tumors less than or equal to 1.0 cm were thus excluded from analysis when attempting to define a group with a poor prognosis. Within the group of patients with tumors greater than 1.0 cm, tumor ploidy (P = .63), ER status (P = .3), or progesterone receptor (PgR) status (P = .24) did not predict for RFS. Patients with grade 1 or 2 infiltrating ductal tumors had a significantly better prognosis than those with grade 3 tumors (P = .04). The prognostic factor that gave the widest separation between subgroups, however, was SPF. Patients whose tumors were greater than 1.0 cm with an SPF less than or equal to 10% had a 5-year RFS of 78% compared with a 5-year RFS of 52% for those with an SPF greater than 10% (P = .006). We have combined tumor size and SPF to identify three prognostic groups: (1) tumor less than or equal to 1.0 cm, 5-year RFS 96%; (2) tumor greater than 1.0 cm plus SPF less than or equal to 10%, 5-year RFS 78%; 3) tumor greater than 1.0 cm plus SPF greater than 10%, 5-year RFS 52%. These prognostic groupings may help identify patients most suitable for adjuvant therapy.

The interaction of oestrogen receptor status and pathological features with adjuvant treatment in relation to survival in patients with operable breast cancer: a retrospective study of 2660 patients.

The oestrogen receptor (ER) status of 2660 patients with primary breast cancer has been related to the effect of different adjuvant systemic therapies on survival. However, as patients in the various treatment groups also had different prognostic features comparison between treatments was difficult. Over 90% of patients receiving tamoxifen (Tam) were postmenopausal compared with <20% of those receiving chemotherapy (CT). The latter had more positive nodes (85% vs 54%) and grade III tumours (54% vs 30%) than the Tam group. The combined CT and Tam group had similar characteristics to the CT alone group. The current reported increase in the proportion of women with ER+ tumours is explained by immunohistochemical analysis of ER and screening programmes. ER status was unrelated to survival in patients with small, low grade, node-negative tumours which was no different from that expected for age-matched women taken from the general population. The value of adjuvant treatment in these patients is therefore questionable. In those given any adjuvant treatment, survival of women with ER+ tumours was prolonged, with the greatest effect being seen in those receiving Tam. Patients with ER- tumours benefited from CT but the addition of Tam to CT improved survival only in those with ER+ tumours. ER status is now established as a major predictive factor for treatment selection in primary disease. Studies of prognostic and predictive markers may be invalidated by use of adjuvant therapy and selection criteria for different treatments. Survival will be influenced by both tumour biology and therapy. This important consideration must be remembered when analysing new markers, particularly in small studies.

c-erbB-3 protein expression in ductal carcinoma in situ of the breast.

c-erbB-3, A recently identified member of the type I tyrosine kinase receptor family, has been shown to be overexpressed in invasive ductal carcinoma of breast. In this study, expression of the c-erbB-3 protein was examined in 57 cases of pure ductal carcinoma in situ of the breast (DCIS) by immuno-cytochemical methods. Staining was either absent (17 cases), present at levels equivalent to that found in adjacent normal tissue (20) or greater than in normal tissue (20). In most cases the pattern of staining was cytoplasmic, but in 4 cases with the most intense reaction there was also focal membrane staining. In the same series of cases, c-erbB-2 protein had previously been shown to be overexpressed in 28 of 57 cases, c-erbB-2 overexpression was correlated with normal level of c-erbB-3, and lack of c-erbB-2 expression was correlated with c-erbB-3 overexpression.

Proliferative activity, histological grade and benefit from adjuvant chemotherapy in node positive breast cancer.

The influence of S-phase fraction (SPF), measured by DNA flow cytometry, and histological grade on outcome following adjuvant chemotherapy was analysed for 214 patients with node positive breast cancer treated at Guy's Hospital who were entered into the Guy's/Manchester trial of combination chemotherapy with cyclophosphamide/methotrexate/5-fluorouracil (CMF) vs. no adjuvant treatment. Adjuvant CMF significantly improved relapse-free survival (RFS) for premenopausal patients whose tumours had an SPF of 10% or less (control vs. CMF, P = 0.05) and premenopausal patients whose tumours had an SPF over 10% (control vs. CMF, P = 0.003). No significant improvement in RFS attributable to CMF was seen for either subgroup of postmenopausal patients. When patients were divided into subgroups based on histological grade of tumour, an improvement in RFS attributable to CMF was seen for premenopausal patients with well differentiated (grade 1 or 2) tumours (control vs. CMF, P = 0.03) and premenopausal patients with poorly differentiated (grade 3) tumours (control vs. CMF, P = 0.006). Again, no improvement in RFS was noted for any subgroup of postmenopausal patients defined by tumour grade.

Increased use of immunohistochemistry for oestrogen receptor measurement in mammary carcinoma: the need for quality assurance.

This paper outlines the changes which have occurred over the last 25 years in the methods employed for the measurement of oestrogen receptors to aid the management of women with breast cancer. Immunohistochemistry is now the method of choice and knowledge of oestrogen receptor status is being used with increasing frequency for the selection of adjuvant treatment as well as for the treatment of metastatic disease. It is essential that good quality assurance procedures are established so that results are reproducible and can be used with confidence in individual centres as well as being comparable with those produced elsewhere. A retrospective study of 170 women with metastatic breast cancer provides the basis for a discussion on the advantages and pitfalls of the immunohistochemical assay. Particular emphasis is paid to the choice of cut-off and how the results may be applied in patient management.

Tumour grade does not change between primary and recurrent mammary carcinoma.

The primary tumour grade in 115 patients with infiltrating ductal carcinoma of the breast was compared with the type of the ductal carcinoma in situ (DCIS) component and with the grade of 169 locally recurrent and metastatic lesions. 102 patients had axillary lymph node metastases at the time of primary surgery, 49 had subsequent recurrences and 36 had both. There was concordance of grade between the primary tumour and axillary lymph node metastases and with subsequent locally recurrent and metastatic lesions. The type of the DCIS component was also significantly associated with the grade of the infiltrating component. No evidence of progression of tumour grade between these phases of mammary carcinoma was found.

Patterns of metastatic breast cancer in relation to histological type.

We have examined the clinical records fo 1238 patients with operable breast cancer to identify the sites of metastatic disease. Infiltrating ductal carcinoma (IDC) recurred more commonly in lung (P < 0.05), pleura (P < 0.05) and brain (P < 0.05), while infiltrating lobular carcinoma (ILC) more commonly metastasised to the bone marrow (P < 0.01) and peritoneum (P < 0.01). Bone involvement as the initial presentation of distant metastatic disease occurred in over 50% of women with ILC, significantly more commonly than in those with IDC (34%, P < 0.01). Survival was similar for the two groups, both from time of diagnosis and from time of development of distant metastases.

Cyclical tumour variations in premenopausal women with early breast cancer.

The hormonal milieu at the time of tumour excision may have a significant impact on survival in premenopausal patients with breast cancer, with those undergoing surgery between days 3 and 12 of the menstrual cycle having a worse prognosis. To investigate possible mechanisms which might explain this finding, histological features of tumours from 363 patients included in two studies from Guy's Hospital have been reviewed. Axillary nodal involvement occurred in 71/115 (62%) of patients whose primary tumour was excised between days 3 and 12 of the cycle, compared with 116/248 (47%) of patients undergoing surgery at other phases of the cycle (chi 2 = 7.04, P < 0.01). Vascular invasion was observed in 54/115 (47%) of primary tumours removed between days 3 and 12 and 82/248 (33%) of tumours removed at other times (chi 2 = 6.47, P < 0.02). Multivariate analysis of factors influencing survival indicated that both axillary nodal status and phase of the cycle were highly significant independent predictors of prognosis.

Overexpression of the c-erbB-2 oncoprotein: why does this occur more frequently in ductal carcinoma in situ than in invasive mammary carcinoma and is this of prognostic significance?

Overexpression of c-erbB-2 occurs in 60% of in situ and 25% of infiltrating ductal carcinomas. We have previously found very strong associations between immunohistochemical staining for c-erbB-2 and histological pattern and nuclear size in ductal carcinoma in situ (DCIS) and less strong correlation with proliferative activity. In a further study of infiltrating ductal carcinomas we have found that, in addition to tumours arising from c-erbB-2 positive, large celled, rapidly proliferating, comedo carcinomas and c-erbB-2 negative small celled cribriform/micropapillary carcinomas with a low proliferative rate, there is a third group of c-erbB-2 negative tumours with large nuclei and variable proliferative activity. These latter tumours are not seen in pure DCIS suggesting that they have a very transient in situ stage. Therefore, although in pure DCIS c-erbB-2 positively appears to be associated with tumours with a greater invasive potential, and c-erbB-2 negativity with tumours having a more favourable prognosis, the latter is not necessarily true in infiltrating disease.

Immunochemical analysis of the p53 oncoprotein in matched primary and metastatic human tumours.

There is much interest in the range of genetic aberrations which occur in human malignancies. An immunohistochemical study has been carried out to investigate the consistency of expression of abnormally accumulated p53 protein in paired samples of archival primary and metastatic carcinomas. The staining of methacarn-fixed tissue from 136 matched pairs of mammary carcinoma and 20 cancers from other sites was completed using antibody CM-1 and DO1 in a sensitive peroxidase-conjugated streptavidin-biotin technique. The majority of tumour cells were positive in 25% and the tumours were negative in 17% of the primary carcinomas; staining was heterogeneous in the remaining cases. Staining was identical in 180/186 (96%) metastatic lesions. An ELISA assay carried out on 12 matched pairs of the tumour specimens demonstrated that altered conformation of the aberrant p53 protein present in a primary lesion was maintained in its metastasis. These data indicate that alterations in the p53 gene result in a relatively stable phenotype and that progression of disease is not usually accompanied by either further mutation or loss of the mutant allele.

Acantholytic variant of squamous-cell carcinoma of the breast.

Three cases of acantholytic squamous-cell carcinoma of the breast are reported. They all had histological features resembling those of angiosarcoma or adenocarcinoma. They were not angiosarcoma, since in all three cases areas of squamous differentiation were present; in addition, the neoplastic cells were negative when stained for factor VIII, but were positive with anti-epidermal keratin. The glandular pattern exhibited, especially in Case 2, was difficult to differentiate from that of an ordinary carcinoma. However, the presence of dyskeratotic cells within the lumina, and the absence of alcian blue/periodic acid-Schiff positive material, and epithelial membrane antigen staining, were evidence against the diagnosis of adenocarcinoma. The patients died 5, 6, and 16 months after the diagnosis. Tumors with these histological features may have a very aggressive clinical course.

Microglandular adenosis, apocrine adenosis, and tubular carcinoma of the breast. An immunohistochemical comparison.

Four cases of microglandular adenosis (MA), together with four cases of apocrine adenosis (AA) and 10 cases of tubular carcinoma (TC) of the breast were studied at the light and immunohistochemical level. One case of MA was studied with electron microscopy. MA is characterized by an absence of myoepithelial cells (ME), epithelial membrane antigen (EMA), and gross cystic disease fluid protein (GCDFP-15). The absence of EMA in MA makes it unique among benign glandular hyperplasias of the breast. AA contains myoepithelial cells and a distinct basal lamina. It is characterized by the presence of GCDFP-15, the specific apocrine marker, which is not present in MA. TC lacks both myoepithelial cells and a basal lamina. It is negative for GCDFP-15. Periductal and vascular elastosis are common and usually prominent, whereas they are not found in either MA and AA. Other stromal changes further distinguish the three lesions. These three distinct entities can be separated objectively and unequivocally and it is essential that this be done so as to prevent confusion.