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B M Ljung

Publications and source records attributed to B M Ljung.

At least 19 recordsLinked to original sources
PubMed1995

Tumor angiogenesis as a prognostic assay for invasive ductal breast carcinoma.

BACKGROUND: Tumor angiogenesis, as assayed by microvessel density, has been proposed as an independent prognostic marker for clinical outcome in breast cancer patients. PURPOSE: The present study evaluated the microvessel density assay and assessed its utility, alone and together with the evaluation of other tumor characteristics, in predicting outcome in patients with invasive ductal carcinomas. METHODS: In a blinded design, cases of invasive ductal carcinoma were selected from a registry containing the records of and tumor specimens from 386 breast cancer patients treated at the Massachusetts General Hospital from 1977 through 1982. After the exclusion of ineligible patients and inadequate specimens, 220 patients were included in the study; their median time of follow-up was 11.5 years. Half of these patients (n = 110) were positive for axillary lymph node metastases. Histologic sections of the tumors were stained immunocytochemically for factor VIII, a coagulation protein expressed by blood vessel endothelium, and for p53 protein. Independently, two analysts counted microvessels in three microscope fields selected from separate vascular regions of the tumor. Variability in microvessel scores between analysts and among different fields of the same tumor was summarized by the coefficient of variation. The kappa statistic tested for agreement between the analysts while correcting for chance agreement. The effects of tumor characteristics on metastasis-free survival and overall survival were tested univariately by the Harrington-Fleming rank test procedure. The effect of multiple factors on survival was tested under a Cox multivariate proportional hazards model. RESULTS: Microvessel count showed considerable variability between the two analysts and among regions within each tumor, with an overall concordance for tumor classification of 73%. Univariate analysis revealed no association between microvessel count and any other tumor or patient characteristic. Multivariate analysis indicated, for these patients, that nodal status and p53 staining predicted metastasis-free survival and that nodal status, estrogen receptor (ER) status and tumor grade predicted overall survival. CONCLUSIONS: Microvessel count showed much variation among different regions of each tumor. It did not predict metastasis-free survival or overall survival. Nodal status was the most powerful criterion to stratify these patients with invasive ductal carcinoma of the breast into different survival groups. Only ER status, tumor grade, and p53 staining had additional prognostic utility for these patients after they had been stratified by nodal status.

Analysis of Variance↗
PubMed1994

Fine needle aspiration techniques for the characterization of breast cancers.

Fine needle aspiration biopsy (FNAB) is a well established method for diagnosing breast lesions, including cancers. FNAB does not require surgery and uses only a small amount of material. FNAB can also be used to acquire material for special studies. This is especially useful with small tumors (< or = 1 cm) when most of the material is needed to make a histologic diagnosis. Immunostaining techniques can be used on FNABs to investigate proliferation by bromodeoxyuridine uptake or Ki-67 labeling. Immunostaining techniques can also be used to identify oncoprotein expression, such as of p53. Fluorescence in situ hybridization is a technique that can be used to gather cytogenetic information directly from interphase tumor cells and is well suited for use with FNAB material because the harvested nuclei are intact and no cumbersome dissociation processing is needed. Flow cytometric techniques can be applied to FNAB material to study DNA content and S-phase fraction. Material acquired by FNAB can also be analyzed by the polymerase chain reaction followed by mutation detection. In this report, the authors show the applicability of these various analytic approaches to FNAB material from primary breast cancers. They show that it is essential that the FNAB harvest is representative, ample, and well prepared for the success of these studies.

Biopsy, Needle↗
PubMed1994

Deletion of two separate regions on chromosome 3p in breast cancers.

We have characterized the copy number of various loci on chromosome 3p in a series of breast cancers. To determine the precise region(s) involved, restriction fragment length polymorphism (RFLP) analysis for loss of heterozygosity (LOH) was performed using a panel of RFLP probes at 3p13-14, 3p21-22, and 3p24-26. The incidence of LOH at the three loci was 41, 32, and 45%, respectively. To validate the LOH data and to gain insights into the mechanisms resulting in LOH, chromosome 3 pericentromeric and 3p region-specific DNA probes were used to determine the DNA copy number by fluorescence in situ hybridization (FISH). Among 22 cases examined, 15 showed loss by both LOH and FISH, indicating that the dominant mechanism of LOH at 3p in breast cancer is a physical deletion. Two of the 22 cases showed loss by RFLP analysis but not by FISH, suggesting either mitotic recombination or loss and endoreduplication. In three cases, RFLP analysis indicated allelic imbalance, which was incorrectly interpreted as LOH, since a gain of one allele was suggested by FISH. By constructing a deletion map, we found that 2 separate regions, 3p13-14 and 3p24-26, were independently deleted in some breast cancers. Additionally, four cases had break points within the 3p24-26 region and one case had a homozygous deletion at 3p13, further supporting the hypothesis that there are tumor suppressor genes at both 3p13-14 and 3p24-26. Although high frequency of LOH was observed at the 3p21-22 region, there was no direct evidence supporting the existence of a breast cancer tumor suppressor gene there as opposed to codeletion with either the proximal or distal region.

Blotting, Southern↗
PubMed1994

The urokinase receptor is expressed in invasive breast cancer but not in normal breast tissue.

We have studied expression of the urokinase receptor (u-PAR) in paraffin-embedded breast tissues at various stages of malignant progression. Forty-nine of 59 invasive cancers studied showed varying degrees of reactivity with our polyclonal antibody. The staining pattern was variable from case to case, although strong surface staining of tumor-associated macrophages was evident in most of these sections. In several cases, blood vessels in selected tumor areas were stained, as confirmed by treatment of adjacent sections with an anti-factor VIII antibody. These could represent regions of recent angiogenesis. Staining of tumor cells was observed in 21 of 59 cases and was extensive in 5 cases but confined to a small percentage of cells in the remaining 16 samples. In contrast with the cancer sections, all normal breast tissue (12 cases) was negative, as well as all fibroadenomas (4 cases), papillomas (5 cases), and hyperplasia with atypia (2 cases) studied. Seven carcinomas in situ examined were also negative for u-PAR, with the exception of few macrophages in two cases, suggesting that u-PAR expression may be associated with invasive tumor. The presence of u-PAR in human breast cancer and its absence from nonmalignant breast tissue supports the idea that plasminogen activation plays an important role in the process of cancer invasion. Expression of u-PAR on macrophages, endothelial cells, and cancer cells suggests the existence of complex paracrine interactions between tumor cells and stroma.

Base Sequence↗
PubMed1994

Loss of heterozygosity and p53 gene mutations in breast cancer.

Immunopositivity for the p53 tumor suppressor gene product was evaluated in 133 breast cancers and compared to loss of heterozygosity (LOH) at various chromosomal loci. The validity of p53 immunopositivity as an indicator for p53 mutations was verified using two molecular assays of p53 mutations: single stranded conformational polymorphism (32 cases) and/or direct sequencing (14 cases). Immunopositivity was highly specific for mutations, since all of 15 strongly immunopositive tumors (> 10% of the cells are positive) and seven of nine cases with borderline immunopositivity had mutations by molecular analysis but were somewhat lower in sensitivity, p53 mutations being also detected in three of 23 (13%) immunonegative cases. LOH was measured at loci on the following chromosomes (1p,q; 2p; 3p; 7q; 11p,q; 13q; 16q; 17p; 18p,q; and 22q) by Southern blotting, polymerase chain reaction amplification of restriction fragment length polymorphisms, or repetitive cytidine and adenine stretches (CA repeats). There was no association between p53 mutations and one measure of genomic instability, namely, high incidence of overall LOH. In contrast, p53 mutations strongly associated with LOH at two specific loci, 3p24-26 (P < 0.001) and 7q31 (P < 0.05). There was no association between p53 mutations and LOH at 17p (site of the p53 gene), suggesting that breast cancers often have only one defective allele of the p53 gene.

Base Sequence↗
PubMed1994

Benign and malignant papillary lesions of the breast. A cytomorphologic study.

Fine-needle aspiration cytology of benign and malignant papillary lesions of the breast has been infrequently described. To define the cytologic features of benign and malignant papillary breast lesions better, the authors retrospectively reviewed the fine-needle aspiration cytology of five cases of histologically proven intracystic papillary carcinoma (IPC) and six cases of histologically proven papilloma. Clinical information was obtained from the medical records in each case. Intracystic papillary carcinoma tended to present as a larger tumor (average, 5 cm) in older women (average, 65.4 years). Papilloma, however, tended to present as a smaller tumor (average, 1.5 cm) in younger women (average, 43 years). Eighty percent of the IPC cases (4/5) and 50% of the papilloma cases (3/6) yielded highly cellular aspirates with complex vascular papillae and single columnar cells. Macrophages were a constant feature of IPC and were present in all but one case of papilloma. Although cellular atypia was not a prominent feature in either IPC or papilloma, moderate atypia was noted in one case of IPC and two cases of papilloma. Severe atypia was noted in a single case of IPC. Although IPC tended to yield a harvest with higher cellularity and single intact cells, no single feature or constellation of findings was consistently reliable in distinguishing IPC from papilloma. The authors found that papillary lesions of the breast demonstrate a distinct cytomorphology characterized by complex vascular papillae, columnar cells, and macrophages. They concluded, however, that, in the absence of overt cytologic malignancy, distinguishing between benign and malignant papillary breast lesions is difficult, if not impossible.

Adult↗
PubMed1994

Fine needle aspiration biopsy for diagnosis and follow-up of prostate cancer. Consensus Conference on Diagnosis and Prognostic Parameters in Localized Prostate Cancer. Stockholm, Sweden, May 12-13, 1993.

Fine needle aspiration biopsy (FNAB) and ultrasound-guided core biopsy using biopty gun both have a high, and approximately equal, accuracy in diagnosing and grading prostate cancer. The TRUS-guided technique provides a better estimation of the tumor extent and to some degree even of capsular involvement. It is therefore a recommendable part of the preoperative evaluation when radical prostatectomy is contemplated. On the other hand, the aspiration technique usually provides more epithelial cells. It entails a significantly lower risk of septic complications and of seeding tumor cells. It has also a lower cost than the core biopsies. The aspiration biopsy can easily be performed repeatedly in the follow-up procedure, which is of particular importance in cases managed with watchful waiting. We recommend the aspiration biopsy for routine use in the diagnostic work-up and follow-up. It is essential that not only the cytologic evaluation but as well the sampling from the prostate is performed with adequate expertise.

Biopsy, Needle↗
PubMed1994

Cell proliferation in hyperplastic and in situ carcinoma lesions of the breast estimated by in vivo labeling with bromodeoxyuridine.

The proliferative activity of normal, benign proliferative, and carcinoma in situ (CIS) breast lesions was studied by in vivo labeling with 5-bromodeoxyuridine (BrdU) in 35 patients with concurrent breast carcinoma. The BrdU-labeled cells were identified on histologic sections by an anti-BrdU monoclonal antibody and an immunoperoxidase reaction. The percentage of BrdU-labeled cells in nonatypical hyperplasia (NAH) was higher (1.15 +/- 1.14%) than normal epithelial cells (0.67 +/- 0.56%, p = 0.066, borderline significance). This difference was very significant in postmenopausal women and disappeared in premenopausal women. No significant difference was found in the fraction of proliferating cells between NAH and atypical hyperplasia (AH): 1.15 +/- 1.14% for NAH versus 1.26 +/- 1.19% for AH. In CIS and in invasive carcinoma (ICA), a significant increase in the percent of BrdU-labeled cells was observed when compared to the normal epithelial cells or NAH (p < 0.001). No significant difference was found in the values of BrdU-labeled cells between CIS and ICA (p = 0.29). The percent of BrdU-labeled cells in benign breast lesions, including fibroadenoma, papilloma, and sclerosing adenosis, did not differ from those of the normal epithelial cells. The menopausal status of the patients did not affect the proliferative activity in NAH or CIS. No correlation was found in the fraction of BrdU-labeled cells between the normal and hyperplastic epithelial cells (r2 = 0.012) or between NAH and CIS (r2 = 0.406) or between CIS and ICA (r2 = 0.429).

Adult↗
PubMed1994

The association of p53 immunopositivity with tumor proliferation and other prognostic indicators in breast cancer.

Abnormal accumulation of the p53 tumor suppressor gene product was analyzed in 198 primary invasive human breast carcinomas. In 47 of these cases, single-strand conformational polymorphism was used to detect mutations in the highly conserved exons 5-9 of the gene. Mutations as determined by single-strand conformational polymorphism were found in 15 of 15 strongly immunopositive cases (100%) and 3 of 23 immunonegative cases (13%). There were also nine cases with < 1% immunopositive cells (borderline immunopositivity); p53 mutations were detected in seven of these cases. The results suggest that p53 immunopositivity is a highly specific, albeit somewhat insensitive surrogate for p53 mutations. p53 accumulation, detected by immunohistochemical methods using antibody PAb 1801, was noted in 29.8% of the cases and was associated with estrogen receptor (ER) negativity (P = 0.0003), progesterone receptor (PR) negativity (P = 0.008), and high histological grade (P = 0.037) by univariate analysis. Incorporation of bromodeoxyuridine was used to determine the percentage of cells synthesizing DNA (proliferative fraction). When bromodeoxyuridine was administered either in vivo (n = 93) or in vitro (n = 79), p53 accumulation was only marginally related to proliferative fraction (P = 0.067 by chi 2; P = 0.055 by Mann-Whitney). When tumors were segregated by ER status, the aforementioned associations of p53 immunopositivity with PR negativity, high histological grade, and increased proliferation rate lost their significance. p53 accumulation did not correlate with tumor size, clinical stage, axillary node metastases, or age at diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Tumor labeling indices of primary breast cancers and their regional lymph node metastases.

BACKGROUND: Tumor labeling index has emerged as a strong predictor of the clinical course of women with breast cancer. This study investigated whether labeling index of primary tumors correlates with labeling indices of concurrent regional node metastases. METHODS: With appropriate written consent, preoperative in vivo infusion of the thymidine analogue 5-bromodeoxyuridine (BrdUrd) was used to label 109 human breast cancers. Labeled S-phase cells were identified immunohistochemically with an antibody specific to DNA-incorporated BrdUrd. Labeling index was the fraction of labeled nuclei in 2000 tumor nuclei. For 30 women, there was sufficient cancer in axillary lymph nodes to compare labeling indices in primary breast cancer and regional lymph node metastases. RESULTS: The 30 women were from 25 to 82 years of age. Tumors were from 1 to 12 cm in size and there were from 1 to 26 positive nodes. Tumor labeling index ranged from 0.1% to 34%, (mean, 11.1%; median, 10.3%) and axillary lymph node metastasis labeling index ranged from 0.1% to 27.7% (mean, 10.8%; median, 10.0%). There was strong correlation between primary tumor labeling index and regional lymph node metastases labeling index (r = 0.82, with 95% confidence interval 0.65-0.91). The correlation persisted within subgroups according to age, tumor size, number of positive nodes, and hormone receptor status. Primary tumor and lymph node metastases labeling indices also had statistically similar relationships with age, level of hormone receptors, tumor size, and number of positive nodes. CONCLUSIONS: Primary tumor and regional node labeling indices correlate strongly; the relationship is not influenced by age, level of hormone receptors, tumor size, or number of positive nodes.

Adult↗
PubMed1993

Molecular aspects of early stages of breast cancer progression.

It is clear that breast cancer progression is associated with inactivation of a number of different recessive oncogenes. The most widely evaluated tumor suppressor gene, p53, is mutated in approximately 30-50% of sporadic breast cancers. Mutations usually occur early in malignant progression. Loss of heterozygosity (LOH) studies have identified numerous chromosomal regions where other recessive oncogenes relevant to breast cancer may be located. Each LOH is seen in a varying proportion of breast cancers and may appear either early or late in progression. High-grade ductal carcinoma in situ (DCIS) and invasive carcinoma have similar genetic lesions, showing that aberrations can occur before invasive disease. Direct evidence that the same aberrations can be acquired later in progression comes from a study of multiple metastases from the same patient; other studies found that primary invasive cancers are characterized by marked intratumor heterogeneity for each lesion examined. The model we propose to account for these results hypothesizes that multiple genetic lesions can accomplish each phenotype required for malignancy (i.e., dysregulated proliferation, invasion, angiogenesis, etc.) and that, for a given tumor, at least one aberrant gene for each phenotypic change is stochastically selected. Biological heterogeneity of breast cancer results from the stochastic acquisition of various genetic aberrations. We further propose that the lymphocytic reaction in high-grade DCIS may select for aggressive tumor subpopulations capable of escaping immune surveillance. Another aspect of tumor heterogeneity may be the multiple mechanisms employed by various tumors to escape immune surveillance.

Breast Neoplasms↗
PubMed1993

Correlation of bromodeoxyuridine (BRDU) labeling of breast carcinoma cells with mitotic figure content and tumor grade.

Tumor proliferation is inversely associated with survival in patients with breast carcinoma. Labeling of tumor cells with bromodeoxyuridine (BRDU) correlates highly with that seen with [3H]thymidine, the current "gold standard" for measuring tumor S-phase. However, the relationship of BRDU labeling to mitotic figure content and tumor grade remains incompletely defined. To determine this, we labeled 55 breast carcinomas with BRDU in vivo and correlated the results with mitotic figure content. The BRDU labeling index was the number of BRDU-positive cells/2,000 tumor cells, the mitotic figure index was the number of mitotic figures per 1,000 tumor cells, and the mitotic figure count was the number of mitotic figures per 10 high-powered fields. BRDU labeling was also correlated with tumor grade (Scarff-Bloom-Richardson). The BRDU labeling index correlated highly with the mitotic figure index (r = 0.814, p = 7.0 x 10(-14)), mitotic figure count (r = 0.725, p = 6.0 x 10(-10)), and tumor grade (r = 0.68, p = 1.1 x 10(-8)). The correlation of BRDU labeling with mitotic figure content was strong enough to suggest that a very carefully measured mitotic figure index provides an estimate of tumor growth fraction equivalent to the BRDU labeling index. Also, analysis of variance showed that the mitotic figure index was twice as precise as the mitotic figure count in estimating BRDU labeling, and thus was a more accurate measure of tumor proliferation. Moreover, measurements made by the mitotic figure index were as precise as those made by BRDU labeling. However, which method is optimal for estimating tumor proliferation rate remains unclear. Further studies are indicated.

Adult↗
PubMed1993

Effects of short-term culture on benign and malignant human breast epithelium analyzed by image analysis.

The ability to culture malignant breast cells is crucial to the success of many scientific studies. However, short-term cultures of breast cancers are composed predominantly of DNA diploid cells, leading to doubt regarding the presence of bonafide cancer cells in these cultures. Morphology by conventional light microscopy is not helpful since cultured benign cells take on features usually associated with malignancy. In this study we examined by image analysis both benign and malignant breast cancer cells before and after culture. Consistent changes in both benign and malignant cells were found following culturing. There also were consistent differences distinguishing the cultures derived from benign and malignant specimens. While the features used were not sufficiently powerful to identify individual cells or cultures as benign or malignant, our results strongly suggest that malignant breast cells do indeed grow in short-term cultures.

Adult↗
PubMed1992

Heterogeneity for allelic loss in human breast cancer.

BACKGROUND: Loss of heterozygosity (LOH) at specific chromosomal regions in the tumor cells implicates the presence of tumor suppressor genes. However, it is also possible for an LOH to be randomly acquired and irrelevant to tumor development. PURPOSE: To determine whether a particular LOH in human breast carcinomas represents a loss of tumor suppressor gene or merely a random loss, we analyzed untreated primary breast cancers for LOH. METHODS: Ninety-eight primary human breast cancers from previously untreated patients were analyzed for LOH at 12 chromosomal regions including five randomly selected regions and seven regions previously reported in other cancer types and/or breast cancers. RESULTS: The baseline incidence of LOH was five out of 124 tests (4%) using randomly selected probes on chromosomes 1p, 2p, 4p, 11q, and Xq. Incidences of LOH significantly greater than background were seen in the following chromosomal regions: 22q (10 of 26 cases, 38%); 18p (five of 24 cases, 21%); 17p (30 of 59 cases, 51%); 13q (five of 14 cases, 36%); 3p (13 of 28 cases, 46%); and 1q (18 of 70 cases, 26%). In contrast to previous reports, the incidence of LOH was not significantly different from background for 11p15. In all cases, results were the same for metastatic lymph nodes and primary tumors, suggesting that the losses occurred early in the malignant progression. In cases with LOH at more than one locus, the same DNA sample often varied in degree of signal reduction for the missing alleles. CONCLUSION: These observations indicate the presence of both intertumor and intratumor heterogeneity for LOH.

Adult↗
PubMed1992

The HER2 (c-erbB-2) oncogene is frequently amplified in in situ carcinomas of the breast.

Amplification and overexpression of the HER2 (c-erbB-2) oncogene was assessed in paraffin-embedded specimens from 27 in situ carcinomas of the breast and from 122 stage II breast cancers. Gene amplification detected in these archival tissues by differential polymerase chain reaction (PCR) was found in 48% of in situ carcinomas and in 21% of stage II lesions (chi 2 = 7.62, p less than or equal to 0.01). In addition, the level of gene amplification correlated with the level of HER2 oncoprotein expression as measured by immunohistochemistry for both in situ cancers (p less than or equal to 0.025) and stage II cancers (p less than or equal to 0.0005). This high incidence of HER2 gene amplification with accompanying overexpression in non-invasive breast tumors suggests that perturbations of the HER2 oncogene are among the earliest and most common genetic lesions in human breast cancer.

Breast Neoplasms↗
PubMed1991

Loss of heterozygosity on the short arm of chromosome 17 is associated with high proliferative capacity and DNA aneuploidy in primary human breast cancer.

Loss of heterozygosity (LOH) on the short arm of chromosome 17 (17p) was found in 27 of 52 (52%) previously untreated primary breast cancers. There was a significant correlation between this 17p allelic loss and two parameters associated with aggressive tumor behavior: high cellular proliferative fraction and DNA aneuploidy. These correlations with high cellular proliferative fraction and DNA aneuploidy were not found in tumors with LOH at nine other chromosome locations. The p53 gene, a putative tumor suppressor gene located at 17p13, was examined for aberrations to determine whether it is the target for the 17p LOH in breast cancer. Unlike other types of human cancer, there were no homozygous deletions or rearrangements of the p53 gene, and only 2 of 13 (15%) were mutated in the conserved region where mutational "hot spots" have been previously located. Therefore, we hypothesize that, in breast cancer, either loss or inactivation of gene(s) on chromosome 17p other than the p53 gene or a different mechanism of p53 gene inactivation may be responsible for the observed high labeling index and DNA aneuploidy associated with LOH at 17p.

Base Sequence↗