Prognostic factors for patients with carcinoma of the breast

p53, cathepsin D, Bcl-2 are joint prognostic indicators of breast cancer metastatic spreading

Background

Traditional prognostic indicators of breast cancer, i.e. lymph node diffusion, tumor size, grading and estrogen receptor expression, are inadequate predictors of metastatic relapse. Thus, additional prognostic parameters appear urgently needed. Individual oncogenic determinants have largely failed in this endeavour. Only a few individual tumor growth drivers, e.g. mutated p53, Her-2, E-cadherin, Trops, did reach some prognostic/predictive power in clinical settings. As multiple factors are required to drive solid tumor progression, clusters of such determinants were expected to become stronger indicators of tumor aggressiveness and malignant progression than individual parameters. To identify such prognostic clusters, we went on to coordinately analyse molecular and histopathological determinants of tumor progression of post-menopausal breast cancers in the framework of a multi-institutional case series/case-control study.

Methods

A multi-institutional series of 217 breast cancer cases was analyzed. Twenty six cases (12 %) showed disease relapse during follow-up. Relapsed cases were matched with a set of control patients by tumor diameter, pathological stage, tumor histotype, age, hormone receptors and grading. Histopathological and molecular determinants of tumor development and aggressiveness were then analyzed in relapsed versus non-relapsed cases. Stepwise analyses and model structure fitness assessments were carried out to identify clusters of molecular alterations with differential impact on metastatic relapse.

Results

p53, Bcl-2 and cathepsin D were shown to be coordinately associated with unique levels of relative risk for disease relapse. As many Ras downstream targets, among them matrix metalloproteases, are synergistically upregulated by mutated p53, whole-exon sequence analyses were performed for TP53, Ki-RAS and Ha-RAS, and findings were correlated with clinical phenotypes. Notably, TP53 insertion/deletion mutations were only detected in relapsed cases. Correspondingly, Ha-RAS missense oncogenic mutations were only found in a subgroup of relapsing tumors.

Conclusions

We have identified clusters of specific molecular alterations that greatly improve prognostic assessment with respect to singularly-analysed indicators. The combined analysis of these multiple tumor-relapse risk factors promises to become a powerful approach to identify patients subgroups with unfavourable disease outcome.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2713-3) contains supplementary material, which is available to authorized users.

A seven-gene CpG-island methylation panel predicts breast cancer progression

Background

DNA methylation regulates gene expression, through the inhibition/activation of gene transcription of methylated/unmethylated genes. Hence, DNA methylation profiling can capture pivotal features of gene expression in cancer tissues from patients at the time of diagnosis. In this work, we analyzed a breast cancer case series, to identify DNA methylation determinants of metastatic versus non-metastatic tumors.

Methods

CpG-island methylation was evaluated on a 56-gene cancer-specific biomarker microarray in metastatic versus non-metastatic breast cancers in a multi-institutional case series of 123 breast cancer patients. Global statistical modeling and unsupervised hierarchical clustering were applied to identify a multi-gene binary classifier with high sensitivity and specificity. Network analysis was utilized to quantify the connectivity of the identified genes.

Results

Seven genes (BRCA1, DAPK1, MSH2, CDKN2A, PGR, PRKCDBP, RANKL) were found informative for prognosis of metastatic diffusion and were used to calculate classifier accuracy versus the entire data-set. Individual-gene performances showed sensitivities of 63–79 %, 53–84 % specificities, positive predictive values of 59–83 % and negative predictive values of 63–80 %. When modelled together, these seven genes reached a sensitivity of 93 %, 100 % specificity, a positive predictive value of 100 % and a negative predictive value of 93 %, with high statistical power. Unsupervised hierarchical clustering independently confirmed these findings, in close agreement with the accuracy measurements. Network analyses indicated tight interrelationship between the identified genes, suggesting this to be a functionally-coordinated module, linked to breast cancer progression.

Conclusions

Our findings identify CpG-island methylation profiles with deep impact on clinical outcome, paving the way for use as novel prognostic assays in clinical settings.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1412-9) contains supplementary material, which is available to authorized users.

Small invasive breast carcinomas in Taiwanese women

BACKGROUND

Female Taiwanese breast cancer patients are younger than their Western counterparts. This study examined the predictors of axillary lymph node metastases in Taiwanese women with T1 breast cancer.

METHODS

Data from 394 Taiwanese women with T1 invasive breast carcinoma were retrospectively reviewed.

RESULTS

The data contained 6 T1a, 51 T1b, and 337 T1c breast tumors. The patients' ages ranged from 23 to 82 years (mean +/- SD, 48.2 +/- 11.4 years; median, 46.4 years). Axillary nodal metastases were present in 38.3% of the patients (16.7% in T1a, 35.3% in T1b, and 39.2% in T1c tumors). The patients with nodal metastases had significantly greater body weights and S-phase fractions than those without nodal metastases. Univariate analysis revealed that unfavorable pathology, lymphovascular invasion, S-phase fraction >7%, and nondiploid DNA ploidy were significantly associated with lymph node metastases. Lymphovascular invasion was the only significant variable as the independent predictor in the multiple logistic regression analysis. In the Cox proportional hazards regression analysis, axillary nodal status and lymphovascular invasion were significantly associated with survival.

CONCLUSIONS

Taiwanese women with small breast cancer displayed a relatively higher incidence of axillary lymph node metastases than Western women. Axillary lymph node dissection or sentinel lymph node biopsy should be conducted on Taiwanese patients with small invasive breast carcinomas, particularly when risk factors exist.

Predictors of lymph node metastasis in T1 breast carcinoma, stratified by patient age

It is important to identify T1-substage breast carcinomas (BCs) which are inherently aggressive, so that these can be managed more assertively. The purpose of this study was to distinguish those T1 BCs with the potential to metastasize to axillary lymph nodes from those lacking that ability by multiparametric analysis of several clinicopathologic features. The authors studied 197 patients with invasive BC who had undergone modified radical mastectomy; 161 tumors were ductal and 26 were lobular BCs. The study group was stratified by age into two groups: </=34 years (n = 34) and 35-84 years (n = 153). Pathologic lymph node status was correlated with estrogen receptor (ER) and progesterone receptor (PR) tumor positivity, MIB-1 proliferation index, and immunoreactivity for mutant p53 protein. These factors were studied immunohistologically using standard methodology and microwave-mediated epitope retrieval. Statistical analyses employed accepted techniques. Women in this study ranged from 22 to 84 years of age; 39 (21%) had positive lymph nodes. ER-positive tumors comprised 73% of the total; similarly, 65% were PR positive. The MIB-1 index was greater than 10% in 44% of lesions, and 14% demonstrated labeling for mutant p53 protein. Using crude odds ratio data, the MIB-1 index was the only indicator found to predict lymph node metastasis significantly (p < 0.001). Moreover, even when adjustments were made for patient age, logistic regression analysis confirmed the utility of MIB-1-values of greater than 10% in this context, with a 4.4 greater likelihood of metastasis (p < 0.001). MIB-1 indices of greater than 10% are associated with a risk of lymph node metastasis from T1 BCs, independent of patient age. Hormone receptor status and immunohistologic p53 status are not predictors of nodal involvement in this specific setting.

Molecular markers in male breast carcinoma

BACKGROUND

In contrast to female breast carcinoma, information regarding the prevalence and prognostic information of new molecular markers is limited in male breast carcinoma. The objective of this study was to assess the degree of expression and prognostic value of estrogen receptors (ER), progesterone receptors (PR), androgen receptors (AR), bcl-2, p53, HER-2/neu, cyclin D1, and MIB-1 in a cohort of male breast carcinoma patients.

METHODS

A computerized search of the medical index, tumor registry, and tissue registry was used to identify 111 male patients with a diagnosis of primary adenocarcinoma of the breast seen between 1950-1992 at the Mayo Clinic. Of these, 77 patients had adequate tissue specimens available for the immunohistochemical analysis of the markers. Immunoperoxidase staining was performed by an automated avidin-biotin complex method. Progression free (PFS) and overall (OS) survival distributions were estimated using the Kaplan-Meier method. The log rank test was used to determine whether any patient characteristic, tumor feature, or molecular marker was associated significantly with PFS or OS.

RESULTS

The majority of tumor specimens were positive for ER (91%), PR (96%), AR (95%), and bcl-2 (94%). Fewer positive specimens were found for cyclin D1 (58%), MIB-1 (38%), HER-2/neu (29%), and p53 (21%). The 5-year PFS and 10-year OS for the entire patient cohort was estimated to be 66% (95% confidence interval [CI], 57-77%) and 38% (95% CI, 29-50%), respectively. PFS was decreased significantly for those patients with tumors staining positively for MIB-1 (P=0.012) or negatively for cyclin D1 (P=0.009). OS was not found to differ significantly with respect to these markers.

CONCLUSIONS

The nearly universal expression of hormone receptors in these tumors suggests a central role for endogenous hormones in male breast carcinoma. The high degree of AR expression would suggest that antiandrogen therapy should be explored further. The high frequency of bcl-2 positivity may implicate antiapoptotic mechanisms in the carcinogenesis of male breast carcinoma. The finding of decreased PFS in MIB-1 positive tumors supports the role of proliferative activity as a negative prognostic factor in male breast carcinoma. Positive cyclin D1 expression is associated with increased PFS in male breast carcinoma patients, which suggests that interactions among cell cycle regulatory proteins may be important in this disease.

A laboratorian’s perspective on evaluation and implementation of new laboratory tests

New assay development should be directed toward answering fundamental clinical questions. Caveats that must be considered before initiating assay development projects are: New assays should allow the clinician to interact with and treat a patient more effectively, thereby improving medical outcome; and new assays should facilitate recapture of system resources, enabling cost savings or reinvestment of resources. Defining the clinical questions and consideration of the caveats permit a means of prioritizing assay development activities. Laboratorians are faced with evaluating several types of development activities that lead to assay implementation in routine clinical testing. Assays can be prioritized for up-grading to newer cost-effective technologies, provided the changes maintain or improve analytical and clinical performance. Predicting which research assay will have future value is difficult when clinical performance is not fully validated. However, such assay development has the greatest potential for changing the delivery of healthcare by a clinician.

Flow cytometric DNA hypertetraploidy is associated with unfavourable prognostic features in breast cancer

AIM

Breast tumours with a DNA content higher than 4N (hypertetraploidy) are not well characterised. The aim of this study was to evaluate the clinical and biological characteristics of 51 hypertetraploid breast carcinomas selected from a series of 860 consecutive cases analysed by flow cytometry.

METHODS

The clinicopathological characteristics of the hypertetraploid group were compared with those of a control group of 138 non-hypertetraploid breast carcinomas. Breast tumours from patients submitted to surgery as primary therapeutic approach (15 hypertetraploid and the 138 non-hypertetraploid) were TNM staged and classified according to the histological type and grade. The remaining 36 patients had advanced neoplastic disease at presentation and were classified by cytological criteria only. DNA flow cytometric analysis was performed on fresh-frozen samples stained with propidium iodide. Hormone receptors were analysed by immunocytochemistry.

RESULTS

The incidence of hypertetraploid breast tumours was 5.9% (51 of 860). All the patients were women and the mean age at diagnosis was 65 years. There was a family history of breast cancer in 21.6% of cases. In the group of operated patients, 33.3% had pT3 tumours and 53.3% had axillary lymph node metastases. All but one tumour were invasive ductal carcinomas; the remaining was an invasive papillary carcinoma. Ten (66.7%) tumours were classified as poorly differentiated carcinomas. Oestrogen and progesterone receptors were negative in 33 (64.7%) and 38 (74.5%) tumours, respectively. At last follow up, 35 (72.9%) patients were alive, while 13 (27.1%) died of disease within three years of diagnosis. Statistical comparison of the clinicopathological features of hypertetraploid v non-hypertetraploid breast carcinomas yielded a significant difference in tumour size (p < 0.001), histological grade (p < 0.001), hormone receptor status (p < 0.001), and overall survival (p < 0.001) between the two groups.

CONCLUSION

Flow cytometric DNA hypertetraploidy is related to clinicopathological features of breast cancer usually associated with unfavourable prognosis.