Proliferative indices and oncoprotein expression in benign and malignant breast biopsies

Ki-67 expression in sclerosing adenosis and adjacent normal breast terminal ductal lobular units: a nested case-control study from the Mayo Benign Breast Disease Cohort

Sclerosing adenosis (SA) increases risk for invasive breast cancer (BC) 2.1 times relative to that in the general population. Here, we sought to evaluate whether the proliferation marker Ki-67 stratifies risk among women with SA. A nested case-control sample of patients with SA was obtained from the Mayo Clinic Benign Breast Disease Cohort. Ki-67 expression was evaluated in SA lesions and in the adjacent normal terminal duct lobular units (TDLU) in women who did (cases, n = 133) or did not (controls, n = 239) develop BC. Ki-67 was scored by intensity and number of positively stained cells per one high-power field (magnification, ×40) (40× HPF) for both SA and normal TDLU. Associations of Ki-67 expression with case-control status were assessed using conditional logistic regression. Higher Ki-67 expression was significantly associated with case-control status in both SA (P = 0.03) and normal background TDLU (P = 0.006). For the SA lesion, >2 average positively stained cells/40× HPF showed an adjusted odds ratio (OR) of 1.9 (95 % CI, 1.1-3.4) compared to samples with an average of ≤2 positively stained cells. For background TDLU, lobules with >2 but ≤6 average positively stained cells showed an adjusted OR of 1.3-1.5, whereas those with an average of >6 positively stained cells had an OR of 2.4 (95 % CI, 1.1-5.3) compared to those with an average of <2 positively stained cells. Among women with SA, increased Ki-67 expression in either the SA lesion or the normal background TDLU carried an approximately twofold increased odds of subsequent BC as compared to lower Ki-67 expression.

Cancer biomarker HER-2/neu in breast cancer in Indian women

AIM AND OBJECTIVES

In Indian women with breast cancer, the HER-2/neu gene is amplified in 30% of cases. Elevated serum HER-2/neu levels have been shown to be associated with a poor clinical prognosis and decreased survival in early stage breast cancer patients, and testing for this may help to manage the disease. The present study was therefore to estimate serum HER-2/neu levels in breast cancer patients and associate these with other prognostic factors.

MATERIALS AND METHODS

Serum HER-2/neu levels were studied in 207 patients with breast cancer, 15 with benign breast diseases, (BBD) and 175 age-matched healthy controls. Patients' age, menopausal status, node, and estrogen receptor (ER) and progesterone receptor (PgR) status were compared with serum HER-2/neu levels.

RESULTS

Serum HER-2/neu overexpression was associated with age, disease stage and positive nodal status but not with menopausal status. Serum HER-2/neu levels were negatively correlated with hormone receptor positivity.

CONCLUSION

HER-2/neu serum tests should be done more frequently in Indian women with breast cancer, irrespective of their ER and PgR hormone receptor status. ELISA is a reliable and economical tool to assess the HER-2/neu status in tumors, when breast tissue samples are not available.

Differences in Breast Cancer Risk Factors by Tumor Marker Subtypes among Premenopausal Vietnamese and Chinese Women

We evaluated associations between reproductive and lifestyle risk factors with breast cancer tumor marker status in a case-control study. Cases were premenopausal women living in Vietnam and China who were eligible for a clinical trial of oophorectomy and tamoxifen as treatment for breast cancer (n = 682). Controls were nonrelative hospital visitors, matched on age to the cases (n = 649). Immunohistochemical analysis was used to identify the presence of estrogen receptor (ER) and progesterone receptor and the overexpression of HER-2/neu oncogene. Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using unconditional logistic regression, adjusted for known confounders. Overall, 280 (61%) tumor samples were ER positive and 176 (38%) were ER negative. HER-2/neu overexpression was detected in 161 (35%) samples, whereas 286 (26%) samples were HER-2/neu negative. We observed an inverse trend between increasing parity and decreasing breast cancer risk (P = 0.002). Women ages ≥25 years at first birth had increased breast cancer risk compared with women ages &lt;25 years at first birth (OR, 1.53; 95% CI, 1.20-1.95). Women who consumed alcohol had increased risk of breast cancer compared with women who did not (OR,1.85; 95% CI, 1.32-2.61). Compared with controls, OR estimates for breast cancer by parity and age at first birth were significantly associated with ER and/or HER-2/neu tumor status by Wald test (P &lt; 0.05). Family history, age at menarche, cumulative lactation, body mass index, and education were not significantly related to breast cancer risk. Our findings support the hypothesis that some breast cancer risk factors differ by ER and HER-2/neu tumor marker subtypes.

DNA ploidy analyses in 218 consecutive Pakistani breast cancer patients: does it add anything?

An analysis was made to evaluate the significance of DNA ploidy in the biology and prognosis of breast carcinoma. This was done by estimating the correlation of DNA ploidy with other established prognostic markers of breast cancer, namely tumor size, tumor grade, lymph node metastasis and S-phase fraction. From 1995 up to year 2000 ploidy analysis was performed on 218 consecutive cases of infiltrating breast carcinoma by flow cytometry using formalin fixed paraffin embedded material. From the laboratory record, data regarding other pathological variables was retrieved. No correlation could be found between DNA ploidy and tumor grade, nor could there be found a correlation with tumor size. For lymph node metastasis there was a significant difference between the proportion of aneuploids and diploids having metastasis in more than 4 lymph nodes. However, no significant difference was found in axillary lymph node positive and negative groups when number of positive lymph nodes was not taken into account. The mean value of S-phase fraction for the aneuploids and the diploids was also insignificantly different. In conclusion DNA ploidy alone did not add much to predict tumor behaviour in terms of known pathologic variables.

Progression of premalignant MCF10AT generates heterogeneous malignant variants with characteristic histologic types and immunohistochemical markers

The MCF10AT premalignant human breast epithelial cells form benign ductal structures in immunodeficient mice which sporadically progress to carcinoma in situ and invasive cancers of different histologic types. MCF10CA1 cell lines are malignant variants derived by serially passing small pieces of tumors in athymic mice before establishing cells in culture. As these MCF10CA1 variants gave rise to heterogeneous tumors, some cell lines were cloned. Inoculated into immunodeficient mice, these variants produce squamous carcinomas with an undifferentiated component or adenocarcinomas also with an undifferentiated component. Immunohistochemistry utilized antibodies against DF3, c-erbB-2, cyclin Dl, m keratin, p keratin, p53, B72.3 and estrogen receptor. We detected characteristic patterns for squamous carcinomas, for adenocarcinomas, and for each undifferentiated component, that is the undifferentiated components of the squamous and glandular carcinomas were distinct. Only adenocarcinomas were focally ER positive. One uncloned variant that produced cancers with a glandular component, MCF10CA1h, was cloned and cells were injected into mice. This clone produced only undifferentiated carcinomas that, compared to tumors formed by the parental uncloned variant, had lost ER, DF3 and c-erbB-2 expression, but more strongly expressed p53. Our data demonstrate the potential of the premalignant MCF10AT model to generate heterogeneity, including both estrogen receptor-positive as well as estrogen receptor-negative tumors, during progression.

S-phase fraction and breast cancer--a decade of experience

During the past decade, more than 300 articles, abstracts, and book chapters have been published about S-phase fraction (SPF) determined by DNA flow cytometry and its clinical utility for patients with breast cancer. However, the use of SPF for making treatment decisions for breast cancer patients remains controversial. After reviewing 273 published articles, we conclude: 1) Despite different techniques and cutpoints, correlations between SPF and other prognostic markers are relatively consistent across studies; higher SPF is generally associated with worse tumor grade, absence of steroid receptors, larger tumors, and positive axillary lymph nodes. 2) Higher SPF is generally associated with worse disease-free and overall survival in both univariate and multivariate analyses; SPF values from laboratories that have conducted validation studies can be used, in combination with other factors, to estimate the prognosis of patients with primary breast cancer. 3) There is considerable variability among laboratories regarding assay methodology, cell-cycle analysis techniques, and cutpoints for classifying and interpreting SPF; use of SPF values from different laboratories is problematic, and there remains a need for standardization of these processes and well-designed confirmation studies. We conclude that measurement of SPF does have clinical utility for patients with breast cancer, but standardization and quality control must be improved before it can be routinely used in community settings.