Hormonal Factors and Breast Tumor Proliferation: Do Factors that Affect Cancer Risk also Affect Tumor Growth?

Age groups related glioblastoma study based on radiomics approach

Glioblastoma is the most aggressive malignant brain tumor with poor prognosis. Radiomics is a newly emerging and promising technique to reveal the complex relationships between high-throughput medical image features and deep information of disease including pathology, biomarkers and genomics. An approach was developed to investigate the internal relationship between magnetic resonance imaging (MRI) features and the age-related origins of glioblastomas based on a quantitative radiomics method. A fully automatic image segmentation method was applied to segment the tumor regions from three dimensional MRI images. 555 features were then extracted from the image data. By analyzing large numbers of quantitative image features, some predictive and prognostic information could be obtained by the radiomics approach. 96 patients diagnosed with glioblastoma pathologically have been divided into two age groups (<45 and ≥45 years old). As expected, there are 101 features showing the consistency with the age groups (T test, p < .05), and unsupervised clustering results of those features also show coherence with the age difference (T test, p= .006). In conclusion, glioblastoma in different age groups present different radiomics-feature patterns with statistical significance, which indicates that glioblastoma in different age groups should have different pathologic, protein, or genic origins.

Her2 negative luminal breast carcinoma and Ki-67 evaluation

AIM

To determine the degree of inter-observer variability in defining the percentage of Ki-67 immunohistochemical expression in breast carcinoma cases and to investigate the validity of using the cut-point of 14% for the administration of adjuvant treatment in luminal B (Her2 negative) carcinomas.

MATERIALS AND METHODS

99 ER, PR positive, Her2 negative breast carcinomas were consecutively selected from the Pathology files of "IASO" Women's Hospital. Ki-67 immunostaining was evaluated by four pathologists from four different institutions.

RESULTS

Concerning the whole study group, the inter-observer agreement was substantial. Subgroup analysis upon the cases were at least one observer evaluated Ki-67 as being less than 14% showed that the inter-observer agreement was reduced to fair. Further analysis revealed that both below and above the clinicopathological limit of 14%, stands a "grey zone" of about ±7%, in which inter-observer agreement is weak.

CONCLUSION

The administration of cytotoxic therapy in ER, PR positive, Her2 negative breast carcinomas featuring a Ki-67 labeling index of around 14, should be considered with caution. Probably decision-making should also take under consideration the whole morphological and biological profile of each tumor.

The influence of menstrual risk factors on tumor characteristics and survival in postmenopausal breast cancer

Introduction

Hormonal factors are implicated in tumor progression and it is possible that factors influencing breast cancer induction could affect prognosis. Our study investigated the effects of menstrual risk factors on tumor characteristics and survival in postmenopausal breast cancer.

Methods

We used a nationwide, population-based, case-case design of 2,640 Swedish women who were 50 to 74 years old and had postmenopausal breast cancer during 1993 to 1995. Follow-up was conducted until 31 December 2000. We used polytomous multiple logistic regression to investigate the relationships between menstrual factors (age at menarche, cycle length, irregular menstruation, lifetime number of menstrual cycles, and age at menopause), tumor characteristics (size, grade, estrogen receptor and progesterone receptor [PR] status, lymph node involvement, and histology), and Cox proportional hazards modeling for 5-year survival.

Results

Younger ages at menarche were significantly associated with grade and lymph node involvement. Women with an age at menarche of 11 years or younger had a more than twofold excess risk of medium-grade (odds ratio [OR] = 2.05; 95% confidence interval [CI] 1.00 to 4.18) and high-grade (OR = 2.04; 95% CI 1.01 to 4.16) tumors. Early menarche significantly increased the risk of lymph node metastases. Survival was poorest in women with the earliest age at menarche, with a 72% increased risk of dying within 5 years after diagnosis (hazard ratio = 1.72; 95% CI 1.02 to 2.89). No significant associations were observed for other menstrual factors with tumor characteristics or survival.

Conclusions

Age at menarche has a significant impact on breast cancer prognosis and survival. It remains to be established whether the associations are attributable to age at menarche directly or are associated with the early-life physiological events of breast development and carcinogenesis also taking place during childhood and puberty, as menarche is only the culmination of this series of events.

Proliferation marker securin identifies favourable outcome in invasive ductal breast cancer

We introduce a new proliferation marker, securin (pituitary tumour-transforming 1 (PTTG1)), analysed in invasive ductal breast carcinomas by cDNA microarrays and immunohistochemistry. In cDNA microarray of a total of 4000 probes of genes, securin was revealed with a significant change in expression among the several proliferation-related genes studied. The value of securin as a proliferation marker was verified immunohistochemically (n=44) in invasive ductal breast cancer. In follow-up analyses of the sample of patients, the prognostic value of securin was compared with the established markers of breast cancer proliferation, Ki-67 and mitotic activity index (MAI). Our results of a small sample of patients suggest that low securin expression identifies a distinct subgroup of more favourable outcome among patients with high Ki-67 immunoexpression or high MAI. In univariate analysis of Cox's regression, 10-unit increment of securin immunopositivity was associated with a 2.3-fold overall risk of death due to breast cancer and a 7.1-fold risk of death due to breast cancer in the sample of patients stratified according to the cutoff points of 10 and 20% of securin immunopositivity. We suggest that securin immunostaining is a promising and clinically applicable proliferation marker. The finding urges further prognostic studies with a large sample of patients.

Prediagnostic use of hormone therapy and mortality after breast cancer

BACKGROUND

A few studies have observed reduced breast cancer mortality in women who used hormone therapy before diagnosis. Due to the high prevalence of past and current hormone use, it is important to investigate whether these preparations are related to breast cancer mortality.

METHODS

To evaluate the influence of prediagnostic use of hormone therapy on breast cancer mortality, a prospective cohort of 12,269 women ages 50 years or more diagnosed with incident invasive breast cancer and residents of Wisconsin, Massachusetts, or New Hampshire were enrolled in three phases beginning in 1988. They were followed for death until December 31, 2005, using the National Death Index. Cumulative mortality and multivariable adjusted hazard rate ratios for breast cancer and other mortality causes were calculated for women according to any hormone therapy use, and for exclusive use of estrogen or estrogen-progestin (EP).

RESULTS

During an average 10.3 years of follow-up, 1,690 deaths from breast cancer were documented. Cumulative mortality from breast cancer was lower among hormone therapy users, specifically current users at the time of diagnosis, and EP users, compared with nonusers. Adjusted survival varied by type and duration of hormone therapy before diagnosis. A reduced risk of death from breast cancer was associated with EP preparations (hazard rate ratio, 0.73; 0.59-0.91) and with > or =5 years of EP use (0.60; 0.43-0.84). No association was observed for women who were former or current users of E-alone preparations.

CONCLUSIONS

Although use of combined EP preparations increases breast cancer risk, in this study, use of these hormones before diagnosis was associated with reduced risk of death after a breast cancer diagnosis. The better survival among users, particularly of EP, persisted after adjustment of screening, stage, and measured confounders.

Urine telomerase activity for the detection of bladder cancer in females

PURPOSE

Previous studies have shown that telomerase activity in bladder washings and voided urine represents an important noninvasive tool for bladder cancer diagnosis. With the present case-control study conducted on 212 women, including 144 healthy individuals and 68 patients, at first diagnosis of bladder cancer we confirmed previously obtained diagnostic results and improved the accuracy of this diagnostic assay.

MATERIALS AND METHODS

Telomerase activity was evaluated by quantitative telomeric repeat amplification protocol assay and expressed as arbitrary enzymatic units.

RESULTS

At the best overall cutoff of 50 arbitrary enzymatic units sensitivity was 87% and specificity was 66%. A breakdown analysis as a function of age showed a higher assay accuracy in women younger than 75 years (sensitivity 91% and specificity 69%) compared to older women (sensitivity 64% and specificity 59%).

CONCLUSIONS

Other reasons in addition to age may account for the lower specificity in women with respect to men. In particular, a high number of telomerase positive nonurothelial cells in urine from females could be responsible for false-positive telomeric repeat amplification protocol results. Urine telomerase activity detected by telomeric repeat amplification protocol appears to be a good diagnostic tool in females although it is more accurate in younger than in older women.

Association between reproductive factors and breast cancer survival in younger women

This analysis investigated whether reproductive factors such as age at menarche, parity, and timing and outcomes of pregnancies were associated with survival among women with breast cancer younger than 55 years. Female residents of Atlanta, Georgia, and central New Jersey who were diagnosed with a primary, incident invasive breast cancer between 1990 and 1992 and enrolled in a population-based study (n = 1,264) were followed for 8-10 years. Detailed exposure and covariate information was collected via in-person interviews administered shortly after diagnosis. Vital status as of January 1, 2000 was ascertained through the National Death Index via the state cancer registries (n = 292 deaths). Cox regression methods were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) adjusted for confounders. Parity of 4 or more births, as compared with nulliparity, was positively associated with all-cause mortality, [HR (95% CI) = 1.71 (1.09-2.67)]. Increased mortality was associated with having given birth within 5 years prior to diagnosis (<or=5 vs. >5 years) [1.78 (1.28-2.47)], and was more pronounced among women with a pre-diagnostic body mass index of <25 kg/m2 [2.54 (1.61-4.00)]. Early age at menarche and early age at first birth also modestly increased mortality; history of miscarriage, induced abortion, and ever breastfeeding were not related to survival. These results may help elucidate breast cancer progression mechanisms and enable a better understanding of how reproductive characteristics influence breast cancer survival.

Ki67 immunohistochemistry: a valuable marker in prognostication but with a risk of misclassification: proliferation subgroups formed based on Ki67 immunoreactivity and standardized mitotic index

AIMS

Counting mitotic figures is considered to be a reliable prognosticator, but evaluation of Ki67 immunohistochemistry has become more popular in evaluating proliferation. Our previous studies suggested an occasional discrepancy between mitotic figures and Ki67 fraction. The aim of this study was to investigate this more closely and also to study the associations between bcl-2 and p53 expression and proliferation.

METHODS AND RESULTS

Two hundred and sixty-five infiltrating breast carcinomas were immunostained for Ki67, p53 and bcl-2. The standardized mitotic index (SMI) was determined. Four proliferation groups were based on Ki67 positivity fraction and SMI at optimal cut-off points. Cox's multivariate model was used to test the power of the prognosticators. SMI and nodal status were the most powerful individual prognosticators. Ki67 was an independent prognosticator if nodal status, tumour size, age and histological grade were included in the analysis but not if analysed with SMI. The group with low SMI and low Ki67 fraction had the best prognosis. Groups with high SMI had the poorest prognosis. The group with low SMI and high Ki67 fraction had a favourable prognosis. Bcl-2 negativity and p53 positivity correlated with proliferation.

CONCLUSIONS

We have found a 'wrong positive' Ki67 group with favourable prognosis. SMI cannot be replaced by Ki67 because of the danger of misclassification of some patients.

Association between mammographic breast density and breast cancer tumor characteristics

OBJECTIVE

Few studies have examined the association between breast density and breast cancer tumor characteristics. We examined the association between hormonal, proliferative, and histologic tumor characteristics and mammographic breast density in women with breast cancer.

METHODS

We conducted a cross-sectional analysis in 546 women diagnosed with invasive breast cancer to evaluate the associations between breast density and tumor size, lymph node status, lymphatic or vascular invasion, histologic grade, nuclear grade, tumor differentiation, mitotic index, tumor necrosis, Ki-67 proliferation, estrogen receptor, progesterone receptor, p53, p27, cyclin E, Bcl-2, and C-erb-B2 invasion. Breast density was classified as fatty (Breast Imaging Reporting and Data System code 1 or 2; n = 373) or dense (Breast Imaging Reporting and Data System code 3 or 4; n = 173) for the cancer-free breast. A single pathologist measured all tumor markers. We examined whether the relationships were modified by interval cancer or screen-detected cancer.

RESULTS

Women with a tumor size >1.0 cm were more likely to have dense breasts compared with women with a tumor size < or =1.0 cm after adjusting for confounders (odds ratio, 2.0; 95% confidence interval, 1.2-3.4 for tumor sizes 1.1-2.0 cm; odds ratio, 2.3; 95% confidence interval, 1.3-4.4 for tumor sizes 2.1-10 cm). Tumor size, lymph node status, and lymphatic or vascular invasion were positively associated with breast density among screen-detected cancers. Histologic grade and mitotic index were negatively associated with breast density in women diagnosed with an interval cancer.

CONCLUSIONS

These results suggest that breast density is related to tumor size, lymph node status, and lymphatic or vascular invasion in screen-detected cancers. Additional studies are needed to address whether these associations are due to density masking the detection of some tumors, a biological relationship, or both.

Biennial Versus Annual Mammography and the Risk of Late-Stage Breast Cancer

BACKGROUND

Mammography screening may reduce breast cancer mortality by detecting cancers at an earlier stage. However, certain questions remain, including the ideal interval between mammograms.

METHODS

We conducted an observational study using information collected by seven mammography registries across the United States to investigate whether women diagnosed with breast cancer after having screening mammograms separated by a 2-year interval (n = 2440) are more likely to be diagnosed with late-stage disease (positive lymph nodes or metastases) than women diagnosed with breast cancer after having screening mammograms separated by a 1-year interval (n = 5400). Analyses were stratified by age and breast density to clarify whether groups that have the poorest mammography sensitivity (i.e., women under age 50 years and those with mammographically dense breasts) would benefit most from annual screening. The subjects were women diagnosed with breast cancer between 1996 and 2001 who were 40-89 years old at their index mammographic examination (i.e., the most recent screen at or before breast cancer diagnosis). Data were analyzed by logistic regression, adjusting for race, ethnicity, family history of breast cancer, and mammography registry.

RESULTS

Among women age 40-49 years at the index mammogram, those with a 2-year screening interval were more likely to have late-stage disease at diagnosis than those with a 1-year screening interval (28% versus 21%; odds ratio [OR] = 1.35, 95% confidence interval [CI] = 1.01 to 1.81). There was no increase in late-stage disease for women 50 years or older with a 2-year versus a 1-year screening interval (women age 50-59 years at index mammogram: OR = 0.97, 95% CI = 0.75 to 1.25; women age 60-69 years at index mammogram: OR = 0.99, 95% CI = 0.72 to 1.35; women age 70 years or older at index mammogram: OR = 0.88, 95% CI = 0.64 to 1.19). There was no indication that women with dense breasts would benefit more from a 1-year versus 2-year screening interval than women with fatty breasts.

CONCLUSION

These findings may be useful for policy decisions about appropriate screening intervals and for use in statistical models that estimate the costs and benefits of mammography by age and screening interval.

Factors Contributing to Mammography Failure in Women Aged 40-49 Years

BACKGROUND

Younger women (40-49 years) have lower mammographic sensitivity (i.e., greater proportion of cancers detected after a negative mammogram) than older women (> or =50 years). We explored the effect of tumor growth rate, breast density, mammographic image quality, and breast cancer risk factors on mammographic sensitivity in younger and older women.

METHODS

We studied 576 women (n = 73 aged 40-49 years and n = 503 aged 50 years or older) who were diagnosed with invasive breast cancer between 1988 and 1993. Interval cancers were defined as those diagnosed within 12 or 24 months after a negative screening mammogram and before a subsequent mammogram. Tumor growth rate was assessed by mitotic figure count and Ki-67 positivity. The main outcome measures were percentage of women with interval cancer (1 -mammographic sensitivity) by age, odds ratio (OR) of interval cancer by age, and excess odds (i.e., the percentage of the odds ratio for age that was explained by individual covariates).

RESULTS

Interval cancers occurred in 27.7% of younger women and 13.9% of older women within 12 months (OR = 2.36, 95% confidence interval [CI] = 1.14 to 4.77) and in 52.1% of younger women and 24.7% of older women within 24 months (OR = 3.58, 95% CI = 2.15 to 5.97). Greater breast density explained 67.6% of the decreased mammographic sensitivity in younger women at 12 months, whereas rapid tumor growth explained 30.6% and breast density explained 37.6% of the decreased sensitivity in younger women at 24 months.

CONCLUSIONS

Breast density largely explained decreased mammographic sensitivity at 12 months, whereas rapid tumor growth contributed to decreased mammographic sensitivity at 24 months. A 12-month versus a 24-month mammography screening interval may therefore reduce the adverse impact of faster growing tumors on mammographic sensitivity in younger women.