Comments on the St. Gallen Consensus 2003 on the Primary Therapy of Early Breast Cancer

Can Estrogen Receptor, Progesterone Receptor, and Proliferative Index be Considered as Isolated Prognostic Factors of Overall Survival in Early luminal Breast Cancer?

BACKGROUND: There are a number of proven molecular and pathological markers important for the prognosis for OS of early luminal type breast cancer, but there are still some deficiencies mainly due to the non-linear relationship between the markers and the outcome of the disease. METHODS AND PATIENTS: In this retro-prospective study, clinical and pathological data were provided from 336 patients with breast cancer who underwent breast surgery and treatment between January 2010 and December 2013, and followed until December 2018. The aim of the study was an evaluation of ER, PR, and Ki-67 as independent prognostic factors for OS of early luminal breast cancer. RESULTS: Early luminal breast cancers were not predictive of ER expression status (p = 0.699, p = 0.356), whereas only early Luminal B was predictive for PR expression (>10%: 72.2%). Ki-67 in most of the cases of early Luminal B was with expression of >14–20% (p = 0.056). Patients with ER of 1–10% survived over 80 months (p = 0.0020) in early Luminal A, but ER expression status did not show prognostic significance for OS of early Luminal B (p = 0.775). PR status did not show prognostic significance for OS in early luminal types (p = 0.257, p = 0.622). ER >1%/PR >1% was protective in early Luminal B (p = 0.00043), but not in early Luminal A. CONCLUSION: Our results suggest ER, but not PR as independent prognostic factor for OS but only of early Luminal A. We did not prove Ki-67 as independent prognostic factor for OS of highly proliferative early breast cancer.

Circulating Tumor Cells in HER-2 Positive Metastatic Breast Cancer Patients Treated with Trastuzumab and Chemotherapy

The detection of circulating tumor cells (CTCs) in peripheral blood may have important prognostic and predictive implications in breast cancer treatment. A limitation in this field has been the lack of a validated method of accurately measuring CTCs. While sensitivity has improved using RT-PCR, specificity remains a major challenge. The goal of this paper is to present a sensitive and specific methodology of detecting CTCs in women with HER-2-positive metastatic breast cancer, and to examine its role as a marker that tracks disease response during treatment with trastuzumab-containing regimens.

The study included patients with HER-2-positive metastatic breast cancer enrolled on two different clinical protocols using a trastuzumab-containing regimen. Serial CTCs were measured at planned time points and clinical correlations were made. Immunomagnetic selection of circulating epithelial cells was used to address the specificity of tumor cell detection using cytokeratin 19 (CK19). In addition, the extracellular domain of the HER-2 protein (HER-2/ECD) was measured to determine if CTCs detected by CK19 accurately reflect tumor burden.

The presence of CTCs at first restaging was associated with disease progression. We observed an association between CK19 and HER-2/ECD. The association of HER-2/ECD with clinical response followed a similar pattern to that seen with CK19. Finally, the absence of HER-2/ECD at best overall response and a change of HER-2/ECD from positive at baseline to negative at best overall response was associated with favorable treatment response.

Our study supports the prognostic and predictive role of the detection of CTCs in treatment of HER-2-positive metastatic breast cancer patients. The association between CK19 and markers of disease burden is in line with the concept that CTCs may be a reliable measure of tumor cells in the peripheral blood of patients with metastatic breast cancer. The association of CTCs at first restaging with treatment failure indicates that CTCs may have a role as surrogate markers to monitor treatment response.

Advancement of mass spectrometry-based proteomics technologies to explore triple negative breast cancer

Understanding the complexity of cancer biology requires extensive information about the cancer proteome over the course of the disease. The recent advances in mass spectrometry-based proteomics technologies have led to the accumulation of an incredible amount of such proteomic information. This information allows us to identify protein signatures or protein biomarkers, which can be used to improve cancer diagnosis, prognosis and treatment. For example, mass spectrometry-based proteomics has been used in breast cancer research for over two decades to elucidate protein function. Breast cancer is a heterogeneous group of diseases with distinct molecular features that are reflected in tumour characteristics and clinical outcomes. Compared with all other subtypes of breast cancer, triple-negative breast cancer is perhaps the most distinct in nature and heterogeneity. In this review, we provide an introductory overview of the application of advanced proteomic technologies to triple-negative breast cancer research.

What does breast cancer treatment cost and what is it worth?

The costs of breast cancer care are substantial and growing, and they extend across the spectrum of care. Medical therapies and hospitalizations account for a significant proportion of these costs. Cost-effectiveness analysis (CEA) is the preferred method for assessing the health benefits of medical interventions relative to their costs. Although many CEAs have been conducted for a wide range of breast cancer treatments, these analyses are not used routinely to guide coverage or utilization decisions in the United States. Currently, patients and providers may not consider costs when making most treatment decisions; this is likely to change as payment reform spreads.

A dynamic clinical pathway for the treatment of patients with early breast cancer is a tool for better cancer care: implementation and prospective analysis between 2002-2010

Background

Due to increasing the complexity of breast cancer treatment it is of paramount importance to develop structured care in order to avoid a chaotic and non-consistent management of patients. Clinical pathways, a result of the adaptation of the documents used in industrial quality management namely the Standard Operating Procedures, can be used to improve efficiency and quality of care. They also aim to re-centre the focus on the patient’s overall journey, rather than the contribution of each specialty or caring function independently.

Methods

The effect of the implementation and prospective systematic evaluation of a clinical care pathway for the management of patients with early breast cancer in a single breast unit is evaluated over a long time interval (between 2002 and 2010). Annual analysis of predefined clinical outcome measures, service indicators, team indicators, process indicators and financial indicators was performed. Pathway quality control meetings were organized at least once a year. Systematic feedback was given to the team members, and if necessary the pathway was adapted according to evidence based literature data and in house pathway related data in order to improve quality.

Results

The annual number of patients included in the pathway (289 vs. 390, P <0.01), proportion of patients with Tis-T1 tumors (42% vs. 58%, P <0.01), negative lymph nodes (44% vs. 58%, P <0.01) and no metastases at diagnosis (91.5% vs. 95.9%) has risen significantly between 2002 and 2010. Evolution of mandatory quality indicators defined by EUSOMA shows a significant improvement of quality of cancer care. Particularly, the proportion of patients having anti-hormonal therapy (84.8% vs. 97.4%, P = 0.002) and adjuvant chemotherapy according to the guidelines (72% vs. 95.6%, P = 0.028) increased dramatically. Patient satisfaction improved significantly (P <0.05). Progression free 4-year survival was significantly higher for all patients, for T1 tumors only and for T2-T4 tumors only, treated between 2006 to 2008 compared to between 1999 to 2002 and 2003 to 2005 (P = 0.006, P = 0.05, P = 0.06, respectively). Overall 4-year survival of the entire population treated between 2006 and 2008 was significantly better (P = 0.05).

Conclusions

Although the patient characteristics changed over the years due to better screening, this clinical pathway and regular audit of quality indicators for the treatment of patients with operable breast cancer proved to be important tools to improve the quality of care, patient satisfaction and outcome.

Validation of 70-gene prognosis signature in node-negative breast cancer

PURPOSE

The 70-gene prognosis signature (van't Veer et al., Nature 415(6871):530-536, 2002) may improve the selection of lymph node-negative breast cancer patients for adjuvant systemic therapy. Optimal validation of prognostic classifiers is of great importance and we therefore wished to evaluate the prognostic value of the 70-gene prognosis signature in a series of relatively recently diagnosed lymph node negative breast cancer patients.

METHODS

We evaluated the 70-gene prognosis signature in an independent representative series of patients with invasive breast cancer (N = 123; <55 years; pT1-2N0; diagnosed between 1996 and 1999; median follow-up 5.8 years) by classifying these patients as having a good or poor prognosis signature. In addition, we updated the follow-up of the node-negative patients of the previously published validation-series (Van de Vijver et al., N Engl J Med 347(25):1999-2009, 2002; N = 151; median follow-up 10.2 years). The prognostic value of the 70-gene prognosis signature was compared with that of four commonly used clinicopathological risk indexes. The endpoints were distant metastasis (as first event) free percentage (DMFP) and overall survival (OS).

RESULTS

The 5-year OS was 82 +/- 5% in poor (48%) and 97 +/- 2% in good prognosis signature (52%) patients (HR 3.4; 95% CI 1.2-9.6; P = 0.021). The 5-years DMFP was 78 +/- 6% in poor and 98 +/- 2% in good prognosis signature patients (HR 5.7; 95% CI 1.6-20; P = 0.007). In the updated series (N = 151; 60% poor vs. 40% good), the 10-year OS was 51 +/- 5% and 94 +/- 3% (HR 10.7; 95% CI 3.9-30; P < 0.01), respectively. The DMFP was 50 +/- 6% in poor and 86 +/- 5% in good prognosis signature patients (HR 5.5; 95% CI 2.5-12; P < 0.01). In multivariate analysis, the prognosis signature was a strong independent prognostic factor in both series, outperforming the clinicopathological risk indexes.

CONCLUSION

The 70-gene prognosis signature is also an independent prognostic factor in node-negative breast cancer patients for women diagnosed in recent years.

Selecting high priority quality measures for breast cancer quality improvement

BACKGROUND

Although many quality measures have been created, there is no consensus regarding which are the most important. We sought to develop a simple, explicit strategy for prioritizing breast cancer quality measures based on their potential to highlight areas where quality improvement efforts could most impact a population.

METHODS

Using performance data for 9019 breast cancer patients treated at 10 National Comprehensive Cancer Network institutions, we assessed concordance relative to 30 reliable, valid breast cancer process-based treatment measures. We identified 4 attributes that indicated there was room for improvement and characterized the extent of burden imposed by failing to follow each measure: number of nonconcordant patients, concordance across all institutions, highest concordance at any 1 institution, and magnitude of benefit associated with concordant care. For each measure, we used data from the concordance analyses to derive the first 3 attributes and surveyed expert breast cancer physicians to estimate the fourth. A simple algorithm incorporated these attributes and produced a final score for each measure; these scores were used to rank the measures.

RESULTS

We successfully prioritized quality measures using explicit, objective methods and actual performance data. The number of nonconcordant patients had the greatest influence on the rankings. The highest-ranking measures recommended chemotherapy and hormone therapy for hormone-receptor positive tumors and radiation therapy after breast-conserving surgery.

CONCLUSIONS

This simple, explicit approach is a significant departure from methods used previously, and effectively identifies breast cancer quality measures that have broad clinical relevance. Systematically prioritizing quality measures could increase the efficiency and efficacy of quality improvement efforts and substantially improve outcomes.

The CYP19 TTTA repeat polymorphism is related to the prognosis of premenopausal stage I-II and operable stage III breast cancers

PURPOSE

Given the critical role of the CYP19 gene, encoding aromatase, in estrogen synthesis and the association of the estrogen level with its TTTA repeat polymorphism, the potential influence of this polymorphism on breast cancer survival, and hence management, deserves further study.

METHODS

Genotyping for the CYP19 TTTA repeat polymorphism was performed on 482 stage I-II and operable stage III Taiwanese breast cancer patients. Patients with more than seven TTTA repeats in either allele of CYP19 were defined as having the long allele. We correlated clinical variables and CYP19 genotypic polymorphism with outcome.

RESULTS

In hormone receptor (HR)-positive breast cancers, premenopausal patients with the long allele of the CYP19 polymorphism had a significantly higher overall survival (OS) rate (8-year, 89% versus 68%; p= .003) than those without it. This difference was further demonstrated by a multivariate analysis (OS hazard ratio, 1.53; p= .041). In postmenopausal women or patients with HR-negative breast cancer, there was no significant difference in OS between patients with or without the long allele. In premenopausal women with HR-positive cancers, adequate intensity adjuvant chemotherapy did not achieve a greater OS rate than suboptimal chemotherapy in patients with the long allele, but it resulted in a significantly higher OS rate (p= .011) than suboptimal chemotherapy in women without the long allele.

CONCLUSIONS

The CYP19 TTTA repeat polymorphism is associated with survival in premenopausal women, but not in postmenopausal women, with HR-positive breast cancers. Premenopausal women with the long allele have a greater survival rate and may not gain benefit from adjuvant chemotherapy.

Axillary surgery in breast cancer patients

Surgeons have routinely removed ipsilateral axillary lymph nodes from women with breast cancer for over 100 years. The procedure provides important staging information, enhances regional control of the malignancy and may improve survival. As screening of breast cancer has increased, the mean size of newly diagnosed primary invasive breast cancers has steadily decreased and so has the number of women with lymph node metastases. Recognising that the therapeutic benefit of removing normal nodes may be low, alternatives to the routine level I/II axillary lymph node dissection have been sought. A decade ago sentinel lymph node biopsy (SLNB) was introduced. Because of its high accuracy and relatively low morbidity, this technique is now widely used to identify women with histologically involved nodes prior to the formal axillary node dissection. Specifically, SLNB has allowed surgeons to avoid a formal axillary lymph node biopsy in women with histologically uninvolved sentinel nodes, while identifying women with involved sentinel nodes who derive the most benefit from a completion axillary node dissection. Despite the increasing use of SLNB for initial management of the axilla in women with breast cancer, important questions remain regarding patient selection criteria and optimal surgical methods for performing the biopsy. This article discusses the evolution of axillary node surgery for women with breast cancer.

Neoadjuvant Systemic Therapy and the Surgical Management of Breast Cancer

Neoadjuvant chemotherapy is standard management for women who have locally advanced or inflammatory breast cancer, but can be applied to all women who may require postoperative chemotherapy for early-stage breast cancer. Disease-free survival and overall survival are equivalent between patients treated with neoadjuvant chemotherapy and patients treated with the same regimen postoperatively. Preoperative chemotherapy can offer women less morbid surgical treatment by down-staging both the primary breast tumor and axillary metastases. Finally, response to chemotherapy can inform clinicians of the chemosensitivity of the tumor, and can predict long-term outcome for women who have breast cancer.

Sentinel lymph node biopsy as the new standard of care in the surgical treatment for breast cancer

During the recent years, based on the results of validation studies, the sentinel lymph node biopsy has replaced routine axillary dissection as the new standard of care in early breast cancer. The technique represents a minimally invasive, highly accurate method for axillary staging, which could spare approximately 65-70% of patients unnecessary axillary dissection and its related morbidity. Several technical and clinical controversies have been raised during the development of this new technique; the authors review the most important issues, some questions have already been answered and others are still under debate. As far as the technical aspects are concerned, mapping techniques, appropriate surgical training, options for pathological examination of sentinel lymph nodes and the issue of nonaxillary sentinel lymph nodes are discussed. An update on clinical controversies demonstrates that factors such as large tumor size, palpable axillary nodes, multifocality and multicentricity, previous breast and axillary surgery, and pregnancy are no longer regarded as absolute contraindications for sentinel lymph node biopsy. Feasibility, accuracy and timing of sentinel lymph node biopsy in patients undergoing neoadjuvant chemotherapy remain unsolved issues, as well as the indication of the technique for some subgroups of in situ lesions. Finally, one of the most attractive open forums for debate will be discussed: whether or not completion of axillary dissection in the case of positive SLN is always required.

Multifocality and multicentricity are not contraindications for sentinel lymph node biopsy in breast cancer surgery

BACKGROUND

After the availability of the results of validation studies, the sentinel lymph node biopsy (SLNB) has replaced routine axillary dissection (AD) as the new standard of care in early unifocal breast cancers. Multifocal (MF) and multicentric (MC) tumors have been considered a contraindication for this technique due to the possible incidence of a higher false-negative rate. This prospective study evaluates the lymphatic drainage from different tumoral foci of the breast and assesses the accuracy of SLNB in MF-MC breast cancer.

PATIENTS AND METHODS

Patients with preoperative diagnosis of MF or MC infiltrating and clinically node-negative (cN0) breast carcinoma were enrolled in this study. Two consecutive groups of patients underwent SLN mapping using a different site of injection of the radioisotope tracer: a) "2ID" Group received two intradermal (i.d.) injections over the site of the two dominant neoplastic nodules. A lymphoscintigraphic study was performed after each injection to evaluate the route of lymphatic spreading from different sites of the breast. b) "A" Group had periareolar (A) injection followed by a conventional lymphoscintigraphy. At surgery, both radioguided SLNB (with frozen section exam) and subsequent AD were planned, regardless the SLN status.

RESULTS

A total 31 patients with MF (n = 12) or MC (n = 19) invasive, cN0 cancer of the breast fulfil the selection criteria. In 2 i.d. Group (n = 15) the lymphoscintigraphic study showed the lymphatic pathways from two different sites of the breast which converged into one major lymphatic trunk affering to the same SLN(s) in 14 (93.3%) cases. In one (6.7%) MC cancer two different pathways were found, each of them affering to a different SLN. In A Group (n = 16) lymphoscintigraphy showed one (93.7%) or two (6.3%) lymphatic channels, each connecting areola with one or more SLN(s). Identification rate of SLN was 100% in both Groups. Accuracy of frozen section exam on SLN was 96.8% (1 case of micrometastasis was missed). SLN was positive in 13 (41.9%) of 31 patients, including 4 cases (30.7%) of micrometastasis. In 7 of 13 (53.8%) patients the SLN was the only site of axillary metastasis. SLNB accuracy was 96.8% (30 of 31), sensitivity 92.8 (13 of 14), and false-negative rate 7.1% (1 of 14). Since the case of skip metastasis was identified by the surgeon intraoperatively, it would have been no impact in the clinical practice.

CONCLUSION

Our lymphoscintigraphic study shows that axillary SLN represents the whole breast regardless of tumor location within the parenchyma. The high accuracy of SLNB in MF and MC breast cancer demonstrates, according with the results of other series published in the literature, that both MF and MC tumors do not represent a contraindication for SLNB anymore.

Prognostic Relevance of Basal Cytokeratin Expression in Operable Breast Cancer

OBJECTIVE

We investigated whether basal cytokeratin (CK5/6 or CK17) expression had an impact on survival in patients with operable breast cancer.

METHODS

Expression of CK5/6 or CK17 was analyzed by immunohistochemistry in 195 women with breast cancer.

RESULTS

In total, 72 (37%) tumor samples were regarded as being positive for CK5/6 or CK17. The basal-like phenotype as defined by basal cytokeratin expression, lack of estrogen receptor (ER) and absence of HER2 overexpression was found in 48 (25%) cases. Positive staining for CK5/6 or CK17 was associated with worse prognosis when compared with patients negative for basal cytokeratins in all cases (5-year cancer-specific survival rate 59.4 vs. 77.5%, p = 0.0273) and in the node-negative group (70.5 vs. 90.8%, p = 0.0208) but not in the node-positive group (43.9 vs. 65.4%, p = 0.1182). To determine the real prognostic value of basal cytokeratins, survival in a group of ER-negative patients was analyzed depending on CK5/6 or CK 17 expression. No influence on survival was observed. The outcome of patients whose cancers were positive for cyclin E regardless of ER status was not changed by CK5/6 or CK17 expression. In multivariate analysis, independent prognostic factors affecting survival in the whole group included: nodal involvement, HER2 status and cyclin E expression. Neither ER status nor basal cytokeratin expression retained statistical significance.

CONCLUSION

We demonstrated that the poor prognosis associated with the basal-like phenotype of breast cancer was determined by ER absence and cyclin E expression and not by CK5/6 or CK17 expression.

Compliance with guidelines is related to better local recurrence-free survival in ductal carcinoma in situ

The aim was to study the effect of compliance with guidelines on local recurrence (LR)-free survival in patients treated for ductal carcinoma in situ (DCIS). From January 1992 to December 2003, 251 consecutive patients had been treated for DCIS in two hospitals in the North Netherlands. Every case in this two-hospital sample was reviewed in retrospect for its clinical and pathological parameters. It was determined whether treatment had been carried out according to clinical guidelines, and outcomes in follow-up were assessed. In addition, all patients treated for DCIS in this region (n=1389) were studied regarding clinical parameters, in order to determine whether the two-hospital sample was representative of the entire region. In the two-hospital sample, 31.4% (n=79) of the patients had not been treated according to the guidelines. Positive margins were associated with LR (hazard ratio (HR)=4.790, 95% confidence interval (CI) 1.696–13.531). Breast-conserving surgery and deviation from the guidelines were independent predictors of LR (HR=7.842, 95% CI 2.126–28.926; HR=2.778, 95% CI 0.982–6.781, respectively). Although the guidelines changed over time, time was not a significant factor in predicting LRs (HR=1.254, 95% CI 0.272–5.776 for time period 1992–1995 and HR=1.976, 95% CI 0.526–7.421 for time period 1996–1999). Clinical guidelines for the treatment of patients with DCIS have been developed and updated from existing literature and best evidence. Compliance with the guidelines was an independent predictor of disease-free survival. These findings support the application of guidelines in the treatment of DCIS.

Prescription pattern of aromatase inhibitors in the adjuvant setting in Germany--final results of a survey among german breast cancer specialists

INTRODUCTION

The prescription practice of adjuvant therapy with aromatase inhibitors (AI) in Germany is not known, also considering that approval is still limited or awaited. We conducted a survey among breast specialists of the German Society of Senology.

METHOD

A standardized questionnaire and the latest abstracts of the 3 trials were sent out to 1,223 members, responses were anonymized. All questions were to be answered with respect to the patients' national health insurance (NHS) or private health insurance (PHS) status.

RESULTS

Questionnaire were predominantly completed by gynecologists (82.4%). In all, >16,000 breast cancer patients had been treated in 2003. A total of 69.4% of physicians initiated adjuvant AI in up to 25% of NHS patients, 5.6% treated >50% of patients. However, 10.3% of physicians treated >50% of their PHS patients with an AI. Under the hypothesis of an unrestricted label for AI, 44.5% of physicians would treat >50% patients. The switch to an AI after 2-3 years of tamoxifen was chosen in 22% for NHS patients and in 36% of PHS patients. Continuing an AI after 5 years of tamoxifen was favored. in 26% of NHS and 35% of PHS patients.

CONCLUSION

Tamoxifen as the previous gold standard is being replaced by AI; a dramatic change in treatment pattern is expected with less restricted approval.

Cathepsin D-related Disease-free Interval in pT1 Primary Breast Carcinomas: A Pilot Study

In order to address the heterogeneity of the pT1 breast cancer stages, we have been examining the natural and the clinical course of disease in relation to cathepsin D expression, as a molecular marker for the tumor progression that leads to metastasis. The original aim of our pilot study was to determine whether it was possible to distinguish high-risk from low-risk patients, on the basis of nonestrogen- vs. estrogen-regulated cathepsin D expression. Our results showed that estrogen-regulated cathepsin D expression could be useful as surrogate marker of node-positive status. Further, during the natural course of disease, none of 7 pT1N0 patients with tumors bearing nonestrogen-regulated cathepsin D expression developed metastasis. During the clinical course of disease, nonestrogen-regulated cathepsin D expression defined low-risk while estrogen-regulated cathepsin D expression defined high-risk pT1N+ subgroup of patients. Although there is no consensus with respect to metastasis-related prognostic value of cathepsin D expression, our pilot study implies its prognostic value in pT1 breast cancer patients and supports the hypothesis that cathepsin D may promote metastasis in this early stage of disease.

Population-based validation of the prognostic model ADJUVANT! for early breast cancer

PURPOSE

Adjuvant! (www.adjuvantonline.com) is a web-based tool that predicts 10-year breast cancer outcomes with and without adjuvant systemic therapy, but it has not been independently validated.

METHODS

Using the British Columbia Breast Cancer Outcomes Unit (BCOU) database, demographic, pathologic, staging, and treatment data on 4,083 women diagnosed between 1989 and 1993 in British Columbia with T1-2, N0-1, M0 breast cancer were abstracted and entered into Adjuvant! to calculate predicted 10-year overall survival (OS), breast cancer-specific survival (BCSS), and event-free survival (EFS) for each patient. Individual BCOU observed outcomes at 10 years were independently determined. Predicted and observed outcomes were compared.

RESULTS

Across all 4,083 patients, 10-year predicted and observed outcomes were within 1% for OS, BCSS, and EFS (all P > .05). Predicted and observed outcomes were within 2% for most demographic, pathologic, and treatment-defined subgroups. Adjuvant! overestimated OS, BCSS, and EFS in women younger than age 35 years (predicted-observed = 8.6%, 9.6%, and 13.6%, respectively; all P < .001) or with lymphatic or vascular invasion (LVI; predicted-observed = 3.6%, 3.8%, and 4.2%, respectively; all P < .05); these two prognostic factors were not automatically incorporated within the Adjuvant! algorithm. After adjusting for the distribution of LVI, using the prognostic factor impact calculator in Adjuvant!, 10-year predicted and observed outcomes were no longer significantly different.

CONCLUSION

Adjuvant! performed reliably. Patients younger than age 35 or with known additional adverse prognostic factors such as LVI require adjustment of risks to derive reliable predictions of prognosis without adjuvant systemic therapy and the absolute benefits of adjuvant systemic therapy.

Cyclin E Expression in Operable Breast Cancer Quantified Using Real-Time RT–PCR: A Comparative Study with Immunostaining

OBJECTIVE

The main purpose of this retrospective study was to compare cyclin E expression levels in operable breast cancer patients determined using real-time RT-PCR and immunostaining. The prognostic relevance of cyclin E was also investigated.

METHODS

Specimens of invasive ductal breast cancer tissues obtained from 124 women during radical mastectomy were analyzed.

RESULTS

Of the tumor samples, 40.3 and 59.7% showed high expression of cyclin E in RT-PCR and immunostaining, respectively. The overall agreement probability was 0.032 according to Scott's pi statistic. With a median follow-up of 55.5 months, cyclin E expression assessed using immunostaining was an independent negative prognostic factor in the node positive group (hazard ratio 3.1; 95% CI 1.0-9.2; P = 0.045). Cyclin E expression correlated with absence of steroid receptors and younger age. RT-PCR results did not predict survival in any group of patients.

CONCLUSIONS

Disagreement between real-time RT-PCR and immunostaining was demonstrated. Immunostaining seems to be the more reliable method for assessing cyclin E in breast cancer cells.