Prognosis and Management of Patients With Node-Negative Invasive Breast Carcinoma That Is 1 cm or Smaller in Size (stage 1; T1a,bN0M0): A Review of the Literature

Mitochondrial DNA content varies with pathological characteristics of breast cancer

Changes in mitochondrial DNA (mtDNA) content in cancers have been reported with controversial results, probably due to small sample size and variable pathological conditions. In this study, mtDNA content in 302 breast tumor/surrounding normal tissue pairs were evaluated and correlated with the clinico-pathological characteristics of tumors. Overall, mtDNA content in tumor tissues is significantly lower than that in the surrounding normal tissues, P < 0.00001. MtDNA content in tumor tissues decreased with increasing tumor size. However, when the tumor is very large (>50 cm³), mtDNA content started to increase. Similarly, mtDNA content decreased from grades 0 and I to grade II tumors, but increased from grade II to grade III tumors. Tumors with somatic mtDNA alterations in coding region have significantly higher mtDNA content than tumors without somatic mtDNA alterations (P < 0.001). Tumors with somatic mtDNA alterations in the D-Loop region have significantly lower mtDNA content (P < 0.001). Patients with both low and high mtDNA content in tumor tissue have significantly higher hazard of death than patients with median levels of mtDNA content. mtDNA content in tumor tissues change with tumor size, grade, and ER/PR status; significant deviation from the median level of mtDNA content is associated with poor survival.

Chemotherapy with or without trastuzumab

The prognosis of pT1N0M0/stage I breast cancer has generally been considered so favourable that these patients are not routinely offered adjuvant systemic therapy. However, biological heterogeneity within pT1N0M0 dictates diverse outcomes within the subgroup. HER2 gene amplification or protein overexpression is uncommon in pT1N0M0 disease, but, when present, is clearly associated with a higher risk of recurrence. The role of anti-HER2 therapy in these patients is controversial. Few women with node-negative, small tumours were included in the adjuvant trastuzumab trials. There are no robust data on trastuzumab in this patient subset, although subgroup analyses suggest that proportional benefits are independent of T and N. With current guidelines and scheduling, committing to adjuvant trastuzumab involves concurrent chemotherapy, 1 year of treatment and potential cardiotoxicity. A further challenge with anti-HER2 therapy is the potential benefit in patients with demonstrable HER2 positivity within a predominantly HER2-negative tumour. The decision for therapy requires a yes/no answer, but HER2 status derives from a continuum of gene copy number and protein expression. The diagnostic threshold is made more complex by heterogeneity of the HER2 status within a tumour. This review focuses on available data for HER2-positive pT1N0M0 disease and explores the significance of intratumoural HER2 heterogeneity.

Age and associated fibrocystic changes are prognostically significant in patients with small node-negative (T1a,bN0) invasive breast cancer

Some patients with small (≤1.0 cm) node-negative (T1a,bN0) invasive breast cancer (IBC) who undergo only local therapy experience recurrences. There is limited information on prognostic factors in these patients. We sought to identify prognostic factors associated with disease-free survival (DFS) and overall survival (OS) in patients with T1a,bN0 IBC. Histologic sections from 273 T1a,bN0 IBC patients treated at M. D. Anderson Cancer Center (MDACC) between 1980 and 1999 were reviewed. Microscopic tumor size; multifocality; histologic type, grade of tumor; presence, type, grade of associated ductal carcinoma in situ (DCIS); presence of fibrocystic changes (FCC) with/without atypia; and lymphovascular invasion were identified. The Kaplan-Meier method was used to evaluate DFS and OS. Median patient age was 58 years, median follow-up period was 10.8 years, and median tumor size was 0.8 cm. Multifocal disease was identified in 26% of cases. At 10 years, the DFS and OS rates were 91% and 88%, respectively. Twenty-one percent of patients had extensive (>50%), and 30% had grade 3 DCIS. Nonproliferative FCC and proliferative FCC with/without atypia were present in 80%, 36%, and 38% of patients, respectively. In univariate analysis, age at diagnosis (p < 0.0001), grade (p = 0.015), and percent (p = 0.046) of DCIS were significantly associated with DFS; presence of FCC was associated with longer DFS and OS. In multivariable models, age and presence of FCC remained significantly associated with survival. Age at diagnosis and associated FCC are significant factors in predicting recurrence in patients with T1a,bN0 IBC. Adjuvant systemic therapy should be discussed with and considered for young patients with T1a,bN0 IBC.

Impact of a commercial reference laboratory test recurrence score on decision making in early-stage breast cancer

PURPOSE

To investigate whether recurrence score (RS) as determined using a commercial reference laboratory test influences clinicians' treatment recommendations and eventual treatment in patients with early-stage breast cancer.

METHODS

A retrospective analysis was performed on 74 patients from a community-based oncology practice with estrogen receptor (ER) -positive, lymph node (LN) -negative stage I or II breast cancer for which RS was obtained. Demographic and pathology information was extracted from medical records. Ten-year relapse-free survival was calculated using Adjuvant! Online. Treatment recommendations before the RS knowledge were compared with treatment recommendations after RS knowledge and to the treatment eventually administered.

RESULTS AND CONCLUSION

A weak correlation was found between RS and both patient age and tumor size, modest correlation between RS and tumor grade, and modest correlation between RS and 10-year recurrence as determined by Adjuvant! Online. For 21% and 25% of patients, knowledge of the RS changed the clinicians' treatment recommendations and eventual treatment, respectively. The decision to change from hormone therapy to chemotherapy (with or without hormone therapy) was generally associated with high RS (high distant recurrence risk as determined by the commercial reference laboratory test), whereas the decision to change from chemotherapy to hormone therapy was generally associated with low RS (low distant recurrence risk as determined by the commercial reference laboratory test). Knowledge of the RS changed treatment recommendations and eventual treatment in patients with ER-positive/LN-negative early-stage breast cancer. Use of genomic-based prognosis may result in more accurate estimates of true recurrence risk than currently possible with commonly used prognostic factors (such as patient age, tumor size, and tumor grade) alone and thus lead to an increase in appropriate adjuvant therapy decision making.

Pathological and mammographic prognostic factors for screen detected cancers in a multi-centre randomised, controlled trial of mammographic screening in women from age 40 to 48 years

AIM

To assess pathological and radiological prognostic factors for cancers detected by screening within a multi-centre RCT trial of mammographic screening of younger women.

METHOD

The survival of 232 women with screen detected invasive cancer was ascertained. Data on invasive cancer size, histological grade, nodal status, vascular invasion, mammographic spiculation, comedo calcification and mammographic background were assessed. Kaplan-Meier and Cox proportional hazards methods were used to examine survival.

RESULTS

Univariate analysis indicated that women with cancers with the following features had poorer survival; ≥ 30 mm, histologically grade 3, heavily node positive (4 or more positive nodes), vascular invasion positive and displaying mammographic comedo calcification. In a multivariate model survival remained poorer in women with four or more nodes positive (HR 8.36, 95% CI 2.31, 30.17) and in those with comedo calcification (HR 3.00,95% CI 1.13, 7.99).

CONCLUSION

Nodal status and the presence of mammographic comedo calcification have independent prognostic significance in young women with screen detected cancer.

Correlation of the ratio of metastatic to non-metastatic cancer cases with the degree of socioeconomic deprivation among Texas counties

BACKGROUND

Previous studies have demonstrated that cancer registrations and hospital discharge rate are closely correlated with census data-based socioeconomic deprivation indices. We hypothesized that communities with higher degrees of socioeconomic deprivation tend to have a higher ratio of metastatic to non-metastatic cancer cases (lung, breast, prostate, female genital system, colorectal cancers or all types of cancers combined). In this study, we investigate the potential link between this ratio and the Wellbeing Index (WI) among Texas counties.

RESULTS

Cancer data in 2000 were provided by the Texas Cancer Registry, while data on the ten socioeconomic variables among the 254 Texas counties in 2000 for building the WI were obtained from U.S. Census Bureau. The ten socioeconomic status variables were subjected to the principal component analysis, and the first principal component scores were grouped into deciles for the WI (1 to 10) and the 254 Texas counties were classified into 10 corresponding groups. Weighted linear regression analyses and a Cochran-Armitage trend test were performed to determine the relationship between the ratio of age-adjusted metastatic to non-metastatic cancer incidence cases and WI. The ratios of metastatic to non-metastatic cases of female genital system cancer (r2 = 0.84, p = 0.0002), all-type cancers (r2= 0.73, p = 0.0017) and lung cancer (r2= 0.54, p = 0.0156) at diagnosis were positively correlated with WI.

CONCLUSIONS

The ratios of metastatic to non-metastatic cases of all-type, female genital system and lung cancers at diagnosis were statistically correlated with socioeconomic deprivation. Potential mediators for the correlation warrant further investigation in order to reduce health disparities associated with socioeconomic inequality.

Should Histologic Grade Be Incorporated into the TNM Classification System for Small (T1, T2) Node-Negative Breast Adenocarcinomas?

Prognosis of invasive ductal carcinoma (IDC) strongly correlates with tumor grade as determined by Nottingham combined histologic grade. While reporting grade as low grade/favorable (G1), intermediate grade/moderately favorable (G2), and high grade/unfavorable (G3) is recommended by American Joint Committee on Cancer (AJCC) staging system, existing TNM (Primary Tumor/Regional Lymph Nodes/Distant Metastasis) classification does not directly incorporate these data. For large tumors (T3, T4), significance of histologic grade may be clinically moot as those are nearly always candidates for adjuvant therapy. However, for small (T1, T2) node-negative (N0) tumors, grade may be clinically relevant in influencing treatment decisions, but data on outcomes are sparse and controversial. This retrospective study analyzes clinical outcome in patients with small N0 IDC on the basis of tumor grade. Our results suggest that the grade does not impact clinical outcome in T1N0 tumors. In T2N0 tumors, however, it might be prognostically significant and relevant in influencing decisions regarding the need for additional adjuvant therapy and optimal management.

Histopathological prognostic factors in early breast carcinoma: an evaluation of cell proliferation in carcinoma cells

Early breast carcinoma is defined as pathological stage 1 (pT1N0M0) tumour and its incidence has recently increased possibly due to the advent of mammography based mass screening. Overall survival of these patients is in general excellent, but more than 20% of them will eventually develop distant metastasis and die. Therefore, an establishment of prognostic factors could contribute greatly to determining the algorithm for treating these patients after surgery. Histopathological prognostic factors still play pivotal roles in the management of these patients. Among these, Nottingham histological grade is considered the gold standard for determining the clinical outcome of early breast cancer patients if done in optimally processed tissue specimens by well-trained pathologists. Among these histological factors of Nottingham histological grade, mitotic index has been demonstrated to provide the most significant information as to prognosis of these patients. Attempts have been made to assess the status of tumour cell proliferation in practical, reproducible and accurate manners in the past. Among these attempts, immunohistochemical analysis of cell cycle associated nuclear antigens, especially Ki67/MIB1 labelling index in archival materials, has been reported to provide clinically inert and significant information. However, its methodologies, including processing of the specimens, and modes of interpretation should be standardised before this Ki67/MIB1 labelling index can become incorporated into routine clinical practice in the management of early breast carcinoma patients.

Subcellular localization of the HER4 intracellular domain, 4ICD, identifies distinct prognostic outcomes for breast cancer patients

Conflicting reports of the prognostic value of HER4 in breast cancer may be explained by distinct activities of the HER4 intracellular domain, 4ICD. Here, immunohistochemical 4ICD staining of archival invasive breast cancers (n = 923) was scored separately for nuclear and cytosolic expression, and these data were tested for associations with clinicopathological markers, disease-free survival, and disease-specific survival. By univariate analysis, cytosolic 4ICD expression was independently associated with estrogen receptor and progesterone receptor expression and tumor cell apoptosis. Nuclear 4ICD inversely correlated with tumor grade and tumor mitosis. In multivariate analyses cytosolic, but not nuclear 4ICD, significantly correlated with disease-free survival (P = 0.035) and disease-specific survival (P < 0.004) in lymph node-negative patients. Our results demonstrate for the first time that cytosolic 4ICD has significant positive prognostic value in node-negative breast cancer patients. At present, tumor grade and size are the primary clinicopathological parameters commonly used to guide decision making in these patients. Our results suggest that cytosolic 4ICD has important pathological functions and may be used to identify node-negative breast cancer patients at low risk of relapse and an improved survival, thereby avoiding systemic overtreatment of these patients. Our results also suggest that pan-receptor tyrosine kinase inhibitors, currently in clinical trials, or HER4 antagonists, which disengage 4ICD signaling, may have untoward activity in patients whose tumors express cytosolic 4ICD.

Lymphovascular invasion and lobular histology are associated with increased incidence of isolated tumor cells in sentinel lymph nodes from early-stage breast cancer patients

BACKGROUND

Isolated tumor cells (ITC) are more likely to be identified when serial sectioning and immunohistochemical staining are used to evaluate sentinel lymph nodes (SLN). Our goal was to identify clinicopathologic features associated with ITC in patients undergoing sentinel lymph node dissection (SLND).

METHODS

We reviewed clinicopathologic data for 3557 patients with no clinical evidence of lymph node metastases undergoing SLND between November 1993 and March 2007. Patients were staged according to the 6th edition of the American Joint Committee on Cancer staging system, with metastasis <or=.2 mm classified as ITC.

RESULTS

A SLN was identified in 3475 patients (97.7%), including 2518 (72.4%) with negative nodes and 169 (4.9%) with ITC. A statistically significant association existed between lobular histology and the identification of ITC; 13.6% of patients with ITC had lobular histology versus 7.3% of patients with a negative SLN (P = .003). The presence of lymphovascular invasion (LVI) was also associated with ITC; 18.3% of patients with ITC had LVI in the primary tumor versus 8.5% of patients with a negative SLN (P < .001). No difference existed between patients with and without ITC with respect to T stage, grade, estrogen receptor, progesterone receptor, HER2/neu status, or biopsy method.

CONCLUSION

The association between ITC and LVI, a known predictor of poor outcome, suggests ITC may have clinical relevance. The relationship between lobular histology and ITC is consistent with the known pattern of lobular metastases, which frequently present as small foci requiring immunohistochemistry for detection. Longer follow-up is needed to determine whether ITC have prognostic significance.

REG1A expression is an independent factor predictive of poor prognosis in patients with breast cancer

BACKGROUND

Regenerating gene I alpha (REG1A) is a growth factor known to affect pancreatic islet beta cells. Although REG1A expression has also been observed in various malignant tumors, the correlation between REG1A expression and the clinicopathological characteristics of breast cancer and patient prognosis has not been evaluated.

METHODS

Resected breast cancer tissues obtained at surgery from 150 breast cancer patients was stained with anti-REG1A antibody, after which the relative area occupied by stained tumor cells was evaluated under a light microscope and correlated with known clinicopathological factors.

RESULTS

Whereas tumor cells were frequently stained with anti-REG1A antibody, cells from normal breast tissue were not stained. REG1A expression in tumors of breast cancer patients with HER2-positive disease was higher than those with HER2-negative disease (P = .0009). The 10-year disease-specific survival rate among patients with lower levels of REG1A was significantly better than among those with higher levels (P = .0002 by log rank test). Multivariate Cox proportional hazard analyses revealed REG1A (hazard ratio, 2.07; 95% confidence interval, 1.93 to 11.29; P = .0005) and axillary lymph node status (hazard ratio, 4.44; 95% confidence interval, 1.52 to 11.29; P = .0003) to be independent factors affecting the 10-year disease-specific survival rate.

CONCLUSION

High levels of REG1A expression within tumors are an independent predictor of poor prognosis in patients with breast cancer.

Prognostic significance of Nottingham histologic grade in invasive breast carcinoma

PURPOSE

The three strongest prognostic determinants in operable breast cancer used in routine clinical practice are lymph node (LN) stage, primary tumor size, and histologic grade. However, grade is not included in the recent revision of the TNM staging system of breast cancer as its value is questioned in certain settings.

MATERIALS AND METHODS

This study is based on a large and well-characterized consecutive series of operable breast cancer (2,219 cases), treated according to standard protocols in a single institution, with a long-term follow-up (median, 111 months) to assess the prognostic value of routine assessment of histologic grade using Nottingham histologic grading system.

RESULTS

Histologic grade is strongly associated with both breast cancer-specific survival (BCSS) and disease-free survival (DFS) in the whole series as well as in different subgroups based on tumor size (pT1a, pT1b, pT1c, and pT2) and LN stages (pN0 and pN1 and pN2). Differences in survival were also noted between different individual grades (1, 2, and 3). Multivariate analyses showed that histologic grade is an independent predictor of both BCSS and DFS in operable breast cancer as a whole as well as in all studied subgroups.

CONCLUSION

Histologic grade, as assessed by the Nottingham grading system, provides a strong predictor of outcome in patients with invasive breast cancer and should be incorporated in breast cancer staging systems.

Sentinel lymph node biopsy in women with pT1a or "microinvasive" breast cancer

The role of sentinel lymph node biopsy (SLNB) in pT1a and "microinvasive" breast cancer has not been extensively studied. We report our experience with SLNB in patients with "minimal" breast cancer to determine the incidence and type of SLN metastases, and to study the potential impact on their surgical or oncological management. Among some 3387 women operated upon for primary breast cancer who underwent sentinel lymph node biopsy at nine institutions participating in the Rome Breast Cancer Study Group, 251 were staged pT1a or pT1mic (7.4%). There were 13 cases of sentinel lymph node metastases identified in this group of patients (5.2%), seven macrometastases and six micrometastases. Additionally, ITC were diagnosed by immunohistochemistry in four cases (1.6%). The incidence of SLN metastases was 7/174 (4%) and 6/77 (7.8%) in patients with pT1a and pT1mic tumors, respectively (p=0.2). Age and histological grade were predictive factors for SLN metastases. Chemotherapy was seldom directed by axillary node status (8/38 patients). As the incidence of SLN metastases in these patients is very small, particularly in the pT1a group, the indications for even a minimally invasive procedure, such as sentinel lymph node biopsy, should be probably individualized.

Implications of applied research for prognosis and therapy of breast cancer

Breast cancer is the one of leading causes of cancer-related deaths in women within economically developed regions of the world. The heterogeneity of the natural history of breast cancer complicates patient management in that there is tremendous variability in response to treatment and for survival. More recently, several biomarkers (hormone receptor status and HER2 expression) have been added to the risk evaluation and therapeutic assessments. Evolving knowledge of molecular biology and newer techniques, such as genomics and proteomics, offer the potential to better define the biologic nature of the disease process, both for risk and therapy. This review discusses classical as well as new prognostic and predictive techniques. These are leading to a paradigm shift from empirical treatment to an individually tailored approach, which may soon become a realistic option for patients, based on specific molecular profiles.

Prognostic relevance of proliferative activity evaluated by Mib-1 immunostaining in node negative breast cancer

AIM

The purpose of this prospective observational study was to analyze the role of Mib-1 immunostaining as a proliferation index in breast cancer. Correlations between Mib-1 expression and clinico-pathological characteristics as well as its prognostic value have been studied in a series of 432 node negative breast cancers.

METHODS

Mib-1 expression was evaluated by immunohistochemistry. Tumor sections from highly cellular invasive areas of cancer were stained by monoclonal antibody Mib-1 (Dako) and cells whose nuclei stained positive were counted in 10 randomly chosen HPFs and expressed as percentages of all epithelial cells. A minimum of 400 cells were counted. Correlation between Mib-1 staining and clinico-pathological factors was investigated by means of univariate and multivariate analyses. The prognostic impact on actuarial disease free (DFS) and overall survival (OS) was evaluated by univariate analysis using the log-rank test and by multivariate analysis using Cox regression model.

RESULTS

Tumors were considered as positive for Mib-1 expression when more than 15% of cells counted were stained. Mib-1 positivity was found in 190/432 cases and resulted in being significantly related to tumor grade, tumor size and absence of estrogen receptors at multivariate analysis. With a median follow-up of 66 months, Mib-1 positivity resulted in being the only independent predictor of OS (RR 2.92), and an independent predictor of DFS (RR 2.01) together with absence of estrogen receptors (RR 2.15).

CONCLUSIONS

Mib-1 index of proliferative activity correlates well to other established prognostic factors of breast cancer. Mib-1 index may improve the tailoring of adjuvant therapy in early breast cancer, and our experience adds evidence to its effectiveness as prognostic factor. Efforts to reach uniformity in the methodology and in the scoring system should be done to warrant a standardized procedure and make Mib-1 determination definitively reliable in the current clinical practice.

RNA extraction from ten year old formalin-fixed paraffin-embedded breast cancer samples: a comparison of column purification and magnetic bead-based technologies

BACKGROUND

The development of protocols for RNA extraction from paraffin-embedded samples facilitates gene expression studies on archival samples with known clinical outcome. Older samples are particularly valuable because they are associated with longer clinical follow up. RNA extracted from formalin-fixed paraffin-embedded (FFPE) tissue is problematic due to chemical modifications and continued degradation over time. We compared quantity and quality of RNA extracted by four different protocols from 14 ten year old and 14 recently archived (three to ten months old) FFPE breast cancer tissues. Using three spin column purification-based protocols and one magnetic bead-based protocol, total RNA was extracted in triplicate, generating 336 RNA extraction experiments. RNA fragment size was assayed by reverse transcription-polymerase chain reaction (RT-PCR) for the housekeeping gene glucose-6-phosphate dehydrogenase (G6PD), testing primer sets designed to target RNA fragment sizes of 67 bp, 151 bp, and 242 bp.

RESULTS

Biologically useful RNA (minimum RNA integrity number, RIN, 1.4) was extracted in at least one of three attempts of each protocol in 86-100% of older and 100% of recently archived ("months old") samples. Short RNA fragments up to 151 bp were assayable by RT-PCR for G6PD in all ten year old and months old tissues tested, but none of the ten year old and only 43% of months old samples showed amplification if the targeted fragment was 242 bp.

CONCLUSION

All protocols extracted RNA from ten year old FFPE samples with a minimum RIN of 1.4. Gene expression of G6PD could be measured in all samples, old and recent, using RT-PCR primers designed for RNA fragments up to 151 bp. RNA quality from ten year old FFPE samples was similar to that extracted from months old samples, but quantity and success rate were generally higher for the months old group. We preferred the magnetic bead-based protocol because of its speed and higher quantity of extracted RNA, although it produced similar quality RNA to other protocols. If a chosen protocol fails to extract biologically useful RNA from a given sample in a first attempt, another attempt and then another protocol should be tried before excluding the case from molecular analysis.

Overall survival and cause-specific mortality of patients with stage T1a,bN0M0 breast carcinoma

PURPOSE

With mammographic screening, the frequency of diagnosis of stage T1a,bN0M0 breast cancer has increased. Prognosis after locoregional therapy and benefit from adjuvant systemic therapy are poorly defined. We reviewed T1a,bN0M0 breast cancer cases registered in the Surveillance, Epidemiology, and End Results (SEER) Program to investigate the impact of prognostic factors on breast cancer-specific (BCSM) and non-breast cancer-related mortality.

METHODS

We identified T1a,bN0M0 breast cancer cases registered in the SEER Program from 1988 to 2001, and used the Kaplan-Meier product limit method to describe overall survival (OS). We estimated the probabilities of death resulting from breast cancer and from other causes, and analyzed associations of patient and tumor characteristics with OS, BCSM, and non-breast cancer-related mortality using the log-rank test, Cox proportional hazards models, and a competing-risk model. We constructed nomograms to assist physicians in adjuvant therapy decision making.

RESULTS

We identified 51,246 T1a,bN0M0 cases. Median follow-up was 64 months (range, 1 to 167 months). Median age at diagnosis was 65 years (range, 20 to 101 years). Ten-year probabilities of all-cause mortality and BCSM were 24% and 4%, respectively. Characteristics associated with increased probability of BCSM included age younger than 50 years at diagnosis, high tumor grade, estrogen receptor-negative status, progesterone receptor-negative status, and fewer than six nodes removed at axillary dissection. The constructed nomograms allow a comparison of predicted breast cancer-specific survival and non-breast cancer-specific survival in individual patients.

CONCLUSION

Overall, the prognosis of patients with T1a,bN0M0 breast cancer is excellent. However, subgroups of patients who are at higher risk of BCSM and who should be considered for adjuvant systemic therapy can be identified.

Histologic grading is an independent prognostic factor in invasive lobular carcinoma of the breast

Invasive lobular carcinoma (ILC) comprises approximately 5-15% of breast cancers and appears to have a distinct biology. As it is less common than invasive ductal carcinoma, few studies of large size have addressed the value of assessment of histologic grade in ILC.

METHODS

This study is based on a large and well-characterised consecutive series of breast cancer (4,987 cases), from a single institution, with a long-term follow-up to assess the prognostic value of routine assessment of histologic grade in ILC. Histologic grade and other clinicopathological data were available in 517 pure ILC cases. A panel of biomarkers was also available for 215 cases.

RESULTS

The majority of ILC was of classical and mixed lobular variants (89%). Most ILC cases were moderately differentiated (grade 2) tumours (76%), while a small proportion of tumours were either grade 1 or 3 tumours (12% each). There were positive associations between histologic grade and other clinicopathological variables of poor prognosis such as larger size, positive lymph node, vascular invasion, oestrogen receptor and androgen receptor negativity and p53 positivity. Multivariate analyses showed that histologic grade is an independent predictor of shorter breast cancer specific survival and disease free interval.

CONCLUSION

Histologic grade of ILC, as assessed by the Nottingham grading system, provides a strong predictor of outcome in patients with invasive lobular carcinoma of the breast and should be provided routinely in pathology reports.

Unliganded estrogen receptor α inhibits breast cancer cell growth through interaction with a cyclin‐dependent kinase inhibitor (p21WAF1)

Estrogens are mitogenic in human breast cancer cells, but the presence of estrogen receptor alpha (ER alpha) is associated with a favorable prognosis in primary tumors and the molecular basis for this paradoxical relationship remains unknown. Here we show that ER alpha and ER alpha mutants devoid of ligand and DNA-binding domains inhibit cell growth in three-dimensional matrix as well as tumor formation in nude mice. Using in vitro and intracellular approaches, we have found that ER alpha, via its amino acids 184-283, interacts with cyclin-dependent kinase inhibitor p21(WAF1). Both proteins exhibit mutual interactions in the absence of estrogens or in the presence of pure antiestrogen ICI(182,780), whereas estradiol treatment disrupts their interactions. Cross-linking experiments reveal that these proteins are present in a larger complex of approximately 200 kDa that also contains cdk2 and cyclin E. We further demonstrate that the unliganded full-length ER alpha or the variant having the p21(WAF1) interaction region significantly increases p21(WAF1) expression, whereas ER alpha silencing reduces p21(WAF1) levels and silencing of p21(WAF1) is sufficient to prevent ER alpha-induced growth inhibition. Taken together, our results point to an antiproliferative function of the unliganded ER alpha through its physical interactions with p21(WAF1) that may also explain the favorable prognosis of ER alpha-positive breast cancers.

A multidisciplinary approach to the management of breast cancer, part 1: prevention and diagnosis

Breast cancer is the most common cancer among women in the United States, with an estimated 200,000 new cases diagnosed annually. A multidisciplinary focus that entails prevention, diagnosis, and treatment has led to significant strides in the reduction of breast cancer incidence and mortality. Additionally, breast cancer management has become increasingly complex, requiring comprehensive assessment and review of multiple issues that include the role of genetic testing, imaging and breast magnetic resonance imaging, surgical and reconstructive options, and a variety of new adjuvant therapies. It has become more evident that a multidisciplinary team approach that involves a spectrum of breast experts is necessary to provide optimal care to patients. This team includes medical oncologists, breast radiologists, breast pathologists, surgical breast specialists, radiation oncologists, geneticists, and primary care physicians. Furthermore, patient knowledge has increased use of the Internet, and more patients are seeking a multidisciplinary approach to treatment. This review considers information for health care professionals who will facilitate optimal patient care for women at increased risk for or presenting with a new diagnosis of breast cancer. The multidisciplinary team of authors, representing the different disciplines, has selected important state-of-the-art issues that arise in their daily practices for consideration, rather than summarizing what is already available in textbooks.

Trastuzumab (herceptin) for early-stage breast cancer

Breast cancer patients who have HER2 gene amplification and, consequently, protein overexpression, generally show an aggressive course with short disease-free and overall survivals. Trastuzumab, a humanized monoclonal antibody against the extracellular domain of HER2 protein, has been shown to benefit patients who have HER2-positive metastatic breast cancer, and recently, the results of five adjuvant trials involving more than 13,000 women have been released. Here, the authors summarize the main results and outline the differences among these trials, which have demonstrated an important role of trastuzumab in the treatment of women who have HER2-overexpressing/amplified early breast cancer.

Predictors of early relapse in postmenopausal women with hormone receptor-positive breast cancer in the BIG 1-98 trial

BACKGROUND

Aromatase inhibitors are considered standard adjuvant endocrine treatment of postmenopausal women with hormone receptor-positive breast cancer, but it remains uncertain whether aromatase inhibitors should be given upfront or sequentially with tamoxifen. Awaiting results from ongoing randomized trials, we examined prognostic factors of an early relapse among patients in the BIG 1-98 trial to aid in treatment choices.

PATIENTS AND METHODS

Analyses included all 7707 eligible patients treated on BIG 1-98. The median follow-up was 2 years, and the primary end point was breast cancer relapse. Cox proportional hazards regression was used to identify prognostic factors.

RESULTS

Two hundred and eighty-five patients (3.7%) had an early relapse (3.1% on letrozole, 4.4% on tamoxifen). Predictive factors for early relapse were node positivity (P < 0.001), absence of both receptors being positive (P < 0.001), high tumor grade (P < 0.001), HER-2 overexpression/amplification (P < 0.001), large tumor size (P = 0.001), treatment with tamoxifen (P = 0.002), and vascular invasion (P = 0.02). There were no significant interactions between treatment and the covariates, though letrozole appeared to provide a greater than average reduction in the risk of early relapse in patients with many involved lymph nodes, large tumors, and vascular invasion present.

CONCLUSION

Upfront letrozole resulted in significantly fewer early relapses than tamoxifen, even after adjusting for significant prognostic factors.