Selective genomic copy number imbalances and probability of recurrence in early-stage breast cancer

A number of studies of copy number imbalances (CNIs) in breast tumors support associations between individual CNIs and patient outcomes. However, no pattern or signature of CNIs has emerged for clinical use. We determined copy number (CN) gains and losses using high-density molecular inversion probe (MIP) arrays for 971 stage I/II breast tumors and applied a boosting strategy to fit hazards models for CN and recurrence, treating chromosomal segments in a dose-specific fashion (-1 [loss], 0 [no change] and +1 [gain]). The concordance index (C-Index) was used to compare prognostic accuracy between a training (n = 728) and test (n = 243) set and across models. Twelve novel prognostic CNIs were identified: losses at 1p12, 12q13.13, 13q12.3, 22q11, and Xp21, and gains at 2p11.1, 3q13.12, 10p11.21, 10q23.1, 11p15, 14q13.2-q13.3, and 17q21.33. In addition, seven CNIs previously implicated as prognostic markers were selected: losses at 8p22 and 16p11.2 and gains at 10p13, 11q13.5, 12p13, 20q13, and Xq28. For all breast cancers combined, the final full model including 19 CNIs, clinical covariates, and tumor marker-approximated subtypes (estrogen receptor [ER], progesterone receptor, ERBB2 amplification, and Ki67) significantly outperformed a model containing only clinical covariates and tumor subtypes (C-Index(full model), train[test]  =  0.72[0.71] ± 0.02 vs. C-Index(clinical + subtype model), train[test]  =  0.62[0.62] ± 0.02; p<10(-6)). In addition, the full model containing 19 CNIs significantly improved prognostication separately for ER-, HER2+, luminal B, and triple negative tumors over clinical variables alone. In summary, we show that a set of 19 CNIs discriminates risk of recurrence among early-stage breast tumors, independent of ER status. Further, our data suggest the presence of specific CNIs that promote and, in some cases, limit tumor spread.

Impact of low estrogen/progesterone receptor expression on survival outcomes in breast cancers previously classified as triple negative breast cancers

PURPOSE

To evaluate the impact of low estrogen/progesterone receptor (ER/PR) expression and effect of endocrine therapy on survival outcomes in human epidermal growth factor receptor 2 (HER2)-negative tumors with ER/PR <10%, previously labeled as triple negative.

METHODS

In a retrospective review, 1257 patients were categorized according their ER/PR percentages into 3 groups, ER/PR <1% (group A), ER/PR 1% to 5% (group B), and ER/PR 6% to 10% (group C). Kaplan-Meier product limit method was used to estimate survival outcomes. Cox proportional hazards models was used to adjust for patient and tumor characteristics.

RESULTS

Groups A, B, and C had 897 (71.4%), 241 (19.2%), and 119 (9.4%) patients, respectively. After a median follow-up of 40 months there was no significant difference in 3-year recurrence-free survival (RFS): 64%, 67%, and 77% (P = .34) or overall survival (OS): 79%, 81%, and 88% (P = .33) for groups A, B, and C, respectively. ER/PR expression was not an independent predictor for RFS (hazard ratio [HR], 1.10; 95% confidence interval [CI], 0.86-1.39; P = .46 for group B, and HR, 0.96; 95% CI, 0.66-1.38; P = .81 for group C, compared with group A), or OS (HR, 1.11; 95% CI, 0.84-1.46; P = .46 for group B, and HR, 0.94; 95% CI, 0.63-1.42; P = .78 for group C, compared with group A). Endocrine therapy had no impact on survival outcomes (RFS: P = .10; OS: P = .45) among groups.

CONCLUSIONS

In this cohort, a low ER/PR level (1%-5%) does not appear to have any significant impact on survival outcomes. There was a tendency for survival advantages in the ER/PR 6% to 10% is seen. Benefit of endocrine therapy in these patients is unclear.

Prognostic significance of tumor grading and staging in mammary carcinomas with neuroendocrine differentiation

Invasive mammary carcinoma with neuroendocrine differentiation has been controversial in terms of its definition and clinical outcome. In 2003, the World Health Organization histologic classification of tumors designated this entity as neuroendocrine carcinoma of the breast and defined mammary neuroendocrine carcinoma as expression of neuroendocrine markers in more than 50% of tumor cells. It is an uncommon neoplasm. Our recent study showed that it is a unique clinicopathologic entity and has a poor clinical outcome compared with invasive mammary carcinoma with similar pathologic stage. Other investigators have also demonstrated a different molecular profile in this type of tumor from that of invasive ductal carcinoma. It is unknown whether the current prognostic markers for invasive mammary carcinoma are also applicable for neuroendocrine carcinoma of the breast. In the current study, we reviewed the clinicopathologic features and outcome data in 74 cases of mammary neuroendocrine carcinoma from the surgical pathology files at The University of Texas, MD Anderson Cancer Center, to identify relevant prognostic markers for this tumor type. As shown previously by univariate analysis, large tumor size, high nuclear grade, and presence of regional lymph node metastasis are adverse prognostic factors for overall survival and distant recurrence-free survival. In the current study, multivariate analysis revealed that overall survival was predicted by tumor size, lymph node status, and proliferation rate as judged by Ki-67 immunohistochemistry. Only nodal status proved to be a significant independent prognostic factor for distant recurrence-free survival. Neither mitosis score nor histologic grade predicted survival in mammary neuroendocrine carcinoma. Our data suggest that routine evaluation of Ki-67 proliferation index in these unusual tumors may provide more valuable information than mitotic count alone.

Age and survival estimates in patients who have node-negative T1ab breast cancer by breast cancer subtype

AIM

This article evaluates the risk of recurrence for patients who have small node-negative breast cancer by age and tumor subtype.

METHODS

One thousand twelve patients with a T1a,bN0 breast cancer diagnosed between 1990 and 2002 who did not receive chemotherapy or trastuzumab were included. Patients and tumor characteristics were compared using the χ(2) or Wilcoxon's rank sum tests. Survival outcomes were estimated with the Kaplan-Meier method and compared using the log-rank statistic. Cox proportional hazards models were used to determine association of breast cancer subtypes and age at diagnosis with other covariates.

RESULTS

Median age was 51.5 years. There were 771 hormone receptor (HR)-positive, 98 HER2-positive, and 143 triple-negative breast cancers (TNBC). Six hundred ninety-three patients were > 50 years, and 33 patients were ≤ 35 years. For 5-year survival estimates, there were 118 deaths and overall survival was 94.6% (95% confidence interval [CI] = 93.2%, 96.1%). After adjusting for breast cancer subtype and other tumor characteristics, patients ≤ 35 had 2.51 (95% CI = 1.21-5.22) times greater risk of worse recurrence-free survival (RFS), and 2.60 (95% CI = 1.05-6.46) times greater risk of worse distant RFS (DRFS) compared to patients > 50 years old. Compared to patients with HR-positive disease, patients with HER2-positive breast cancer had 4.98 (95% CI = 2.91-8.53) times the risk of worse RFS and 4.70 (95% CI = 2.51-8.79) times greater risk of worse DRFS, and patients with TNBC had 2.71 (95% CI = 1.59-4.59) times greater risk of worse RFS and 2.08 (95% CI = 1.04-4.17) times greater risk of worse DRFS.

CONCLUSIONS

In this cohort, patients with T1a,bN0 breast cancer, young age and breast cancer subtype were significantly associated with RFS and DRFS.

Distinct function of androgen receptor coactivator ARA70α and ARA70β in mammary gland development, and in breast cancer

Steroid receptor coactivators are important in regulating the function of the receptors in endocrine organ development and in cancers, including breast. Androgen receptor (AR) coactivator ARA70, was first identified as a gene fused to the ret oncogene and later characterized as an AR coactivator. We previously reported that the full length ARA70α functions as a tumor suppressor gene and that ARA70β functions as an oncogene in prostate cancer. Here we show that both ARA70α and ARA70β function as AR and estrogen receptor (ER) coactivators in breast cancer cells. However, ARA70α and ARA70β serve different functions in mammary gland development and breast cancer tumorigenesis. We observed hypoplastic development of mammary glands in MMTV driven ARA70α transgenic mice and overgrowth of mammary glands in ARA70β transgenic mice at virgin and pregnant stages. We determined that ARA70α inhibited cell proliferation, and that ARA70β promotes proliferation in MCF7 breast cancer cells. These effects were observed in hormone-free media, or in media with androgen or estrogen, though to varying degrees. Additionally, we observed that ARA70β strongly enhanced the invasive ability of MCF7 breast cancer cells in in vitro Matrigel assays. Significantly, decreased ARA70α expression is associated with increased tendency of breast cancer metastasis. In summary, ARA70α and ARA70β have distinct effects in mammary gland development and in the progression of breast cancer.

Abstract LB-379: Combating trastuzumab resistance by targeting Src, a common node downstream of multiple resistance pathways

Objective of the study: Trastuzumab is a highly successful example of rationally designed ERBB2-targeted therapy. However, about half of patients with ERBB2-overexpressing breast cancer do not respond to trastuzumab-based therapies due to various resistance mechanisms. Clinically applicable regimens for overcoming trastuzumab resistance of different mechanisms are not yet available. The objective of the study is to find a common key node of multiple trastuzumab resistance mechanisms and design a clinical applicable strategy to target this common node to more effectively overcome trastuzumab resistance. Methodology: First, we evaluated Src activity in multiple acquired and de novo trastuzumab-resistant cell lines models. Cells with modulated Src activity were examined for trastuzumab resistance in vitro and in an orthotopic xenograft model. Moreover, tumors from patients receiving trastuzumab therapy were also analyzed retrospectively for clinical correlation of Src activity with trastuzumab response. Src activated trastuzumab-resistant cells were further treated with Src inhibitor (saracatinib), trastuzumab, or a combination of both in vitro and in vivo. Results: We demonstrate that the non-receptor tyrosine kinase Src serves as a critical modulator of trastuzumab response and a common node downstream of multiple trastuzumab resistance pathways. Src is activated in both acquired and de novo trastuzumab-resistant cells. Increased Src activation conferred significant trastuzumab resistance (P = 0.011) in breast cancer cells and correlated with trastuzumab resistance in patients. Targeting the common node Src in combination with trastuzumab universally sensitized multiple lines of trastuzumab-resistant cells to trastuzumab and eliminated trastuzumab-resistant tumors in vivo. Targeting Src, a critical convergence point of divergent trastuzumab resistance mechanisms, represents a highly effective and clinically convenient strategy to overcome trastuzumab resistance.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-379. doi:10.1158/1538-7445.AM2011-LB-379

Patients with only 1 positive hormone receptor have increased locoregional recurrence compared with patients with estrogen receptor-positive progesterone receptor-positive disease in very early stage breast cancer

BACKGROUND

Estrogen receptor (ER) and progesterone receptor (PR) are important prognostic and predictive biomarkers in breast cancer. Patients with tumors positive for either receptor are generally considered hormone receptor-positive for treatment decisions. However, some data suggest that patients with ER(+) /PR(-) or ER(-) /PR(+) tumors may have worse outcomes than those with ER(+) /PR(+) tumors. Few data correlate these biomarkers with locoregional (LR) recurrence.

METHODS

The authors retrospectively reviewed records of 635 patients with T1a,bN0 disease who received definitive treatment at their institution between 1997 and 2002 and had archival tissue blocks for prospective assessment of ER/PR expression. They compared clinical outcomes of the 479 patients with ER(+) /PR(+) disease to the 156 patients with ER(+) /PR(-) or ER(-) /PR(+) disease.

RESULTS

LR recurrence rates were higher in patients with 1 receptor positive compared with ER(+) /PR(+) (7-year rate: 8.8% vs 2.5%, P = .024). There was no difference between the 2 groups in the rates of distant metastasis (DM) (P = .531) or overall survival (P = .491). One positive receptor predicted for LR recurrence in patients who did not receive hormonal therapy (P = .046), but not in patients who received hormonal therapy (P = .296). On multivariate analysis, 1 positive receptor predicted for LR recurrence in the overall group (hazard ratio, 2.81; 95% confidence interval, 1.06-7.48; P = .038).

CONCLUSIONS

Patients with T1a,bN0 breast cancer with only 1 positive hormone receptor have increased rates of LR recurrence compared with patients with ER(+) /PR(+) disease, although this difference may be reduced or eliminated with systemic treatment. In contrast, the authors found no evidence of an increased rate of DM in these patients with favorable disease stage.

PI3K pathway mutations and PTEN levels in primary and metastatic breast cancer

The purpose of this work was to determine whether there are differences in PIK3CA mutation status and PTEN protein expression between primary and matched metastatic breast tumors as this could influence patient management. Paraffin sections of 50 μm were used for DNA extraction and slides of 3 μm for immunohistochemistry (IHC) and FISH. Estrogen receptor, progesterone receptor, and HER2 IHC were repeated in a central laboratory for both primary tumors and metastases. PTEN levels were assessed by IHC and phosphoinositide 3-kinase (PI3K) pathway mutations were detected by a mass spectroscopy-based approach. Median age was 48 years (range: 30-83 years). Tumor subtype included 72% hormone receptor positive/HER2 negative, 20% HER2-positive, and less than 7.8% triple receptor negative. Tissues were available for PTEN IHC in 46 primary tumors and 52 metastases. PTEN was lost in 14 (30%) primary tumors and 13 (25%) metastases. There were five cases of PTEN loss and eight cases of PTEN gain from primary tumors to metastases (26% discordance). Adequate DNA was obtained from 46 primary tumors and from 50 metastases for PIK3CA analysis. PIK3CA mutations were detected in 19 (40%) of primary tumors and 21 (42%) of metastases. There were five cases of PIK3CA mutation loss and four cases of mutation gain (18% discordance). There was an increase of the level of PIK3CA mutations in four cases and decrease in one case from primary tumors to metastases. There is a high level of discordance in PTEN level, PIK3CA mutations, and receptor status between primary tumors and metastases that may influence patient selection and response to PI3K-targeted therapies.

Aberrations in pseudoautosomal regions (PARs) found in infertile men with Y-chromosome microdeletions

CONTEXT

The pseudoautosomal regions (PARs) of the Y-chromosome undergo meiotic recombination with the X-chromosome. PAR mutations are associated with infertility and mental and stature disorders.

OBJECTIVE

The aim of the study was to determine whether men with Y-chromosome microdeletions have structural defects in PARs.

DESIGN AND PARTICIPANTS

Eighty-seven infertile men with Y-chromosome microdeletions and 35 controls were evaluated for chromosomal rearrangements using commercial or custom (X- and Y-chromosome) array comparative genomic hybridization or by quantitative PCR of selected PAR genes. Multisoftware-defined chromosomal gains or losses were validated by quantitative PCR and FISH.

RESULTS

Array comparative genomic hybridization confirmed the AZF deletions identified by multiplex PCR. All men with Y-chromosome microdeletions and an abnormal karyotype displayed PAR abnormalities, as did 10% of men with Y-chromosome microdeletions and a normal karyotype. None of the control subjects or infertile men without Y-chromosome microdeletions had PAR duplications or deletions. SHOX aberrations occurred in 14 men (nine gains and five losses); four were short in stature (<10th percentile), and one was tall (>95th percentile). In contrast, the height of 23 men with Y-chromosome microdeletions and normal PARs was average at 176.8 cm (50th percentile).

CONCLUSIONS

Y-chromosome microdeletions can include PAR defects causing genomic disorders such as SHOX, which may be transmitted to offspring. Previously unrecognized PAR gains and losses in men with Y-chromosome microdeletions may have consequences for offspring.

Subunit 6 of the COP9 signalosome promotes tumorigenesis in mice through stabilization of MDM2 and is upregulated in human cancers

The mammalian constitutive photomorphogenesis 9 (COP9) signalosome (CSN), a protein complex involved in embryonic development, is implicated in cell cycle regulation and the DNA damage response. Its role in tumor development, however, remains unclear. Here, we have shown that the COP9 subunit 6 (CSN6) gene is amplified in human breast cancer specimens, and the CSN6 protein is upregulated in human breast and thyroid tumors. CSN6 expression positively correlated with expression of murine double minute 2 (MDM2), a potent negative regulator of the p53 tumor suppressor. Expression of CSN6 appeared to prevent MDM2 autoubiquitination at lysine 364, resulting in stabilization of MDM2 and degradation of p53. Mice in which Csn6 was deleted died early in embryogenesis (E7.5). Embryos lacking both Csn6 and p53 survived to later in embryonic development (E10.5), which suggests that loss of p53 could partially rescue the effect of loss of Csn6. Mice heterozygous for Csn6 were sensitized to γ-irradiation-induced, p53-dependent apoptosis in both the thymus and the developing CNS. These mice were also less susceptible than wild-type mice to γ-irradiation-induced tumorigenesis. These results suggest that loss of CSN6 enhances p53-mediated tumor suppression in vivo and that CSN6 plays an important role in regulating DNA damage-associated apoptosis and tumorigenesis through control of the MDM2-p53 signaling pathway.

Paneth cell-like eosinophilic cytoplasmic granules in breast carcinoma

Prominent coarse eosinophilic cytoplasmic granules reminiscent of those in intestinal Paneth cells are rarely identified in breast carcinomas. In the literature, this phenomenon seems to be associated with acinic cell carcinoma of the breast or microglandular adenosis-related lesions. In this study, we report 3 breast carcinoma cases with such granules. Two of the cases were carcinomas arising in microglandular adenosis, one of which contained areas of acinic carcinoma-like features. The other case was a mammary carcinoma with prominent microglandular adenosis and also acinic cell carcinoma growth patterns. In the latter case, the patient had a history of neoadjuvant chemotherapy; and cells with coarse granules were found in both the pretreatment and posttreatment specimens. Although all 3 tumors were negative for HER2/neu, 2 tumors were estrogen receptor/progesterone receptor negative and one was estrogen receptor/progesterone receptor positive. Follow-up for 2 patients at 12 months and 3 years showed no evidence of disease, and the other patient died of her disease at 34 months. We provide a review of the literature and conclude that prominent coarse eosinophilic granules are a rare and nonspecific feature in breast epithelium. The clinical significance remains to be investigated, given the limited experience.

Abstract P3-10-23: Caveolin 1 and Patient Outcomes in Breast Cancer

Introduction: Caveolin 1 (Cav1) protein is a structural component of caveolae in cell membranes and is also present in the cell cytoplasm, nucleus and extracellular milieu. It regulates multiple cellular processes and has been reported to both positively and negatively effect tumour progression. In normal and malignant breast tissue Cav1 is immunohistochemically expressed in myoepithelial and stromal cells but rarely in luminal epithelial or breast cancer cells. Recent reports have correlated Cav1 expression in the stromal tumour microenvironment with lower tumor stage, grade and improved prognosis. This suggests a separate role for Cav 1 in influencing tumour behaviour by regulating the tumour microenvironment. Our aim was to further investigate the role of Cav1 in breast cancer by for the first time analysing its expression by reverse phase protein array(RPPA). Methods: We examined expression levels of Cav1 in 52 breast cancer cell lines and a large human early breast cancer cohort(n=712) with cancer cells composing 70% of the macrodissected breast cancer specimens used. Data was recorded when available for each case on standard clinical, pathological and survival endpoints. We examined the effect of Cav1 expression on tumour biology and patient survival. Results: High levels of Cav1 expression in breast cancer cell lines was strongly correlated with a TN phenotype (P&lt;0.001). Cav 1 expression was more strongly associated with the stromal subtype rather than basal subtype of TN cell lines (p=0.02).

In contrast, in human tumour tissue high levels of Cav1 correlated with the hormone receptor positive(ER) phenotype. There was also an association between Cav 1 expression and lower grade (P&lt;0.001), lower T stage (P&lt;0.001) and lower N stage (P&lt;0.001).

Cav 1 was significantly associated with improved relapse-free (RFS) and overall survival (OS) in the human cohort. On multivariate(MV) analysis Cav1 was associated with OS(HR 0.91/95% CI 0.82-1/p=0.05) but not RFS. In the subset of ER patients who only received adjuvant tamoxifen (n=199) Cav1 was also significantly associated with improved RFS and OS. MV analysis again showed this correlation to remain for OS (HR 0.81/95% CI 0.65-1/p=0.05) but not for RFS. In the TN subset (n=161) Cav1 expression did not have any survival impact. Discussion: Our results show different expression patterns of Cav1 in vitro and in vivo. TN tumors are thought to originate from the myoepithelial or stromal component of breast tissue which may explain the high levels of Cav1 in this subgroup of breast cancer cell lines. On the other hand, human tumour tissue showed an association between high Cav1 levels and ER tumours. Analysis of these macrodissected samples likely included stromal tissue surrounding the epithelial tumour cells which may explain this discrepancy.

Our data also show a correlation between high in vivo levels of Cav1 and less aggressive tumours with improved prognosis. On MV analysis Cav1 was an independent predictor of outcome in the whole cohort and in the ER subset treated with adjuvant tamoxifen only. Expression of stromal Cav1 measured by RPPA may again partly explain these findings. Further analysis with fully microdissected human breast tissue and immunohistochemical analysis of both stromal and cancer cell Cav1 expression is planned.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-23.

Abstract P3-10-41: Quantitative Immunohistochemical Analysis and Prognostic Significance of TRPS-1, a New GATA Transcription Factor Family Member, in Breast Cancer

The Trichorhinophalangeal Syndrome-1 gene (TRPS-1) is a novel GATA transcription factor family member expressed in &gt;90% of human breast cancers. In this study, we developed a new quantitative IHC (qIHC) method to study TRPS-1 as a possible indicator ofprognosis in BC. Using this method, a quantitative parameter for TRPS-1 expression called a Quick Score (QS) was derived from the measured Labeling Index (LI) and Mean Optical Density (MOD) after IHC and applied to a set of 152 Stage II/III BC patients from 1993-2006 who did not receive preoperative chemotherapy. Although highly prevalent in BC, a wide range of TRPS-1 QS was found among the sample set with higher TRPS-1 QS significantly associated with tumor ER-alpha (p= 0.023 for QS, and p= 0.028 for Allred score), PR (p= 0.009), GATA-3 (P&lt;0.0001), and E-cadherin (p&lt; 0.001). TRPS-1 QS was also positively associated with HER2 status (p=0.026). Analysis of different ductal structures revealed that TRPS-1 was expressed at low levels in normal ducts and in usual ductal hyperplasia, but showed a marked increase in DCIS and invasive carcinoma lesions. An analysis of TRPS-1 expression in association with overall survival revealed that TRPS-1 QS (≥4.0) was significantly associated with improved survival (p=0.0165). Patients with TRPS-1 QS &lt;4 had a hazard ratio of 2 (p=0.019) after univariate Cox proportional hazards analysis. Further analysis of the patient samples revealed an ER-/lo, HER2+ (amplified) BC subset in which TRPS-1 expression above a critical quantitative threshold was predictive of greatly improved survival (median survival not reached after 10 years), while patients in this subset with TRPS-1 expression below this threshold having a median survival of less than 5 years. In summary, this new qIHC approach revealed critical differences in TRPS-1 expression in primary BC samples and found that this new GATA family member may be a promising positive prognostic marker that may regulate BC progression. In addition, TRPS-1 may also be a relevant new marker in a luminal ER-/low, HER2+ BC subset.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-41.

Quantitative immunohistochemical analysis and prognostic significance of TRPS-1, a new GATA transcription factor family member, in breast cancer

The trichorhinophalangeal syndrome 1 (TRPS-1) gene is a novel GATA transcription factor family member. Previously, using a gene expression profiling and immunohistochemistry (IHC) screen, we identified TRPS-1 as a highly prevalent gene in breast cancer (BC), expressed in >90% of estrogen receptor alpha (ERα)(+) and ERα(-) BC subtypes. TRPS-1 was also shown to be expressed in prostate cancer where it was shown to play a proapoptotic function during androgen withdrawal possibly through regulating antioxidant metabolism. The role of TRPS-1 and its prognostic significance in hormone-dependent and hormone-independent BC however is not known. In this study, we developed a new quantitative IHC (qIHC) method to further study TRPS-1 as a marker and possible prognostic indicator in BC. By using this method, a quantitative parameter for TRPS-1 expression called a quick score (QS) was derived from the measured labeling index and mean optical density after IHC and applied to a set of 152 stage II/III BC patients from 1993 to 2006 who did not receive preoperative chemotherapy. Associations between QS and tumor characteristics were evaluated using the Kruskal-Wallis test. A wide range of TRPS-1 QS was found among the sample set with higher TRPS-1 QS significantly associated with tumor ERα (p = 0.023 for QS and p = 0.028 for Allred score), progesterone receptor (p = 0.009), and GATA-3 (p < 0.0001). TRPS-1 QS was also positively associated with HER2 status (p = 0.026). Further analysis of different ductal structures in ten BC cases revealed that TRPS-1 expression was expressed at low levels in the remaining normal ducts and in areas of usual ductal hyperplasia but showed marked increase in expression in ductal carcinoma in situ and invasive carcinoma lesions in the tissue. An analysis of TRPS-1 expression in association with overall survival in the 152 stage II/III sample set also revealed that TRPS-1 QS (≥4.0) was significantly associated with improved survival (p = 0.0165). Patients with TRPS-1 QS <4 had a hazard ratio of 2 (p = 0.019) after univariate Cox proportional hazards analysis. In summary, this new qIHC approach was found to reveal critical differences in TRPS-1 expression in primary BC samples and found that it is a promising prognostic marker that should be further evaluated as a possible tumor suppressor gene facilitating improved survival in different subtypes of BC.

Clinicopathologic factors associated with involved margins after breast-conserving surgery for invasive lobular carcinoma

INTRODUCTION

Obtaining negative margins for patients undergoing breast-conserving surgery (BCS) for invasive lobular carcinoma (ILC) can be difficult because of the unique histologic pattern of ILC. Our goal was to determine whether any specific patient- or disease-related factors influenced margin status.

PATIENTS AND METHODS

We retrospectively reviewed 211 patients with ILC treated from 1994 through 2004 to determine if specific clinical and pathologic factors influenced the ability to obtain negative margins.

RESULTS

We identified 110 patients (52%) who underwent total mastectomy and 101 (48%) who underwent BCS. Among patients who underwent BCS, 50 (50%) had close or positive margins. Patients with close or positive margins were more likely to have architectural distortion on ultrasonography (vs. mass or calcifications; P = .049), to have undergone excisional biopsy (vs. core or fine-needle aspiration; P = .008), and to have associated ductal carcinoma in situ (P = .021). On multivariate analysis, only biopsy method retained significance (P = .006).

CONCLUSION

Core needle biopsy is the preferred method of diagnostic biopsy before surgical intervention. With appropriate patient selection, most patients with early-stage ILC can undergo successful BCS.