Outcome without any adjuvant systemic treatment in stage I ER+/HER2- breast cancer patients included in the MINDACT trial.

BACKGROUND: Adjuvant systemic treatments (AST) reduce mortality, but have associated short- and long-term toxicities. Careful selection of patients likely to benefit from AST is needed. We evaluated outcome of low-risk breast cancer patients of the EORTC 10041/BIG 3-04 MINDACT trial who received no AST. PATIENTS AND METHODS: Patients with estrogen receptor-positive, HER2-negative, lymph node-negative tumors ≤2 cm who received no AST were matched 1 : 1 to patients with similar tumor characteristics treated with adjuvant endocrine therapy (ET), using propensity score matching and exact matching on age, genomic risk (70-gene signature) and grade. In a post hoc analysis, distant metastasis-free interval (DMFI) and overall survival (OS) were assessed by Kaplan-Meier analysis and hazard ratios (HR) by Cox regression. Cumulative incidences of locoregional recurrence (LRR) and contralateral breast cancer (CBC) were assessed with competing risk analyses. RESULTS: At 8 years, DMFI rates were 94.8% [95% confidence interval (CI) 92.7% to 96.9%] in 509 patients receiving no AST, and 97.3% (95% CI 95.8% to 98.8%) in 509 matched patients who received only ET [absolute difference: 2.5%, HR 0.56 (95% CI 0.30-1.03)]. No statistically significant difference was seen in 8-year OS rates, 95.4% (95% CI 93.5% to 97.4%) in patients receiving no AST and 95.6% (95% CI 93.8% to 97.5%) in patients receiving only ET [absolute difference: 0.2%, HR 0.86 (95% CI 0.53-1.41)]. Cumulative incidence rates of LRR and CBC were 4.7% (95% CI 3.0% to 7.0%) and 4.6% (95% CI 2.9% to 6.9%) in patients receiving no AST versus 1.4% (95% CI 0.6% to 2.9%) and 1.5% (95% CI 0.6% to 3.1%) in patients receiving only ET. CONCLUSIONS: In patients with stage I low-risk breast cancer, the effect of ET on DMFI was limited, but overall significantly fewer breast cancer events were observed in patients who received ET, after the relatively short follow-up of 8 years. These benefits and side-effects of ET should be discussed with all patients, even those at a very low risk of distant metastasis.

Combining method of detection and 70-gene signature for enhanced prognostication of breast cancer.

PURPOSE: Studies have shown that screen detection by national screening programs is independently associated with better prognosis of breast cancer. The aim of this study is to evaluate the association between tumor biology according to the 70-gene signature (70-GS) and survival of patients with screen-detected and interval breast cancers. METHODS: All Dutch breast cancer patients enrolled in the MINDACT trial (EORTC-10041/BIG3-04) accrued 2007-2011, who participated in the national screening program (biennial screening, ages 50-75) were included (n = 1102). Distant Metastasis-Free Interval (DMFI) was evaluated according to the 70-GS for patients with screen-detected (n = 754) and interval cancers (n = 348). RESULTS: Patients with screen-detected cancers had 8-year DMFI rates of 98.2% for 70-GS ultralow-, 94.6% for low-, and 93.8% for high-risk tumors (p = 0.4). For interval cancers, there was a significantly lower 8-year DMFI rate for patients with 70-GS high-risk tumors (85.2%) compared to low- (92.2%) and ultralow-risk tumors (97.4%, p = 0.0023). Among patients with 70-GS high-risk tumors, a significant difference in 8-year DMFI rate was observed between interval (85.2%, n = 166) versus screen-detected cancers (93.8%, n = 238; p = 0.002) with a HR of 2.3 (95%CI 1.2-4.4, p = 0.010) adjusted for clinical-pathological characteristics and adjuvant systemic treatment. CONCLUSION: Among patients with 70-GS high-risk tumors, a significant difference in DMFI was observed between screen-detected and interval cancers, suggesting that method of detection is an additional prognostic factor in this subgroup and should be taken into account when deciding on adjuvant treatment strategies.

Enrichment of high-grade tumors in breast cancer gene expression studies.

PURPOSE: Gene expression (GE) profiling for breast cancer classification and prognostication has become increasingly used in clinical diagnostics. GE profiling requires a reasonable tumor cell percentage and high-quality RNA. As a consequence, a certain amount of samples drop out. If tumor characteristics are different between samples included and excluded from GE profiling, this can lead to bias. Therefore, we assessed whether patient and tumor characteristics differ between tumors suitable or unsuitable for generating GE profiles in breast cancer. METHODS: In a consecutive cohort of 738 breast cancer patients who received neoadjuvant chemotherapy at the Netherlands Cancer Institute, GE profiling was performed. We compared tumor characteristics and treatment outcome between patients included and excluded from GE profiling. Results were validated in an independent cohort of 812 patients treated with primary surgery. RESULTS: GE analysis could be performed in 53% of the samples. Patients with tumor GE profiles more often had high-grade tumors [odds ratio 2.57 (95%CI 1.77-3.72), p < 0.001] and were more often lymph node positive [odds ratio 1.50 (95%CI 1.03-2.19), p = 0.035] compared to the group for which GE profiling was not possible. In the validation cohort, tumors suitable for gene expression analysis were more often high grade. CONCLUSIONS: In our gene expression studies, tumors suitable for GE profiling had more often an unfavorable prognostic profile. Due to selection of samples with a high tumor percentage, we automatically select for tumors with specific features, i.e., tumors with a higher grade and lymph node involvement. It is important to be aware of this phenomenon when performing gene expression analysis in a research or clinical context.

An association study of established breast cancer reproductive and lifestyle risk factors with tumour subtype defined by the prognostic 70-gene expression signature (MammaPrint®).

BACKGROUND: Reproductive and lifestyle factors influence both breast cancer risk and prognosis; this might be through breast cancer subtype. Subtypes defined by immunohistochemical hormone receptor markers and gene expression signatures are used to predict prognosis of breast cancer patients based on their tumour biology. We investigated the association between established breast cancer risk factors and the 70-gene prognostication signature in breast cancer patients. PATIENTS AND METHODS: Standardised questionnaires were used to obtain information on established risk factors of breast cancer from the Dutch patients of the MINDACT trial. Clinical-pathological and genomic information were obtained from the trial database. Logistic regression analyses were used to estimate the associations between lifestyle risk factors and tumour prognostic subtypes, measured by the 70-gene MammaPrint® signature (i.e. low-risk or high-risk tumours). RESULTS: Of the 1555 breast cancer patients included, 910 had low-risk and 645 had high-risk tumours. Current body mass index (BMI), age at menarche, age at first birth, age at menopause, hormonal contraceptive use and hormone replacement therapy use were not associated with MammaPrint®. In parous women, higher parity was associated with a lower risk (OR: 0.75, [95% confidence interval {CI}: 0.59-0.95] P = 0.018) and longer breastfeeding duration with a higher risk (OR: 1.03, [95% CI: 1.01-1.05] P = 0.005) of developing high-risk tumours; risk estimates were similar within oestrogen receptor-positive disease. After stratifying by menopausal status, the associations remained present in post-menopausal women. CONCLUSION: Using prognostic gene expression profiles, we have indications that specific reproductive factors may be associated with prognostic tumour subtypes beyond hormone receptor status.

Changes over time in the impact of gene-expression profiles on the administration of adjuvant chemotherapy in estrogen receptor positive early stage breast cancer patients: A nationwide study.

Ten years ago gene-expression profiles were introduced to aid adjuvant chemotherapy decision making in breast cancer. Since then subsequent national guidelines gradually expanded the indication area for adjuvant chemotherapy. In this nation-wide study the evolution of the proportion of patients with estrogen-receptor positive (ER+) tumors receiving adjuvant chemotherapy in relation to gene-expression profile use in patient groups that became newly eligible for chemotherapy according to national guideline changes over time is assessed. Data on all surgically treated early breast cancer patients diagnosed between 2004-2006 and 2012-2014 were obtained from the Netherlands Cancer Registry. ER+/Her2- patients with tumor-characteristics making them eligible for gene-expression testing in both cohorts and a discordant chemotherapy recommendation over time (2004 guideline not recommending and 2012 guideline recommending chemotherapy) were identified. We identified 3,864 patients eligible for gene-expression profile use during both periods. Gene-expression profiles were deployed in 5% and 35% of the patients in the respective periods. In both periods the majority of patients was assigned to a low genomic risk-profile (67% and 69%, respectively) and high adherence rates to the test result were observed (86% and 91%, respectively). Without deploying a gene-expression profile 8% and 52% (p <0.001) of the respective cohorts received chemotherapy while 21% and 28% of these patients received chemotherapy when a gene-expression profile was used (p 0.191). In conclusion, in ER+/Her2- early stage breast cancer patients gene-expression profile use was associated with a consistent proportion of patients receiving chemotherapy despite an adjusted guideline-based recommendation to administer chemotherapy.

Using a gene expression signature when controversy exists regarding the indication for adjuvant systemic treatment reduces the proportion of patients receiving adjuvant chemotherapy: a nationwide study.

PURPOSE: The Dutch national guideline advises use of gene-expression signatures, such as the 70-gene signature (70-GS), in case of ambivalence regarding the benefit of adjuvant chemotherapy (CT). In this nationwide study, the impact of 70-GS use on the administration of CT in early breast cancer patients with a dubious indication for CT is assessed. METHODS: Patients within a national guideline directed indication area for 70-GS use who were surgically treated between November 2011 and April 2013 were selected from the Netherlands Cancer Registry database. The effect of 70-GS use on the administration of CT was evaluated in guideline- and age-delineated subgroups addressing potential effect of bias by linear mixed-effect modeling and instrumental variable (IV) analyses. RESULTS: A total of 2,043 patients within the indicated area for 70-GS use were included, of whom 298 received a 70-GS. Without use of the 70-GS, 45% of patients received CT. The 70-GS use was associated with a 9.5% decrease in CT administration (95% confidence interval (CI): -15.7 to -3.3%) in linear mixed-effect model analyses and IV analyses showed similar results (-9.9%; 95% CI: -19.3 to -0.4). CONCLUSION: In patients in whom the Dutch national guidelines suggest the use of a gene-expression profile, 70-GS use is associated with a 10% decrease in the administration of adjuvant CT.Genet Med 18 7, 720-726.Genetics in Medicine (2016); 18 7, 720-726. doi:10.1038/gim.2015.152.

Gene expression profiling to predict the risk of locoregional recurrence in breast cancer: a pooled analysis.

The 70-gene signature (MammaPrint) has been developed to predict the risk of distant metastases in breast cancer and select those patients who may benefit from adjuvant treatment. Given the strong association between locoregional and distant recurrence, we hypothesize that the 70-gene signature will also be able to predict the risk of locoregional recurrence (LRR). 1,053 breast cancer patients primarily treated with breast-conserving treatment or mastectomy at the Netherlands Cancer Institute between 1984 and 2006 were included. Adjuvant treatment consisted of radiotherapy, chemotherapy, and/or endocrine therapy as indicated by guidelines used at the time. All patients were included in various 70-gene signature validation studies. After a median follow-up of 8.96 years with 87 LRRs, patients with a high-risk 70-gene signature (n = 492) had an LRR risk of 12.6% (95% CI 9.7-15.8) at 10 years, compared to 6.1% (95% CI 4.1-8.5) for low-risk patients (n = 561; P < 0.001). Adjusting the 70-gene signature in a competing risk model for the clinicopathological factors such as age, tumour size, grade, hormone receptor status, LVI, axillary lymph node involvement, surgical treatment, endocrine treatment, and chemotherapy resulted in a multivariable HR of 1.73 (95% CI 1.02-2.93; P = 0.042). Adding the signature to the model based on clinicopathological factors improved the discrimination, albeit non-significantly [C-index through 10 years changed from 0.731 (95% CI 0.682-0.782) to 0.741 (95% CI 0.693-0.790)]. Calibration of the prognostic models was excellent. The 70-gene signature is an independent prognostic factor for LRR. A significantly lower local recurrence risk was seen in patients with a low-risk 70-gene signature compared to those with high-risk 70-gene signature.

Optimized outcome prediction in breast cancer by combining the 70-gene signature with clinical risk prediction algorithms.

Clinical guidelines for breast cancer treatment differ in their selection of patients at a high risk of recurrence who are eligible to receive adjuvant systemic treatment (AST). The 70-gene signature is a molecular tool to better guide AST decisions. The aim of this study was to evaluate whether adding the 70-gene signature to clinical risk prediction algorithms can optimize outcome prediction and consequently treatment decisions in early stage, node-negative breast cancer patients. A 70-gene signature was available for 427 patients participating in the RASTER study (cT1-3N0M0). Median follow-up was 61.6 months. Based on 5-year distant-recurrence free interval (DRFI) probabilities survival areas under the curve (AUC) were calculated and compared for risk estimations based on the six clinical risk prediction algorithms: Adjuvant! Online (AOL), Nottingham Prognostic Index (NPI), St. Gallen (2003), the Dutch National guidelines (CBO 2004 and NABON 2012), and PREDICT plus. Also, survival AUC were calculated after adding the 70-gene signature to these clinical risk estimations. Systemically untreated patients with a high clinical risk estimation but a low risk 70-gene signature had an excellent 5-year DRFI varying between 97.1 and 100 %, depending on the clinical risk prediction algorithms used in the comparison. The best risk estimation was obtained in this cohort by adding the 70-gene signature to CBO 2012 (AUC: 0.644) and PREDICT (AUC: 0.662). Clinical risk estimations by all clinical algorithms improved by adding the 70-gene signature. Patients with a low risk 70-gene signature have an excellent survival, independent of their clinical risk estimation. Adding the 70-gene signature to clinical risk prediction algorithms improves risk estimations and therefore might improve the identification of early stage node-negative breast cancer patients for whom AST has limited value. In this cohort, the PREDICT plus tool in combination with the 70-gene signature provided the best risk prediction.

Risk estimations and treatment decisions in early stage breast cancer: agreement among oncologists and the impact of the 70-gene signature.

BACKGROUND: Clinical decision-making in patients with early stage breast cancer requires adequate risk estimation by medical oncologists. This survey evaluates the agreement among oncologists on risk estimations and adjuvant systemic treatment (AST) decisions and the impact of adding the 70-gene signature to known clinico-pathological factors. METHODS: Twelve medical oncologists assessed 37 breast cancer cases (cT1-3N0M0) and estimated their risk of recurrence (high or low) and gave a recommendation for AST. Cases were presented in two written questionnaires sent 4 weeks apart. Only the second questionnaire included the 70-gene signature result. RESULTS: The level of agreement among oncologists in risk estimation (κ=0.57) and AST recommendation (κ=0.57) was 'moderate' in the first questionnaire. Adding the 70-gene signature result significantly increased the agreement in risk estimation to 'substantial' (κ=0.61), while agreement in AST recommendations remained 'moderate' (κ=0.56). Overall, the proportion of high risk was reduced with 7.4% (range: 6.9-22.9%; p<0.001) and the proportion of chemotherapy that was recommended was reduced with 12.2% (range: 5.4-29.5%; p<0.001). CONCLUSION: Oncologists' risk estimations and AST recommendations vary greatly. Even though the number of participating oncologists is low, our results underline the need for a better standardisation tool in clinical decision-making, in which integration of the 70-gene signature may be helpful in certain subgroups to provide patients with individualised, but standardised treatment.

Mammographic screening detects low-risk tumor biology breast cancers.

Overdiagnosis of breast cancer, i.e. the detection of slow-growing tumors that would never have caused symptoms or death, became more prevalent with the implementation of population-based screening. Only rough estimates have been made of the proportion of patients that are overdiagnosed and identification of those patients is difficult. Therefore, the aim of this study is to evaluate whether tumor biology can help identify patients with screen-detected tumors at such a low risk of recurrence that they are likely to be overdiagnosed. Furthermore, we wish to evaluate the impact of the transition from film-screen mammography (FSM) to the more sensitive full-field digital mammography (FFDM) on the biology of the tumors detected by each screening-modality. All Dutch breast cancer patients enrolled in the MINDACT trial (EORTC-10041) accrued 2007-2011, who participated in the national screening program (biennial screening ages 50-75) were included (n = 1,165). We calculated the proportions of high-, low- and among those the ultralow-risk tumors according to the 70-gene signature for patients with screen-detected (n = 775) and interval (n = 390) cancers for FSM and FFDM. Screen-detected cancers had significantly more often a low-risk tumor biology (68 %) of which 54 % even an ultralow-risk compared to interval cancers (53 % low-, of which 45 % ultralow-risk (p = 0.001) with an OR of 2.33 (p < 0.0001; 95 % CI 1.73-3.15). FFDM detected significantly more high-risk tumors (35 %) compared to FSM (27 %) (p = 0.011). Aside from favorable clinico-pathological factors, screen-detected cancers were also more likely to have a biologically low-risk or even ultralow-risk tumor. Especially for patients with screen-detected cancers the use of tools, such as the 70-gene signature, to differentiate breast cancers by risk of recurrence may minimize overtreatment. The recent transition in screening-modalities led to an increase in the detection of biologically high-risk cancers using FFDM.

Long-term impact of the 70-gene signature on breast cancer outcome.

Several studies have validated the prognostic value of the 70-gene prognosis signature (MammaPrint(R)), but long-term outcome prediction of these patients has not been previously reported. The follow-up of the consecutively treated cohort of 295 patients (<53 years) with invasive breast cancer (T1-2N0-1M0; n = 151 N0, n = 144 N1) diagnosed between 1984 and 1995, in which the 70-gene signature was previously validated, was updated. The median follow-up for this series is now extended to 18.5 years. A significant difference is seen in long-term distant metastasis-free survival (DMFS) for the patients with a low- and a high-risk 70-gene signature (DMFS p < 0.0001), as well as separately for node-negative (DMFS p < 0.0001) and node-positive patients (DMFS p = 0.0004). The 25-year hazard ratios (HRs) for all patients for DMFS and OS were 3.1 (95 % CI 2.02-4.86) and 2.9 (95 % CI 1.90-4.28), respectively. The HRs for DMFS and OS were largest in the first 5 years after diagnosis: 9.6 (95 % CI 4.2-22.1) and 11.3 (95 % CI 3.5-36.4), respectively. The 25-year HRs in the subgroup of node-negative patients for DMFS and OS were 4.57 (95 % CI 2.31-9.04) and 4.73 (95 % CI 2.46-9.07), respectively, and for node-positive patients for DMFS and OS were 2.24 (95 % CI 1.25-4.00) and 1.83 (95 % CI 1.07-3.11), respectively. The 70-gene signature remains prognostic at longer follow-up in patients <53 years of age with stage I and II breast cancer. The 70-gene signature's strongest prognostic power is seen in the first 5 years after diagnosis.

Prospective cost-effectiveness analysis of genomic profiling in breast cancer.

BACKGROUND: The cost-effectiveness of the 70-gene signature (70-GS) (MammaPrint®) has earlier been estimated using retrospective validation data. Based on the prospective 5-year survival data of the microarRAy-prognoSTics-in-breast-cancER (RASTER) study, the aim here was to evaluate the cost-effectiveness reflecting the actual use in clinical practice, including reality-based compliance rates. METHODS: Costs and outcomes (quality-adjusted-life-years (QALYs)) were calculated in node-negative (N-) patients included in the RASTER study (n=427). Sensitivity and specificity of the 70-gene and Adjuvant! Online (AO) were based on 5-year distant-disease-free survival (DDFS). Subgroup analyses were performed for two groups for whom benefit of the 70-gene had earlier been reported: (1) ductal, oestrogen receptor-positive (ER+), tumour diameter 10-30 mm, grade II, age 40-70; (2) ductal, oestrogen receptor-positive, tumour diameter 5-30 mm, grade II/III and age 40-70. RESULTS: Based on 5-year survival data, the cost-effectiveness of the 70-gene signature versus AO was prospectively confirmed. The total health care costs per patient were €26,786 for the 70-gene and €29,187 for AO. The quality adjusted life years yielded 12.49 and 11.88, respectively. The subgroups retrieved slightly higher life gains and higher costs, but all resulted finally in a favourable position for the 70-gene signature. CONCLUSIONS: The use of the 70-gene signature, as judged appropriate by doctors and patients and supported by a low risk 70-gene signature as an oncological safe choice, was also found to be cost-effective.

A prospective evaluation of a breast cancer prognosis signature in the observational RASTER study.

The 70-gene signature (MammaPrint™) has been developed on retrospective series of breast cancer patients to predict the risk of breast cancer distant metastases. The microarRAy-prognoSTics-in-breast-cancER (RASTER) study was the first study designed to prospectively evaluate the performance of the 70-gene signature, which result was available for 427 patients (cT1-3N0M0). Adjuvant systemic treatment decisions were based on the Dutch CBO 2004 guidelines, the 70-gene signature and doctors' and patients' preferences. Five-year distant-recurrence-free-interval (DRFI) probabilities were compared between subgroups based on the 70-gene signature and Adjuvant! Online (AOL) (10-year survival probability <90% was defined as high-risk). Median follow-up was 61.6 months. Fifteen percent (33/219) of the 70-gene signature low-risk patients received adjuvant chemotherapy (ACT) versus 81% (169/208) of the 70-gene signature high-risk patients. The 5-year DRFI probabilities for 70-gene signature low-risk (n = 219) and high-risk (n = 208) patients were 97.0% and 91.7%. The 5-year DRFI probabilities for AOL low-risk (n = 132) and high-risk (n = 295) patients were 96.7% and 93.4%. For 70-gene signature low-risk-AOL high-risk patients (n = 124), of whom 76% (n = 94) had not received ACT, 5-year DRFI was 98.4%. In the AOL high-risk group, 32% (94/295) less patients would be eligible to receive ACT if the 70-gene signature was used. In this prospective community-based observational study, the 5-year DRFI probabilities confirmed the additional prognostic value of the 70-gene signature to clinicopathological risk estimations such as AOL. Omission of adjuvant chemotherapy as judged appropriate by doctors and patients and instigated by a low-risk 70-gene signature result, appeared not to compromise outcome.

Paraneoplastic gastro-intestinal anti-Hu syndrome in neuroblastoma.

The anti-Hu syndrome is a well-known paraneoplastic syndrome and may be rarely seen in patients with neuroblastoma. However, it is relatively unknown that anti-Hu antibodies can cause gastro-intestinal signs and symptoms. We report on a child with neuroblastoma who presented with gastro-intestinal disturbances as a result of the anti-Hu syndrome and summaries two similar case reports reported in literature. Neuroblastoma patients with gastro-intestinal disturbances, ranging from constipation to a paralytic ileus, might suffer from the gastro-intestinal anti-Hu syndrome. The causative antibodies can be determined to diagnose or exclude this syndrome, and successful treatment is possible.