Abstract PD07-06: NEO-ZOTAC: Toxicity data of a phase III randomized trial with NEOadjuvant chemotherapy (TAC) with or without ZOledronic acid (ZA) for patients with HER2-negative large resectable or locally advanced breast cancer (BC)

Background: The role of bisphosphonates (BP) when added to the (neo)adjuvant treatment of BC in enhancing the efficacy of therapy is still unknown. NEOZOTAC investigates the efficacy of ZA added to neoadjuvant chemotherapy in patients with HER2-negative BC.

Trial design: NEOZOTAC is a Dutch multicenter study. Patients are 1:1 randomized to 3-weekly TAC (docetaxel 75mg/m2, adriamycin 50 mg/m2 and cyclophosphamide 500 mg/m2 i.v., day 1) chemotherapy supported by pegfilgrastim (6 mg sc), day 2 with or without ZA (4 mg i.v. within 24 hr after chemotherapy) q3 weeks.

Eligibility criteria: Main inclusion criteria: stage II or III, measurable, HER2-negative BC, age ≥18 years, WHO 0–2, adequate bone marrow-, renal-, and liver function, absence of prior BP usage and absence of active dental problems.

Study endpoint: The primary endpoint is the pathologic complete response (pCR) rate. Secondary endpoints are toxicity, clinical response, tumor heterogeneity in core biopsy vs. operation specimen, and (disease free) survival. Optional side studies include fluorescent imaging (SoftScan®), changes in bone markers, single nucleotide polymorphisms and the insulin-like growth factor pathway, circulating tumor and endothelial cells and the false-negative rate of the sentinel node biopsy after neoadjuvant chemotherapy.

Statistical Methods: Using a 5% significance level based on the two-sided Fishers exact test with a power of 80%, 250 patients (125/arm) are needed to show an improvement of the pCR-rate from 17% to 34% in the experimental arm. Randomization was done according to the Pococks minimisation technique stratified by cT, cN, and estrogen receptor status. Toxicity is analyzed using the Exact (2-sided) Chi-Square test.

Results: From July 2010 to April 2012, 250 patients from 25 participating sites were randomized. Toxicity data of 173 patients are currently available and data of all 250 patients will be presented at SABCS. Patient characteristics are presented in table 1.

Relationship between specific adverse events and efficacy of exemestane therapy in early postmenopausal breast cancer patients

BACKGROUND

Many adverse events (AEs) associated with aromatase inhibitors (AIs) involve symptoms related to the depletion of circulating estrogens, and may be related to efficacy. We assessed the relationship between specific AEs [hot flashes (HF) and musculoskeletal AEs (MSAE)] and survival outcomes in Dutch and Belgian patients treated with exemestane (EXE) in the Tamoxifen Exemestane Adjuvant Multinational (TEAM) trial. Additionally, the relationship between hormone receptor expression and AEs was assessed.

METHODS

Efficacy end points were relapse-free survival (RFS), overall survival (OS) and breast cancer-specific mortality (BCSM), starting at 6 months after starting EXE treatment. AEs reported in the first 6 months of treatment were included. Specific AEs comprised HF and/or MSAE. Landmark analyses and Cox proportional hazards models assessed survival differences up to 5 years.

RESULTS

A total of 1485 EXE patients were included. Patients with HF had a better RFS than patients without HF [multivariate hazard ratio (HR) 0.393, 95% confidence interval (CI) 0.19-0.813; P = 0.012]. The occurrence of MSAE versus no MSAE did not relate to better RFS (multivariate HR 0.677, 95% CI 0.392-1.169; P = 0.162). Trends were maintained for OS and BCSM. Quantitative hormone receptor expression was not associated with specific AEs.

CONCLUSIONS

Some AEs associated with estrogen depletion are related to better outcomes and may be valuable biomarkers in AI treatment.

Differences in outcomes of oesophageal and gastric cancer surgery across Europe

BACKGROUND

In several European countries, centralization of oesophagogastric cancer surgery has been realized and clinical audits initiated. The present study was designed to evaluate differences in resection rates, outcomes and annual hospital volumes between these countries, and to analyse the relationship between hospital volume and outcomes.

METHODS

National data were obtained from cancer registries or clinical audits in the Netherlands, Sweden, Denmark and England. Differences in outcomes were analysed between countries and between hospital volume categories, adjusting for available case-mix factors.

RESULTS

Between 2004 and 2009, 10 854 oesophagectomies and 9010 gastrectomies were registered. Resection rates in England were 18·2 and 21·6 per cent for oesophageal and gastric cancer respectively, compared with 28·5-29·9 and 41·4-41·9 per cent in the Netherlands and Denmark (P < 0·001). The adjusted 30-day mortality rate after oesophagectomy was lowest in Sweden (1·9 per cent). After gastrectomy, the adjusted 30-day mortality rate was significantly higher in the Netherlands (6·9 per cent) than in Sweden (3·5 per cent; P = 0·017) and Denmark (4·3 per cent; P = 0·029). Increasing hospital volume was associated with a lower 30-day mortality rate after oesophagectomy (odds ratio 0·55 (95 per cent confidence interval 0·42 to 0·72) for at least 41 versus 1-10 procedures per year) and gastrectomy (odds ratio 0·64 (0·41 to 0·99) for at least 21 versus 1-10 procedures per year).

CONCLUSION

Hospitals performing larger numbers of oesophagogastric cancer resections had a lower 30-day mortality rate. Differences in outcomes between several European countries could not be explained by differences in hospital volumes. To understand these differences in outcomes and resection rates, with reliable case-mix adjustments, a uniform European upper gastrointestinal cancer audit with recording of standardized data is warranted.

Expression of cell adhesion molecules and prognosis in breast cancer

Background

Cell adhesion molecules (CAMs) play an important role in the process of metastasis. The prognostic value of tumour expression of N-cadherin, E-cadherin, carcinoembryonic antigen (CEA) and epithelial CAM (Ep-CAM) was evaluated in patients with breast cancer.

Methods

A tissue microarray of the patient cohort was stained immunohistochemically for all markers and analysed by microscopy. Expression was classified into two categories, with the median score as cut-off level. For CEA, the above-median category was further subdivided in two subgroups based on staining intensity (low or high intensity).

Results

The cohort consisted of 574 patients with breast cancer with a median follow-up of 19 years. Below-median expression of E-cadherin (P = 0·015), and above-median expression of N-cadherin (P = 0·004), Ep-CAM (P = 0·046) and CEA (P = 0·001) all resulted in a shorter relapse-free period. Multivariable analysis revealed E-cadherin and CEA to be independent prognostic variables. Combined analysis of CEA and E-cadherin expression showed a 3·6 times higher risk of relapse for patients with high-intensity expression of CEA, regardless of E-cadherin expression, compared with patients with below-median CEA and above-median E-cadherin tumour expression (hazard ratio 3·60, 95 per cent confidence interval 2·12 to 6·11; P &lt; 0·001). An interaction was found between expression of these two CAMs (P &lt; 0·001), suggesting a biological association.

Conclusion

Combining E-cadherin and CEA tumour expression provides a prognostic parameter with high discriminative power that is a candidate tool for prediction of prognosis in breast cancer.

The Eurotransplant donor risk index in liver transplantation: ET-DRI

Recently we validated the donor risk index (DRI) as conducted by Feng et al. for the Eurotransplant region. Although this scoring system is a valid tool for scoring donor liver quality, for allocation purposes a scoring system tailored for the Eurotransplant region may be more appropriate. Objective of our study was to investigate various donor and transplant risk factors and design a risk model for the Eurotransplant region. This study is a database analysis of all 5939 liver transplantations from deceased donors into adult recipients from the 1st of January 2003 until the 31st of December 2007 in Eurotransplant. Data were analyzed with Kaplan-Meier and Cox regression models. From 5723 patients follow-up data were available with a mean of 2.5 years. After multivariate analysis the DRI (p < 0.0001), latest lab GGT (p = 0.005) and rescue allocation (p = 0.007) remained significant. These factors were used to create the Eurotransplant Donor Risk Index (ET-DRI). Concordance-index calculation shows this ET-DRI to have high predictive value for outcome after liver transplantation. Therefore, we advise the use of this ET-DRI for risk indication and possibly for allocation purposes within the Eurotrans-plant region.

Influence of hospital type on outcomes after oesophageal and gastric cancer surgery

BACKGROUND

Outcomes after oesophagectomy and gastrectomy vary considerably between hospitals. Possible explanations include differences in case mix, hospital volume and hospital type. The present study examined the distribution of oesophagectomies and gastrectomies between hospital types in the Netherlands, and the relationship between hospital type and outcome.

METHODS

Data were obtained from the nationwide Netherlands Cancer Registry. Hospitals were categorized as university hospitals (UH), non-university teaching hospitals (NUTH) and non-university non-teaching hospitals (NUNTH). Hospital type-outcome relationships were analysed by Cox regression, adjusting for case mix, hospital volume, year of diagnosis and use of multimodal therapies.

RESULTS

Between 1989 and 2009, 10 025 oesophagectomies and 14 221 gastrectomies for cancer were performed in the Netherlands. The percentage of oesophagectomies and gastrectomies performed in UH increased from 17·6 and 6·4 per cent respectively in 1989 to 44·1 and 12·9 per cent in 2009. After oesophagectomy, the 3-month mortality rate was 2·5 per cent in UH, 4·4 per cent in NUTH and 4·1 per cent in NUNTH (P = 0·006 for UH versus NUTH). After gastrectomy, the 3-month mortality rate was 4·9 per cent in UH, 8·9 per cent in NUTH and 8·7 per cent in NUNTH (P < 0·001 for UH versus NUTH). Three-year survival was also higher in UH than in NUTH and NUNTH.

CONCLUSION

Oesophagogastric resections performed in UH were associated with better outcomes but, owing to variation in outcomes within hospital types, centres of excellence cannot be designated solely on hospital type. Detailed information on case mix and outcomes is needed to identify centres of excellence.

Long-term cosmetic changes after breast-conserving treatment of patients with stage I-II breast cancer and included in the EORTC 'boost versus no boost' trial

BACKGROUND

In breast cancer treated with breast-conserving radiotherapy, the influence of the boost dose on cosmetic outcome after long-term follow-up is unknown.

PATIENTS AND METHODS

We included 348 patients participating in the EORTC 'boost versus no boost' mega trial with a minimum follow-up of 6 years. Digitalised pictures were analysed using specific software, enabling quantification of seven relative asymmetry features associated with different aspects of fibrosis.

RESULTS

After 3 years, we noted a statistically significantly poorer outcome for the boost patients for six features compared with those of the no boost patients. Up to 9 years of follow-up, results continued to worsen in the same magnitude for the both patient groups. We noted the following determinants for poorer outcome: (i) boost treatment, (ii) larger excision volumes, (iii) younger age, (iv) tumours located in the central lower quadrants of the breast and (v) a boost dose administered with photons.

CONCLUSIONS

A boost dose worsens the change in breast appearance in the first 3 years. Moreover, the development of fibrosis associated with whole-breast irradiation, as estimated with the relative asymmetry features, is an ongoing process until (at least) 9 years after irradiation.

Quality of life in relation to tamoxifen or exemestane treatment in postmenopausal breast cancer patients: a Tamoxifen Exemestane Adjuvant Multinational (TEAM) Trial side study

Tamoxifen and aromatase inhibitors are associated with side effects which can significantly impact quality of life (QoL). We assessed QoL in the Tamoxifen Exemestane Adjuvant Multinational (TEAM) Trial and compared these data with reported adverse events in the main database. 2,754 Dutch postmenopausal early breast cancer patients were randomized between 5 years of exemestane, or tamoxifen (2.5–3 years) followed by exemestane (2.5–2 years). 742 patients were invited to participate in the QoL side study and complete questionnaires at 1 (T1) and 2 (T2) years after start of endocrine treatment. Questionnaires comprised the EORTC QLQ-C30 and BR23 questionnaires, supplemented with FACT-ES questions. 543 patients completed questionnaires at T1 and 454 patients (84 %) at T2. Overall QoL and most functioning scales improved over time. The only clinically relevant and statistically significant difference between treatment types concerned insomnia; exemestane-treated patients reported more insomnia than tamoxifen-treated patients. Discrepancy was observed between QoL issue scores reported by the patients and adverse events reported by physicians. Certain QoL issues are treatment- and/or time-specific and deserve attention by health care providers. There is a need for careful inquiry into QoL issues by those prescribing endocrine treatment to optimize QoL and treatment adherence.

Locoregional recurrence after breast-conserving therapy remains an independent prognostic factor even after an event free interval of 10 years in early stage breast cancer

INTRODUCTION

Locoregional recurrence (LRR) after breast-conserving therapy is a well-known independent risk factor associated with unfavourable long-term outcome. Controversy exists concerning the prognostic impact of a LRR after a very long event-free interval.

METHOD

Patients who underwent breast-conserving therapy for early stage breast cancer were pooled from four European Organisation for Research and Treatment of Cancer (EORTC) Breast Group trials. Only LRR as a first event was taken into account. Risk factors such as tumour size, nodal status, young age and chemotherapy were assessed in multivariate Cox regression analysis. LRR was used as a time-dependent variable in the landmark analysis for distant disease-free survival (DFS) and overall survival (OS). Patients were categorised as having at least 0, 5 or 10 years event-free survival.

RESULTS

In total, 7751 early stage breast cancer patients were included with a median follow-up of 10.9 years. Tumour size, nodal status, young age and chemotherapy are strong independent prognostic factors with a significant impact on long-term outcome, but lose their power and significance over time. Including all patients, LRR was the strongest prognostic factor for OS and distant DFS (resp. HR 5.01 and HR 5.31, p<0.001). In the subgroup of patients developing a LRR after at least 5 or 10 years, LRR remained the strongest independent prognostic factor for OS (resp. HR 3.98, HR 4.96, p ≤ 0.001) and distant DFS (HR 4.42, HR 7.57 p<0.001).

CONCLUSION

This is the first study which shows LRR after breast-conserving therapy is a very strong, time-independent prognostic factor for long term outcome in early stage breast cancer patients. These findings suggest that a LRR after a long event-free interval seems to be an indicator rather than an instigator of subsequent distant disease.

Vertical modelling: Analysis of competing risks data with missing causes of failure

We propose vertical modelling as a natural approach to the problem of analysis of competing risks data when failure types are missing for some individuals. Under a natural missing-at-random assumption for these missing failure types, we use the observed data likelihood to estimate its parameters and show that the all-cause hazard and the relative hazards appearing in vertical modelling are indeed key quantities of this likelihood. This fact has practical implications in that it suggests vertical modelling as a simple and attractive method of analysis in competing risks with missing causes of failure; all individuals are used in estimating the all-cause hazard and only those with non-missing cause of failure for relative hazards. The relative hazards also appear in a multiple imputation approach to the same problem proposed by Lu and Tsiatis and in the EM algorithm. We compare the vertical modelling approach with the method of Goetghebeur and Ryan for a breast cancer data set, highlighting the different aspects they contribute to the data analysis.

Abstract P4-07-02: Expression of Cell Adhesion Molecules Predicts Prognosis in Early Breast Cancer Patients

Purpose: New prognostic and predictive factors are sought for improvement of tailored treatment in early breast cancer. We examined the clinical impact of cell adhesion molecules (CAM): E-cadherin, N-cadherin, Ep-CAM and CEA.

Patients and Methods: Our study population (n=574) consisted of all early breast cancer patients primarily treated with surgery in our center between 1985 and 1994. A tissue micro array (TMA) of formalin-fixed paraffin-embedded tumor tissue was immunohistochemically stained for expression of mentioned CAM. The percentage of membranous stained cells was microscopically analyzed. Based on the median score, all CAM were classified in two groups: low expression versus high expression. For CEA, high expression was further subdivided based on the intensity of staining: high expression and highest expression. Results: High expression was seen for E-cadherin, N-cadherin and Ep-CAM in 49%, 46%, 27% of patients respectively. Low expression, high expression and highest expression were found in respectively 48%, 45% and 8% of cases for CEA. Low expression of E-cadherin (p=0.015) and higher expression levels of N-cadherin, Ep-CAM, CEA (p=0.004; 0.046; 0.001 respectively) all resulted in a worse relapse free period (RFP) of patients. Multivariate analysis revealed only E-cadherin and CEA to be independent prognostic variables. A combination variable was created with expression of both markers: (1) E-cadherin high expression, (2) E-cadherin low or CEA low or high expression (3) CEA highest expression. This variable revealed to be an independent prognostic parameter with high discriminative power for RFP (P&lt;0.001, E-cadherin low or CEA low or high expression versus E-cadherin high expression: Hazard Ratio (HR)= 1.9; CEA highest expression versus E-cadherin high expression: HR= 3.6). A statistically significant interaction was found between expression of both CAM (P&lt;0.001), suggesting a biological connection in their functioning.

Conclusion: We have demonstrated that E-cadherin, N-cadherin, Ep-CAM and CEA are of prognostic influence on outcome concerning RFP in breast cancer patients. A combined variable of E-cadherin and CEA expression revealed to have prognostic influence on RFP with high discriminative power and therefore is a candidate parameter for future outcome prediction of patients.

Abstract S2-3: The Impact of Body Mass Index (BMI) on the Efficacy of Adjuvant Endocrine Therapy in Postmenopausal Hormone Sensitive Breast Cancer (BC) Patients; Exploratory Analysis from the TEAM Study

Background: Obesity is associated with an increased risk of breast cancer (BC) recurrence and decreased survival, also in case of adjuvant endocrine therapy. It is still not clear whether the activity of aromatase inhibitors and tamoxifen (T) given as adjuvant therapy is affected by body mass index (BMI), although both drugs are widely prescribed. In this analysis, we explored the outcome of TEAM patients (pts) treated with exemestane (E) versus T (2.75 yrs), and with E versus T followed by E (T/E) (5 yrs) in relation to BMI.

Patients and Methods: The TEAM trial is a randomized, international phase III study in postmenopausal hormone sensitive early BC pts comparing the activity and safety of adjuvant E (25 mg daily) or the sequence of T (20 mg daily) followed by E (T/E), both regimens given for five years. WHO BMI definitions were used: normal 18.5-24.9 kg/m2, overweight 25-30 kg/m2, obese &gt;30 kg/m2. Disease-free survival (DFS) and overall survival (OS) were calculated by Kaplan-Meier method; results were compared by using the log-rank test and Cox proportional hazard modelling adjusted for country.

Results: Weight and height was known in 4741 pts. Mean BMI was 26.9 kg/m2 (SD 4.9); 39% had a normal BMI, 36.9% overweight, and 23.3% of pts was obese. Underweight pts (n=41, 0.9%) were excluded from further analysis. At 2.75 yrs (E vs T) disease relapse in normal weight, overweight and obese pts using E was observed in 8.1%, 6.8% and 7.5% respectively (p=0.57), and in 9.1%, 8.8%, and 12.5%, respectively (p=0.06) of pts using T. The hazard ratio (HR for risk of relapse on E vs T) in the three subgroups was 0.91 (95%CI 0.66-1.24), 0.78 (95%CI 0.55-1.089), and 0.57 (95%CI 0.39-0.84, p=0.004), respectively. At a median follow-up of 5.1 years, disease relapse in normal weight, overweight and obese pts using E occurred in 14.8%, 15.1% and 15.1%, respectively; and in pts using T in 17.0%, 16.9%, and 18.3%, respectively. Regarding DFS, the HR in normal weight, overweight, and obese pts was 0.87 (95%CI 0.69-1.10), 0.88 (95%CI 0.70-1.11), and 0.75 (95%CI 0.56-1.01, p=0.058), respectively, and with respect to OS 0.87 (95%CI 0.65-1.15, p= 0.32), 0.89 (95%CI 0.67-1.18, p= 0.43), and 0.71 (95% CI 0.51-1.01, p= 0.053), respectively.

Conclusions: After 2.75 years more disease events were observed in obese women using tamoxifen, which was not seen in obese exemestane users, whereas at 5 years these differences in disease recurrences disappeared in this group. In contrast to recent reports, there seems to be a difference regarding the influence of a high BMI on recurrence rate between tamoxifen and the aromatase inhibitor exemestane. Further research on this topic is warranted.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr S2-3.

Abstract P3-10-33: Mammostrat® as an Immunohistochemical Multigene Assay for Prediction of Early Relapse Risk in Postmenopausal Early Breast Cancer: Preliminary Data of the TEAM Pathology Study

Background: Postmenopausal early breast cancer patients, treated with endocrine therapy, have approximately 90% five year disease free survival (DFS). However, for patients at higher risk of relapse, additional adjuvant chemotherapy may be indicated. The challenge is to prospectively identify such patients. The Mammostrat test uses five immunohistochemical markers to stratify patients on tamoxifen (T) therapy into various risk groups potentially guiding treatment choices. We tested the efficacy of this panel in the TEAM trial (exemestane (E) versus T→E) to determine the relevance in patients treated with an AI.

Patients & Methods: Pathology blocks from 4598 TEAM patients were collected and tissue microarrays constructed. The cohort overall was 47% node positive, and 36% also received adjuvant chemotherapy. Samples were stained, using triplicate 0.6mm2 TMA cores, and positivity for p53, HTF9C, CEACAM5, NDRG1, SLC7A5 assessed. Each case was assigned a Mammostrat risk score and analysed for disease free survival (DFS) by marker positivity and risk score.

Results: Preliminary results on the UK TEAM cohort (1059 cases) showed 18.9% stained positive for p53 (184/972), 21.3% for NRDG1 (204/956), 26.4% for SLC7A (253/957), 21.9% for HTF9C (220/1004), 18.3% for CEACAM5 (185/1009). Complete data was available for 919 cases including patients treated with chemotherapy, with 447 (49%) designated low risk, 213 (23%) medium and 259 (28%) high risk. In univariate analysis, Mammostrat scores were prognostic (p=0.02), with 5 year DFS (see comment above) results being 86.9±1.7%, 80.1±3.0% and 80.8±2.6% for patients with low, medium and high Mammostrat scores respectively. Analyses on the entire TEAM pathology cohort are ongoing, and further data with sufficient power to evaluate the impact of Mammostrat in multivariate regression analyses will be presented. Conclusion: Preliminary analysis of the impact of the Mammostrat score in both tamoxifen and exemestane treated patients suggests it retains its prognostic value in this context. Further analysis with the power to evaluate the impact of Mammostrat in multivariate regression analyses will be presented.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-33.