Using the 21-gene assay to guide adjuvant chemotherapy decision-making in early-stage breast cancer: a cost-effectiveness evaluation in the German setting

OBJECTIVE

The 21-gene assay (Oncotype DX Breast Cancer Test (Genomic Health Inc., Redwood City, CA)) is a well validated test that predicts the likelihood of adjuvant chemotherapy benefit and the 10-year risk of distant recurrence in patients with ER+, HER2- early-stage breast cancer. The aim of this analysis was to evaluate the cost-effectiveness of using the assay to inform adjuvant chemotherapy decisions in Germany.

METHODS

A Markov model was developed to make long-term projections of distant recurrence, survival, quality-adjusted life expectancy, and direct costs for patients with ER+, HER2-, node-negative, or up to 3 node-positive early-stage breast cancer. Scenarios using conventional diagnostic procedures or the 21-gene assay to inform treatment recommendations for adjuvant chemotherapy were modeled based on a prospective, multi-center trial in 366 patients. Transition probabilities and risk adjustment were based on published landmark trials. Costs (2011 Euros (€)) were estimated from a sick fund perspective based on resource use in patients receiving chemotherapy. Future costs and clinical benefits were discounted at 3% annually.

RESULTS

The 21-gene assay was projected to increase mean life expectancy by 0.06 years and quality-adjusted life expectancy by 0.06 quality-adjusted life years (QALYs) compared with current clinical practice over a 30-year time horizon. Clinical benefits were driven by optimized allocation of adjuvant chemotherapy. Costs from a healthcare payer perspective were lower with the 21-gene assay by ∼€561 vs standard of care. Probabilistic sensitivity analysis indicated that there was an 87% probability that the 21-gene assay would be dominant (cost and life saving) to standard of care.

LIMITATIONS

Country-specific data on the risk of distant recurrence and quality-of-life were not available.

CONCLUSIONS

Guiding decision-making on adjuvant chemotherapy using the 21-gene assay was projected to improve survival, quality-adjusted life expectancy, and be cost saving vs the current standard of care women with ER+, HER2- early-stage breast cancer.

Abstract P2-10-25: Prognostic value of relative change in tumor marker CA 27.29 in early stage breast cancer – The SUCCESS trial

Background: MUC1 based tumor markers like CA27.29 (TM) in breast cancer are routinely used in metastatic disease as early marker for treatment efficacy. However, in early stage disease data is sparse. In this analysis, we looked at the impact of individual change in CA27.29 on prognosis instead of using a threshold.

Methods: The SUCCESS Trial compares FEC-docetaxel (Doc) vs. FEC-Doc-Gemcitabine (Doc-G) regime and two vs. five year treatment with Zoledronat in 3754 patients (pts) with primary breast cancer (N+ or high risk N0). We measured CA27.29 after surgery but before chemotherapy (CHT) as baseline and compared it to CA27.29 levels 2 years thereafter with the ST AIA-PACK Ca27.29 reagent using MUC-1 for AIA-600II (Tosoh Bioscience, Tessenderlo, Belgium).

Results: CA27.29 data is available of 2,015 pts. 119 pts (5.9%) had TM over the threshold of 32U/ml before CHT and 56 (2.8%) 2years thereafter. To examine the relative change of tumor marker, pts were divided into 3 groups:

increase: change >=5 U/ml; stable: change <±5U/ml; decrease: change > = −5 U/ml.

123 (6.1%) pts had increasing (>=5 U/ml), 1419 (70.4%) had stable, 473 (23.5%) had decreasing TM levels from before CHT to 2 years thereafter. The majority of pts with increasing TM (86 pts; 69.9%) had levels below the usual threshold of 32U/ml at all times. Patients with an increase >=5 U/ml had an 81% increased risk for recurrence (HR = 1.810 [CI: 1.111–2.948]) and reduced overall survival (HR = 1.020 [CI: 1.004–1.037]). In the multivariate analysis taking into account tumor size, nodal status, grading, age, hormonal and HER2/neu receptor status increasing CA27.29 levels were an independent prognostic marker.

Conclusions: An increase of the tumor marker CA27.29 2 years after CHT compared to pre-chemotherapy baseline was associated with a worse prognosis. By using this approach, more patients at risk for recurrence were detected than with the standard threshold approach. Therefore, the use of relative change could help to identify more patients at risk for relapse who might benefit from an intensified follow up.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-25.

Abstract P1-14-01: Adding capecitabine and trastuzumab to neoadjuvant breast cancer chemotherapy - first survival analysis of the GBG/AGO intergroup-study GeparQuattro

Background: Previous results of the GeparQuattro study demonstrated that adding capecitabine either simultaneously or sequentially to EC-Docetaxel (D) neoadjuvant chemotherapy could not increase pathological complete response rates (pCR) (von Minckwitz G, JCO 2010). However, patients with HER2-positive disease treated simultaneously with trastuzumab showed a significant higher pCR rate than patients with HER2-negative disease treated with chemotherapy alone (Untch M, JCO 2010). We here report survival after a median follow up of 58 months including 279 relapses and 191 deaths.

Patients and methods: Patients with either large operable (cT3) and locally advanced (cT4) tumors, or hormone-receptor (HR)-negative receptor status, or HR-positive tumors but clinically node-positive disease were recruited to receive 4 cycles of EC (90mg/m2/600mg/m2) and randomized to either 4 cycles of D (100mg/m2) or 4 cycles of DX (75mg/m2/1800mg/m2) or 4 cycles of D (75mg/m2) followed by 4 cycles of X (1800mg/m2) (D→X). Patients with HER-2 positive tumors received 1 year of trastuzumab, the first part concurrent to all chemotherapy cycles. All patients with HR+ tumors received endocrine therapy according to current standard. The intent-to-treat survival analysis included 1421 patients for the chemotherapy question and 1495 patients for the trastuzumab question. Analyses were adjusted by age, stage, size, nodal status, histologic type, grade, hormone-receptor (HR) and HER2-status at baseline (if applicable).

Results: No difference in DFS and OS was seen for patients receiving D, DX or D-X overall (hazard ratio 0.978, p = 0.984 and hazard ratio 0.986, p = 0.684, respectively) as well as by phenotype defined according to St. Gallen (all P>0.354).

Patients with HER2-positive disease treated additionally with trastuzumab showed significantly better OS (p = 0.015) compared to patients with HER2-negative disease treated with chemotherapy alone. DFS was significantly better for trastuzumab-treated patients with HR-negative tumors (p = 0.046), but not with HR-positive tumors (p = 0.790). OS after first relapse was significantly better in trastuzumab-retreated patients with HER2-positive tumors (p = 0.032) compared to relapsed patients with HER2-negative tumors.

Patients with an early response after 4 cycles, with a clinical response at surgery and with a pCR showed a significantly better DFS and OS compared to patients without pCR (p = 0.022, P < 0.0001, P < 0.0001). This benefit was most prominent in patients with triple-negative tumors.

Conclusions: Survival analysis of the GeparQuattro study confirmed the results of the primary endpoint analysis on pCR. Capecitabine could not improve outcome when added to anthracycline-taxane-based chemotherapy. As suggested by a recent integrated multi-level meta-analysis (von Minckwitz, BCRT 2011) effect of capecitabine could not be properly assessed in this study as planned docetaxel doses in arms DX and D®X were lower than in arm D. Survival of HER-2 positive patients surmounts that of HER2-negative patients if trastuzumab is used in the neoadjuvant as well as in the metastatic setting.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-14-01.

The 21-gene recurrence score assay impacts adjuvant therapy recommendations for ER-positive, node-negative and node-positive early breast cancer resulting in a risk-adapted change in chemotherapy use

Background

We carried out a prospective clinical study to evaluate the impact of the Recurrence Score (RS) on treatment decisions in early breast cancer (EBC).

Patients and methods

A total of 379 eligible women with estrogen receptor positive (ER+), HER2-negative EBC and 0–3 positive lymph nodes were enrolled. Treatment recommendations, patients' decisional conflict, physicians' confidence before and after knowledge of the RS and actual treatment data were recorded.

Results

Of the 366 assessable patients 244 were node negative (N0) and 122 node positive (N+). Treatment recommendations changed in 33% of all patients (N0 30%, N+ 39%). In 38% of all patients (N0 39%, N+ 37%) with an initial recommendation for chemoendocrine therapy, the post-RS recommendation changed to endocrine therapy, in 25% (N0 22%, N+ 39%) with an initial recommendation for endocrine therapy only to combined chemoendocrine therapy, respectively. A patients' decisional conflict score improved by 6% (P = 0.028) and physicians' confidence increased in 45% (P < 0.001) of all cases. Overall, 33% (N0 29%, N+ 38%) of fewer patients actually received chemotherapy as compared with patients recommended chemotherapy pre-test. Using the test was cost-saving versus current clinical practice.

Conclusion

RS-guided chemotherapy decision-making resulted in a substantial modification of adjuvant chemotherapy usage in node-negative and node-positive ER+ EBC.

Preventing Unnecessary Invasive Cancer-Diagnostic Tests: Changing the Cut-off Points

BACKGROUND

To determine a cut-off point of tPSA and PSAD to prevent unnecessary invasive cancer-diagnosing tests in the community.

METHODS

This study was performed on 688 consecutive patients referred to our center due to prostatism, suspicious lesions on digital rectal examination and/or elevated serum PSA levels. All patients underwent transrectal ultrasound guided biopsies and obtained PSAD. Serum levels of tPSA and fPSA were measured by chemiluminescence. Comparisons were done using tests of accuracy (AUC-ROC).

RESULTS

Prostate cancer was detected in 334 patients, whereas the other 354 patients were suffering from benign prostate diseases. The mean tPSA in case and control groups were 28.32±63.62 ng/ml and 7.14±10.04 ng/ml; the mean f/tPSA ratios were 0.13± 0.21 and 0.26±0.24 in PCa and benign prostate disease groups; the mean PSAD rates were 0.69±2.24, 0.12±0.11, respectively. Statistically significant differences were found (P <0.05). Using ROC curve analysis, it was revealed that AUC was 0.78 for tPSA and 0.80 for f/tPSA. Sensitivity was 71% for the cut-off value of 7.85ng/ml. For f/tPSA ratio, the optimal cut-off value was 0.13 which produced the sensitivity of 81.4% and for PSAD, it was15%.

CONCLUSIONS

As this trial is different from the European and American values, we should be more cautious in dealing with the prostate cancer upon the obtained sensitivity and specificity for PCa diagnosis (7.85ng/mL for tPSA, 15% for PSAD and 0.13 for f/tPSA ratio).

S3-6: Neoadjuvant Chemotherapy of Paclitaxel with or without Rad001: Results of the Non-Responder Part of the GEPARQUINTO Study (GBG 44)

Background:

The oral signal transduction inhibitor everolimus (RAD001 = R), binds selectively to mTOR (mammalian target of rapamycin), an intracellular protein kinase implicated in the control of cellular proliferation of activated T-lymphocytes and neoplastic cells. Phase II data suggested that R can enhance the clinical efficacy of endocrine treatment in the metastatic and neoadjuvant setting.

The GeparQuinto phase III study had 3 settings (HER2−positive: trastuzumab vs lapatinib; HER2−negative: +/− bevacizumab (Bev); HER2−negative non-responder: +/− R). Primary aim of the last setting was to improve pathological complete response (pCR) for patients with HER2−negative breast cancer not responding to 4x epirubicin/cyclophosphamide (EC) +/− Bev by adding R to weekly paclitaxel as neoadjuvant chemotherapy.

Patients and Methods:

Patients with untreated HER2−negative breast cancer were eligible if their tumors were stage cT3/4a-d; or estrogen (ER) and progesterone (PgR) receptor-negative; or ER/PgR-positive tumors with clinically N+ (for cT2) or pNSLN+ (for cT1). Only patients without response (&lt;50% tumor reduction) to 4x EC+/−Bev were eligible and were randomized to receive further paclitaxel (Pac: 80 mg/m2 q1w x12) chemotherapy with or without R. Treatment with R started 21 to 35 days after the last application of EC with a dose escalation from 2.5 mg every 2nd day to 5 mg every day over 14 days and maintained at 5 mg/day for additional 10 weeks. Dose of R could be decreased to 2.5 mg/day in case of toxicity. Treatment with Pac started within 7–14 days after the start of R. pCR was defined as no invasive and no non-invasive tumor residuals in breast and nodes. We assumed a pCR rate of 5% for Pac based on the GeparDuo study and expected a pCR of 12.1% for Pac+R (odds ratio 2.62). A two-sided Pearson's C2 with a=0.05 and β=0.20 calculated a sample size of 566 P. One interim futility analysis after 1/3 of patients completed therapy was planned. Randomisation was stratified by participating center, ER/PgR status, extend of disease (T4 or N3 vs. T1-3 and N0-2) and pre-treatment with Bev or not.

Results:

Between 11/07 and 15/06/11 402 P were randomized to Pac (N=201) and Pac+R (N=201). Median age was 51.0 and 50.0 [-R/+R] years. Median clinical tumor size was 40/40 mm; 62%/55% had cT2, 18% / 20% cT3, and 16.7% / 16.7% cT4a-d tumors; 88% / 89% had non-lobular; 35% / 33% grade 3; 55% / 57% node-positive; and 29% / 27% ER and PgR-negative (triple-negative) disease.

The futility interim analysis was performed in 02/10, futility boundary was not reached and the trial was continued. After the other 2 settings completed accrual in 06/10, recruitment to the 3rd setting dropped such that it appeared not possible to recruit the full number of patients.. The trial will therefore close recruitment on June, 30th 2011 with an estimated statistical power of 65%. Results on histological response and surgical outcome will be reported.

Conclusion:

This will be the first report on efficacy data of neoadjuvant R + Pac for patients with early breast cancer. The results of the GeparQuinto study will have to be set into context with the results from the Bolero studies in metastatic disease.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr S3-6.

P4-07-06: Correlation of Two Analytical Methods for Circulating Tumor Cells in Peripheral Blood of Patients with Primary Breast Cancer

Background

While the evidence for circulating tumor cells (CTCs) as a prognostic marker in metastatic breast cancer has been well established, there is still a lack of data in primary disease. In the SUCCESS A trial two different techniques for the detection of CTCs in early breast cancer were prospectively evaluated.

Material and Methods: SUCCESS A compared FEC-Docetaxel vs. FEC-Docetaxel-Gemcitabine and 5 vs. 2 years of treatment with zoledronic acid in primary breast cancer patients and node positive or high-risk node negative disease. Two different techniques to detect CTCs were prospectively evaluated in two consecutive, but comparable subgroups of the whole study population.

In 3515 samples the CellSearch® System (Veridex, Warren, USA) was used for CTC detection. Immunomagnetic enrichment with an EPCAM-antibody was followed by labeling with monoclonal antibodies specific for cytokeratin (8, 18, 19) and leukocytes (CD45). 2165 samples were evaluated with a manual immunocytochemistry (MICC) protocol. Cytospins were prepared after mononuclear cell enrichment based on Oncoquick® centrifugation (greiner bio-one, Frickenhausen, Germany). Staining was performed with the monoclonal pancytokeratin antibody A45-B/B3 (Micromet, Munich, Germany) and the APAAP technique. Conventional light field microscopy (Axiophot; Zeiss, Oberkochen, Germany) was used for the detection of stained cells.

For both methods, the cut-off value for positivity was ≥ 1 CTC. All events were evaluated by two independent observers.

Results: CTCs were examined in a total number of 3243 patients before and after chemotherapy (CHT). The two subgroups evaluated with one or the other method were well-balanced regarding clinical parameters as tumor size, grading, lymph node-status, hormone receptors and Her2. Furthermore there was no significant correlation between the CTC positivity and one of these clinical parameters using CellSearch or the MICC, respectively (p &gt; 0,05 using the chi square test each time).

Before adjuvant CHT 21. 3% (424 out of 1994) and 21.1 % (264 out of 1249) of the patients were found positive for CTCs using CellSearch® or the MICC respectively, with a mean CTC level of 5.9 (range: 1 to 827) and 3.1 (range: 1 to 256).

Immediately after CHT 21.9% (333 out of 1521) and 16.5% (151 out of 916) of the patients were positive for CTCs using CellSearch® or the MICC. The mean CTC level decreased to 3.0 (range: 1 to 124) and 2.1 (range: 1 to 23) in both analytical methods.

Using CellSearch® there was a significant correlation between the presence of CTCs before CHT and disease progression (p = 0.0044), as well as survival (p = 0.0001), whereas the MICC did not predict any of these (p = 0.3143 and p = 0.0801 respectively; the chi-square test was used each time).

Conclusion: We found comparable prevalence of CTCs before and after adjuvant chemotherapy both with the CellSearch® System or the MICC. However, prognostic relevance could only be shown for CTCs detected with the CellSearch® System. This may be attributed to the high standardization and reproducibility of the automated system, as well as the additional CD45 counterstaining. According to our findings, the FDA approved CellSearch® System should be used as gold standard for CTC detection in future clinical trials.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-07-06.

P5-14-05: Anti-Müllerian Hormone (AMH) Levels in Premenopausal Breast Cancer Patients Treated with Adjuvant Chemotherapy – A Translational Research Project of the SUCCESS Study

Background: Premenopausal women undergoing chemotherapy are at risk of premature ovarian failure and long term side-effects caused by premature menopause. However, knowledge about the rate of ovarian failure and potential markers to evaluate the ovarian reserve is limited, especially in the context of modern chemotherapy concepts. Therefore, Anti-Müllerian hormone (AMH) was measured at before, immediately after and 2 years after chemotherapy in premenopausal patients of the SUCCESS study.

Materials and Methods: The German SUCCESS trial is a multicenter phase III study comparing FEC-Docetaxel vs. FEC-Docetaxel+Gemcitabine as adjuvant treatment in patients with node positive or high risk node negative primary breast cancer. Blood samples were taken prior to and 4 weeks after last cycle of adjuvant chemotherapy, as well as after 2 years of follow up. We retrospecitvely identified 170 patients stratified premenopausal and aged 40 years or younger at trial entry, who received 3cycles of FEC (500/100/500mg/m2) q3w followed by 3 cycles of docetaxel (100mg/m2) q3w as one of the most commonly used chemotherapy regimens in Europe. Serum AMH levels were evaluated in a central laboratory by a manual immunoassay AMH DSL ELISA (Diagnostic Systems Laboratories, Webster, USA).

Results: Median age within this subgroup was 36 years (21-40 years). 48% of the patients had a tumor stage pT1 and 54% were node positive. 69% were hormone receptor positive and 29% Her2 positive. Median serum AMH level before adjuvant chemotherapy was 1.32 ng/ml (range &lt;0.1−11.32). Immediately after chemotherapy AMH levels dropped in 96% of the patients below the threshold of detection (&lt;0.1 ng/ml, range &lt;0.1−3.9ng/ml). No association to classical prognostic markers, such as tumor stage, lymph node involvement, etc. was observed. After a follow up period of 2 years, serum was available from 95 patients. 76% of those patients showed no evidence of ovarian function indicated by AMH (&lt;0.1 ng/ml, range &lt;0.1−1.43ng/ml). AMH levels prior to and 2 years after chemotherapy were significantly correlated with older age, with a reduction of 0.14 ng/ml per life year (p=0.0025) and 0.01 ng/ml (p=0.017) respectively. 12 patients (7%) received optional gonadotropin-releasing hormone (GnRH) agonists during chemotherapy. These patients presented significantly higher AMH levels (+ 0.18 ng/ml; p=0.01) 2 years after cytotoxic treatment. Conclusion: In this retrospective analysis premenopausal patients showed a high rate of ***f ovarian insufficiency reflected by low serum AMH levels immediately after cytotoxic treatment and after 2 years of follow up. GnRH agonists given as ovarian protectants during chemotherapy may have an influence on serum AMH 2 years after chemotherapy. Further data from prospective trials with longer follow up are needed to evaluate the role of serum AMH as a predictor of ovarian failure in breast cancer patients exposed to chemotherapy.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-05.

Microarray-based gene expression profiles to predict ELISA-derived uPA and PAI-1 levels in breast cancer biopsies: A comparison between fresh frozen (FF) and formalin-fixed, paraffin-embedded (FFPE) samples

194

Background: The urokinase plasminogen-activator (uPA) and its inhibitor (PAI-1) predict the benefit of node-negative breast cancer patients from chemotherapy. The determination of uPA and PAI-1 need(s) large amounts of tumor tissue. In contrast, microarray-based gene expression profiling (MGEP) requires only small quantities of FF tissue and is applicable to FFPE archival tissue. Identification of MPEG-derived surrogate markers for ELISA-based uPA/PAI-1 may facilitate their analysis together with MPEG-based predictive genes and metagenes.

Methods: Three groups of breast cancer biopsies were analysed. Group A: 136 FF tissues from 2008-2009, group B: 85 FF tissues from 2010, group C: 20 independent FFPE tissues. Gene expression was assessed by Agilent 4x44K microarrays.

Results: For group A a significant correlation between protein expression of uPA and uPA gene (PLAU) expression (r = 0.627 p < 0.001) and PAI-1 and PAI-1 genes (SERPINE1)(r = 0.281 p = 0.001) was found. Top sets of genes correlated with uPA/PAI-1 protein expression were extracted. For group B additional sets of top correlated genes were identified. The correlation of individual genes with uPA/PAI-1 protein expression was highest for their genes themselves (PLAU: r = 0.694 p < 0.001; SERPINE1 (r = 0.469 p < 0.001). Subsequently consensus gene sets were identified with a good performance for both biopsy sets. Only genes which were significantly correlated with their counterparts in group C were selected, resulting in a final 11-gene model (uPA metagene) and a 6-gene model (PAI-1 metagene). They significantly correlated with uPA/PAI-1 protein expression in all groups of biopsies (uPA: group A: r = 0.621, p < 0.001; group B: r = 0.771, p < 0.001; group C: r = 0.665, p = 0.005; for PAI-1: group A: r = 0.569, p < 0.001; group B: r = 0.687, p < 0.001; group C: r = 0.683, p = 0.008).

Conclusions: Reliable MPEG-derived metagenes as surrogate markers for ELISA-based uPA/PAI-1 expression were identified.

Changes in arterial stiffness but not carotid intimal thickness in acromegaly

CONTEXT

Acromegaly increases cardiovascular morbidity. We tested the hypothesis that increased arterial stiffness together with left ventricular hypertrophy may be a contributory factor.

PATIENTS AND DESIGN

Fifty-six patients (40 males, 54 ± 13 yr; 25 active disease, 31 in remission) and 46 healthy controls (30 males, 52 ± 13 yr) underwent measurements of aortic pulse wave velocity (PWV), carotid Doppler (IMT), echocardiography, and cardiovascular risk factors.

RESULTS

Mean serum IGF-I was 323 ± 286 ng/ml (sd score 1.8 ± 1.9) in all patients. Age, body mass index, diastolic blood pressure (BP), and lipid levels were similar comparing patients and controls. Systolic BP (130.8 ± 19.9 vs. 122 ± 14 mm Hg controls, P < 0.01) and PWV (11.7 ± 3.8 vs. 9.7 ± 2.8 m/sec, 95% confidence interval -3.4 to -0.7, P <0.01) were higher in patients than controls. Regression analysis revealed age, presence of acromegaly, systolic BP, and body mass index, inversely, as significantly and independently associated with PWV. No difference in carotid IMT was seen (0.8 ± 0.2 patients vs. 0.7 ± 0.2 mm controls, P = 0.5) or between active/controlled disease. In the subset of participants with echocardiography (n = 32), left ventricular mass was higher by a mean of 38.2 g (95% confidence interval -80.9 to +4.6, P = 0.08).

CONCLUSION

In summary, patients with acromegaly had independently and significantly increased aortic PWV as evidence of arterial stiffening but unaltered carotid IMT compared with controls, also influenced by age and systolic BP. Premature cardiovascular disease in patients with acromegaly is likely related to pressure-related arterial and left ventricular stiffening rather than atherosclerotic disease.