Participation in the SUCCESS-A Trial Improves Intensity and Quality of Care for Patients with Primary Breast Cancer

The SUCCESS-A trial is a prospective, multicenter, phase III clinical trial for high-risk primary breast cancer. It compares disease-free survival after randomization in patients treated with fluorouracil, epirubicin and cyclophosphamide followed by 3 cycles of docetaxel (FEC-D) with that of patients treated with 3 cycles of FEC followed by 3 cycles of gemcitabine and docetaxel (FEC-DG). After a second randomization patients were treated with zoledronate for 2 or 5 years. A total of 251 centers took part in the trial and 3754 patients were recruited over a period of 18 months which ended in March 2007. In a questionnaire-based survey we investigated the impact of enrollment in the trial on patient care, the choice of chemotherapy protocol and access to current oncologic information as well as overall satisfaction in the respective centers. Analysis of the 78 questionnaires returned showed that 40 % of the centers had never previously enrolled patients with these indications in clinical studies. Prior to participating in the study, 4 % of the centers prescribed CMF or other protocols in patients with high-primary breast cancer risk, 46 % administered anthracycline-based chemotherapy and 50 % gave taxane-based chemotherapy. Around half of the participating centers noted that intensity of care and overall quality of care became even better and that access to breast cancer-specific information improved through participation in the trial. After their experience with the SUCCESS-A trial, all of the centers stated that they were prepared to enroll patients in clinical phase III trials again in the future. These data indicate that both patients and physicians benefit from clinical trials, as enrollment improves treatment strategies and individual patient care, irrespective of study endpoints.

Abstract P2-01-02: Circulating Tumor Cells (CTC) may Express HER2/neu in Patients With Early HER2/neu Negative Breast Cancer – Results of the German SUCCESS C Trial

Background: There is growing evidence that the HER2/neu-status of distant metastases or minimal residual disease in blood and bone marrow may differ from the primary tumor in patients with breast cancer. The HER2/neu-status of CTCs was prospectively evaluated in patients with HER2/neu negative primary breast cancer randomized into the German multicenter SUCCESS C study.

Methods: The SUCCESS C trial is a randomized Phase III study comparing FEC-Docetaxel (FEC-Doc) vs. Docetaxel-Cyclophosphamid (DC) as well as 2 years of a lifestyle-intervention in patients with early, HER2/neu negative, node positive or high-risk node negative primary breast cancer.

As part of the translational research program, 23ml peripheral blood were drawn after adjuvant chemotherapy. In 505 samples, the prevalence of CTCs and their HER2/neu-status were assessed using the CellSearch System (Veridex, USA). After immunomagnetic enrichment with an anti-Epcam-antibody, cells were labelled with anti-CK8/18/19 and anti-CD45 antibodies. A fluorescein conjugate antibody with anti-CK-Fluorescein Isothiocyanate (FITC) was used for HER2/neu phenotyping. The cut-off for CTC-positivity was ≥ 1 CTC and for HER2/neu ≥ 1 CTC with strong HER2/neu-staining (+++).

Results: 26,9% of pts (n = 136) were positive for CTCs (mean 1.78; range 1–7; median = 1). The number of detected CTC was distributed as follows: 1 CTC (n = 76; 55.9%), 2 CTCs (n = 35; 25.7%), 3 CTCs (n = 13; 9.6%), 4 CTCs (n = 7; 5.2%) and ≥ 5 CTCs (n = 5; 3.7%). HER2/neu staning of CTCs was not detectable or weak in 26.5% (n = 36) and 4.4% (n = 6) of CTC positive patients respectively and therefore categorized as HER2/neu negative. In 32.4% of the CTC-positive patients (n = 44), we detected moderate and in 36.8% (n = 50) strong HER2/neu-staining of ≥ 1 CTC per sample. No association was found between CTCs or the HER2/neu-status of CTCs with tumor size, histopathological grading, hormone receptor status or axillary lymph node involvement.

Conclusions: The data of this trial confirm previous findings that patients with HER2/neu negative primary breast cancer can show HER2/neu positive minimal residual disease. These results underline the importance of frequent HER2/neu determination during follow up and disease progression. Survival data within the Success C trial will give further insight into the tumor biology of HER2/neu negative disease.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-01-02.

Abstract P4-13-11: Prognostic factors in young breast cancer patients over time – a 40 year longitudinal analysis

Background: In younger patients (pts) breast cancer (BC) is associated with a worse prognosis compared to older pts. Only few data are available presenting the development of prognostic factors regarding a period of several decades. This 40 year (y) longitudinal comparison of the main prognostic factors was performed to investigate differences in younger women with primary BC in contrast to older women over time.

Patients and Methods: In this retrospective analysis a consecutive pts cohort of 4010 pts was analyzed. Pts were documented and treated for primary invasive breast cancer between 1963 and 2003 at two University Hospitals in Germany. To be eligible, pts were required to have identified tumor characteristics, including TNM-status. Pts with carcinoma in situ or distant metastases were excluded. The cohort was divided in two age groups, ≤40y and >40y. Furthermore to reveal trends and changes over the duration of 41 years the period of analysis was split into 3 time frames: 1963–1976, 1977–1989 and 1990–2003. We analyzed the main prognostic factors for BC including tumor size, grading, nodal status and HR-status in longitudinal comparison regarding the three time frames, respectively. During 1963–77 HR-status was determined in just 12.6% of pts. Thus, this time frame was excluded in the analysis of HR-status.

Results: In 41 yrs, 747 (18.6%) pts were treated between 1963–76, 1722 pts (42.9%) in 1977–89 and 1541 pts (38.4%) in 1990–2003. Overall 358 pts were ≤40y and 3652 pts were over the age of 40.

A significant reduction of tumor size (metric assessment) at primary diagnosis was observed for both age groups (pts≤40y: p = 0.012; pts>40y: p < 0.0001) with no difference between the time frames, respectively (1963–76: p = 0.289; 1977–89: p = 0.647; 1990–2003: p = 0.937).

The number of node-positive pts significantly decreased in pts >40 y (p = 0.001) whereas no difference could be seen in pts aged ≤40 y (p = 0.991).

In both age groups the number of G2/3 tumors increased over the yrs (pts≤40y: p = 0.001; pts>40y: p < 0.0001). Between 1963–76 more G1-tumors were diagnosed in younger pts (p = 0.041) whereas in the two following periods significantly more G2/3 tumors (p = 0.001; p = 0.002) were observed in this group.

In young pts, 54.2% were HR-negative in 1977–89 and 47.6% in 1990–2003 (p = 0.323). In pts >40y 38.4% and 21.7% were HR-negative, respectively (p < 0.0001). Comparing the age groups, significantly more pts were HR-negative in the young patient group (p = 0.001 (1977–89) and p < 0.0001 (1990–2003)).

Conclusions: Concerning the large period of 40yrs, technical improvement and increasing awareness for BC are reasons for decreasing tumor size at the time of primary diagnosis. However, the rate of node-positive pts in the young patient group remained stable. Furthermore, the high percentage of HR-negative pts and the increasing number of pts with unfavorable tumor grade demonstrate more aggressive tumor types in younger pts. These data confirm the need to improve screening tools to early identify young women with the risk to develop breast cancer, and for personalized treatment approaches in these patients.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-13-11.

Abstract P2-01-11: Detection and characterization of circulating and disseminated tumour cells in blood and bone marrow of breast cancer patients by two different biochemical methods

Background: The main reason for breast cancer associated death are remote metastases, that are due to cells, that dissolve from the primary tumour, and are found in blood (circulating tumour cells, CTCs) and bone marrow (disseminated tumour cells, DTCs). The detection of these cells in breast cancer patients is mostly linked to a worse prognosis.

We present an immunohistochemical staining method for the detection of DTCs from bone marrow by using the cancer-associated Thomsen-Friedenreich antigen (TF) in combination with Her-2, and stem cell markers (Muc-1, ALDH1A1), and a highly sensitive RT-PCR based approach for CTC-detection from peripheral blood of adjuvant breast cancer patients using the established cytokeratin markers CK8, 18 and 19.

Materials and Methods: 20ml blood and 2–3ml of bone marrow were withdrawn from 20 respectively 40 primary breast cancer patients during surgery. For this investigation we used only samples of patients with at least one CTC already detected with the FDA approved VERIDEX CellSearch System.

RT PCR investigations blood samples from healthy donors were taken and used as control group.

For both methods an enrichment of mononuclear cell fraction, containing DTCs and CTCs, was carried out by density gradient centrifugation.

For immunohistochemical staining cells were spun down on coverslips fixed and stained with antibodies against Thomsen-Friedenreich-Antigen and Her-2, MUC1 or ALDH1A1.

For Real-Time PCR RNA was isolated from the cell pellet obtained by density gradient centrifugation, reversely transcribed to cDNA and RT-PCR was run with Taq-Man Primers against Cytokeratin (CK) 8, 18 and 19. The housekeeping gene 18S was used as internal reference.

Results: For the staining of Her-2 and TF, 78,01% of all samples showed at least one stained cell. The biggest subgroup within these samples was the double stained one with 46,14%.

In the other two experimental settings respectively the biggest cohorts were only single stained with TF (47,4% for TF-MUC1) or ALDH1A1 (59,65% for TF-ALDH1A1).

Within the PCR trials, the investigation between the negative control group and adjuvant breast cancer blood samples showed significant correlations for the expressions of CK8 (p < 0,047) and CK18 (p < 0,041). CK19 showed borderline significance (P < 0,057) of correlation.

Conclusion: The immunostaining-combination of diverse cell surface antigens for detection and characterization of DTCs, especially the TF antigen, in combination with Her-2, Muc-1 and ALDH1A1 is an excellent way to detect DTC's in bone marrow due to its significant correlations (p < 0.001).

The verification of CTC's by using RT-PCR is possible by using epithelial marker genes like the cytokeratins, especially CK8 and 18.

Both methods can be a step towards modern personalized medicine and lead to new ways of early tumour detection. Additionally an improved tumour characterization might ease the decision on specific medical treatment (eg against Her-2).

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-01-11.

P1-07-24: Quantitative and Immunohistochemical Detection of Breast Cancer Cells in Blood Samples

Background Disseminated tumor cells (DTCs) in bone marrow and circulating tumor cells (CTCs) in blood are found in patients with epithelial carcinomas (breast cancer) and are often correlated with poor prognosis of the disease. In current models circulating tumor cells (CTCs) dissolved from the primary tumor are thought to be responsible for the occurrence of metastases. However, the detection of CTCs is still a technical challenge. In this study, two methods for tumor cell detection of patients’ samples are presented (Real-Time-PCR and immunohisto-chemical staining). Both are simple and known methods with a high sensitivity and a spread marker panel.

Materials and Methods For the implementation of both methods, different breast cancer cell lines have been used (Cama-1, MCF-7; ZR-75-1). For Real-Time-PCR, blood samples of a healthy donors were spiked with different cell counts (0, 10, 100, 1000, 10.000 and 100.000) per ml blood sample. Total RNA was isolated from the samples, reversely transcribed into cDNA and used for TaqMan Real-Time-PCR reaction with probes against CK8, 18 and 19, while 18S was used as reference. Relative Quantification Curves were drawn by Microsoft™ Excel®. For immunohistochemical staining, cytospins were prepared from spiked blood samples, fixed with acetone, air dried and stained with antibodies against Her2- and Thomsen-Friedenreich-Antigen (CD176). In a second staining step fluorescently labelled secondary antibodies were applied. Nuclei were counterstained with DAPI, TF-Antigen was stained by Cy2 and Her2-Antigen by Cy3. The staining was controlled and documented by an epifluorescence microscope.

Results The curve of Relative Quantification for MCF-7 and ZR-75-1 cells shows an increasing slope starting from 1000 cells. For the Cama-1 cell line this trend is already seen from 10–100 cells. In ZR-75-1 all three genes analysed reveal this trend, whereas in Cama-1 and MCF-7 cells a strong increase in Relative Quantification is especially seen for CK8 and 18. In the immunohistochemical staining, the cells were considered as tumour cells if they showed staining with the antibody-combinations used. Stained cells were counted and recovery rates were determined. For ZR-75-1, 17 of 30 cells which were spiked in the blood samples were recovered. For MCF-7, 18 cells were found in average, and for Cama-1 23 cells were located per slide. The recovery rates calculated from these numbers are 56,6% and 60,0% for ZR-75-1 and MCF-7, for Cama-1 the recovery rate reaches 76,6%.

Conclusion It seems that Cama-1 cells are a better model than MCF-7 and ZR-75-1 for Real-Time PCR quantification of mamma carcinoma tumor cells in blood samples. MCF-7 and ZR-75-1 cells tend to react more likely immunologically with blood cells of the donor (agglutination between blood cells and cancer cells). The Cama-1 cell line shows also advantages in the detection of tumor cells using immunohistochemical staining. Therefore it will be necessary to test both methods on patient samples to proof their benefit.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-07-24.

Prognostic relevance of disseminated tumor cells in the bone marrow of patients with primary breast cancer--results of a standardized follow-up

BACKGROUND

The prognostic significance of disseminated tumor cells from bone marrow (BM-DTCs) of breast cancer patients has been demonstrated previously. In this study, data of a standardized long term follow-up of 829 patients with examination of BM-DTCs at primary diagnosis are presented.

PATIENTS AND METHODS

BM aspiration and immunocytochemical examination of DTCs was performed according to a standardized protocol. Follow-up data of all patients were adjusted with the cancer registries of southern Bavaria.

RESULTS

A total of 268 patients (32%) had BM-DTCs with a median of 2 (1-1223)/2 x 10⁶ cells. Positive BM findings correlated with tumor size (p=0.032), but not with other histopathological parameters. After a median follow-up of 73 months, BM-DTCs were highly relevant for the development of distant metastases (p=0.006) and, beneath standard histological parameters, reduced overall survival (p=0.038).

CONCLUSION

These results confirm the prognostic relevance of the detection of BM-DTCs. Newer methods, such as detection of circulating tumor cells in blood, will have to demonstrate comparable prognostic information in the future.

Abstract PD04-08: Circulating tumor cells (CTC) in peripheral blood of breast cancer patients two years after adjuvant chemotherapy depending on endocrine treatment — The German SUCCESS-Trial

Background: The prognostic significance of CTC in metastatic, as well as in primary breast cancer has been demonstrated (Rack et al., ASCO 2010). The optimal endocrine treatment strategy for postmenopausal patients (pts) with hormone sensitive breast cancer remains unclear.We analyzed the prevalence of CTC two years after primary diagnosis in patients with tamoxifen or anastrozole treatment.

Methods: As part of the translational research project of the German SUCCESS-trial, we analyzed 23ml of peripheral blood from 307 N+ and high risk N-postmenopausal pts with hormone sensitive breast cancer two years after adjuvant taxane based chemotherapy and with tamoxifen or anastrozole treatment. The presence of CTCs was assessed with the CellSearchSystem (Veridex, USA). After immunomagnetic enrichment with an anti-Epcam-antibody, cells were labelled with anti-cytokeratin (8,18,19) and anti-CD45 antibodies to distinguish between epithelial cells and leukocytes. Standard within the study was early switch treatment (tamoxifen for 2 years, followed by anastrozle), while pts with contraindications against tamoxifen were allowed to receive anastrozole up-front.

Results: In 10.1% of pts (n=31) >1 CTC was detected after the completion of chemotherapy (range 2-33), while 7.8% (n=24) presented with >1 CTC (range 2-99) two years after completion of chemotherapy. The median age in the tamoxifen group was 59.9 years and 59.8 in the anastrozole group. In the tamoxifen group, 33.0% of the pts had a pT1 tumor, 5.3% G1 grading and 21.6% of the pts were node negative. In the anastrozole group, 30.0% of the pts had a pT1 tumor, 7.5% G1 grading and 22.5% of the pts were node negative, respectively. None of these differences were statistically significant. After the completion of chemotherapy, 9.7% of the pts were CTC positive in the tamoxifen group (range number of cells: 2-33) and 11.3% in the anastrozole group (range of cells: 2-24), p=0.69. Two years after primary diagnosis, 7.9% of the pts were CTC positive in the tamoxifen group (range number of cells:2-99) and 7.5% in the anastrozole group (range cells: 2-5), p=0.90. Actuarial disease free and overall survival will be presented at the meeting.

Conclusions: The prognostic relevance of CTC in peripheral blood of early breast cancer patients both before and after chemotherapy has been demonstrated. The presented data will add information on the monitoring potential of CTC during adjuvant endocrine treatment.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD04-08.