An Epidermal Growth Factor Receptor Intron 1 Polymorphism in Healthy Women in Poland

The frequency of CA allele combinations was assessed in healthy women from Poland and compared to previously published polymorphism data of individuals from Germany and a Caucasian reference group. There were close similarities between these three geographically and ethnically similar populations. By contrast, the distribution of these alleles in European and Asian (Japan) populations proved to be different. There might therefore be major ethnic differences in allelic frequencies of EGFR intron 1 polymorphism. Our results provide new data on EGFR microsatellite instability and may contribute to the understanding of EGFR gene expression regulation. The clinical relevance of these findings warrants further evaluation.

Cardiac safety, efficacy, and correlation of serial serum HER2-extracellular domain shed antigen measurement with the outcome of the combined trastuzumab plus CMF in women with HER2-positive metastatic breast cancer: results from the EORTC 10995 phase II study

PURPOSE

Cardiotoxicity is a side effect of trastuzumab. We assessed efficacy and cardiac safety of CMF with trastuzumab (CMF+T) in HER2-positive metastatic breast cancer patients (MBC).

METHODS

In this phase II study, centrally confirmed, previously treated HER2-positive MBC patients with measurable disease (per RECIST v 1.0) were enrolled. Initially, patients were randomized between 8 CMF cycles alone or combined with trastuzumab during chemotherapy, followed by 3-weekly trastuzumab maintenance till progression. A protocol amendment dropped the CMF arm and thereafter all patients received CMF+T. Translational research for prediction of treatment benefit was performed through serial serum HER2-shed antigen assessments.

RESULTS

Ninety patients (CMF: 19; CMF+T: 71) were enrolled between 2002 and 2006. Median age was 54 years. 42 patients had prior chemotherapy (33 with anthracyclines) and 41/71 patients who received CMF+T continued trastuzumab monotherapy for a median duration of 40 weeks. Overall response rate was 50% for CMF+T (35/70) and 32% for CMF (6/19). Median duration of response was 10.3 months and 5.4 months, respectively. Median progression-free survival was 9.4 months (95% CI 8.1-11.6) and 4.8 months (95% CI 2.8-7.9), respectively. In the CMF+T arm, 13(18%) patients had an absolute LVEF decline, including 3 patients developing any grade of New York Heart Association cardiac dysfunction. Patients with an increase of 30% over baseline shed antigen had a higher progression risk (95% CI 7.6, 3.9-14.8).

CONCLUSIONS

CMF+T is effective, with an acceptable cardiotoxicity profile. LVEF declines were mostly asymptomatic and occurred irrespective of previous anthracycline exposure. CMF+T can be considered for these patients, if other cytotoxics are contraindicated.

Abstract P5-04-01: Expression of epithelial-mesenchymal transition (EMT)-related markers in primary tumors and matched lymph node metastases in breast cancer patients

Background. Malignant tumors may include multiple cancer cell populations with various metastatic potential. More aggressive subpopulations might easier be captured in lymph nodes metastases (LNM) than in primary tumors (PT). We evaluated mRNA and protein levels of master EMT regulators: TWIST1, SNAIL and SLUG, protein levels of EMT-related markers: E-cadherin, vimentin, and expression of classical breast cancer receptors: HER2, ER and PR in PT and corresponding LNM. The results were correlated with clinicopathological data and patient outcomes.

Methods. Formalin-fixed paraffin-embedded (FFPE) samples from PT and matched LNM from 42 stage II-III breast cancer patients were examined. Expression of TWIST1, SNAIL and SLUG was measured by RT-qPCR, with median as cut off for positive result. Protein expression was examined by immunohistochemistry on tissue microarrays. For TWIST1, SNAIL, SLUG, E-cadherin and vimentin >10% of positively stained cells defined positive result. ER and PR were scored according to Allred system, and HER2 - according to HercepTest criteria. Results were considered concordant if PT and LNM were both positive or both negative. Concordance was measured by estimating Cohen's kappa coefficient (κ), with κ value equal 1 indicating perfect agreement. Disease-free survival (DFS) and overall survival (OS) were compared using F-Cox test. Hazard ratios (HRs) with 95% confidence intervals (95% CI) were computed using Cox regression analysis.

Results. On average, expression of TWIST1, SNAIL and SLUG was significantly higher in LNM compared to PT (P < 0.00001 for all). Gene and protein levels of TWIST1, SNAIL and SLUG were highly discordant between PT and matched LNM (Tab 1). Receptor conversion, particularly loss of ER and PgR, occurred in 18% and 29% of cases, respectively. Increased expression of TWIST1 and SNAIL in LNM was associated with shorter OS (p = 0.045 and p = 0.022, respectively) and DFS (p = 0.02 and p = 0.01, respectively), whereas their expression in PT had no prognostic impact. Negative-to-positive switch of TWIST, SNAIL and vimentin correlated with shorter OS and DFS. Conversion of ER and PR had no significant impact on survival.

Conclusions. LNM are enriched in cells with more aggressive phenotype, marked by elevated levels of EMT regulators. High expression of TWIST1 and SNAIL in LNM, as well as negative-to-positive conversion of both TWIST1 and SNAIL confer worse prognosis, confirming the correlation of EMT with aggressive disease behavior.

P53 functional assay in yeast: evaluation in 1856 patients in a large prospective clinical trial (EORTC 10994/BIG 00-01)

Abstract #1067

Background:Although mutations in the p53 gene can occur in 20-30% of sporadic breast cancer, and are associated with other poor prognostic factors, there is no clear evidence as to whether p53 status should influence therapy. Immunohistochemistry has been demonstrated to be an inferior method compared with sequencing, but the optimal technique to assess the functional p53 status is not known. The yeast test is a functional assay which tests the transcriptional competence of p53, and detects biologically important mutations. Here we present the results of p53 evaluation using this method in a prospective study.
 Material and methods: EORTC 10994/BIG 00-01 trial is a randomized trial comparing the neoadjuvant use of an anthracycline-based regimen with a taxane-containing regimen in patients with large operable or locally advanced breast cancers. Fresh frozen tumour biopsies were mandatory before starting chemotherapy. Frozen sections were examined centrally and the p53 test was done if the invasive tumour cell content was above 20%. RNA extract was used to assess p53 status: p53 wild type tumours were defined as tumours whose cDNA transfected in yeast gave less than 20% red colonies (background); p53 mutated tumours gave 20% or more red colonies.
 Results: The trial accrual was completed in November 2006 after inclusion of 1856 patients. There was no frozen sample available in 70 patients. In 276 patients the % of tumour cells was <20. The p53 test failed in 62 patients, generally because the quality or quantity of RNA was too low for RT-PCR. P53 was successfully assessed in 1458 patients: 661 (45%) tumours are p53 mutated and 797 (55%) are p53 wt. p53 mutated and wild type tumours were grade III in 40% (265/661) and 19% (153/797), respectively, and estrogen receptor negative in 41% (270/661) and 14.5% (116/797), respectively. We did not see any correlation between p53 status and tumour size or nodal status at diagnosis. HER2 status data are being collected.
 Conclusion: P53 status has been successfully evaluated using a yeast assay in 78.5% (1458/1856) of cases in the context of a multicenter trial. In indirect comparisons the frequency of patients with functionally altered p53 status is higher than with sequenced based methods. Our results confirm an association between p53 mutation and high grade or estrogen receptor negative status, but not with age, tumour size or clinical nodal status. More data regarding the quality and quantity of RNA collected will be presented at the meeting.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1067.

Safety and efficacy of combined trastuzumab and CMF therapy in women with metastatic breast cancer: EORTC protocol 10995

1040

Background: Safety and efficacy of classical CMF combined with 3-weekly Trastuzumab (T), followed by T alone in metastatic breast cancer (MBC). Methods: Patients (pts) with previously treated MBC were enrolled into a Phase II study of T (4 mg/kg then by 2 mg/kg) IV weekly plus CMF, Bonadonna regimen, for a maximum of 8 cycles (cy), followed by T alone (6 mg/kg) IV 3 weekly. Entry criteria included HER2 overexpression, limited anthracycline (A) exposure, normal baseline LVEF and measurable disease (RECIST). Cardiac endpoints were defined as: symptomatic CHF or LVEF drop by ≥ 15% from baseline or to ≥ 5% below lower limit. Results: The trial was closed to recruitment in January 2006, 12 pts are still on treatment. Seventy one pts were entered with a median age of 54 (range 31–75). Forty-one pts had prior CT (32 A), of which 26 adjuvant, 6 MBC, and 9 both adjuvant and MBC. Median PS was 0, 52 pts had visceral disease with a median interval from diagnosis to first relapse of 33.4 months (mo). Out of 70 pts receiving T+CMF (33 pts with 8 cy), 42 continued with T alone for a median duration of 7 cy. Eleven pts discontinued treatment for toxicity (9 on T+CMF, 2 on T alone). To date, the overall response rate is 55% (31/56 pts): 55% (23/42) 1st line; 57% (8/14) 2nd line. An independent review of responses is on-going. Median time to response was 2 mo, median duration of response was 8.3 mo and the median progression free survival was 9.2 mo. The most common grade 3–4 toxicity was neutropenia (53 %). Fourteen pts had cardiac toxicities, one NYHA grade 2 CHF, 6 pts with a drop in LVEF of 15% from baseline after a median of 3 mo of treatment, 9 pts with a drop in LVEF of 5% below LLN, after a median of 8 mo of treatment. The other toxicities included one grade 3 arrhythmia, two grade 3 hypertension, one grade 2 SVT, one grade 3 thrombosis, and one grade 2 dyspnea. One pt previously exposed to A had NYHA grade 4 CHF one year after treatment discontinuation. Conclusions: Combination of T+CMF regimen is feasible treatment for HER2+ MBC patients. The safety profile was acceptable, with cardiac toxicity and neutropenia within previously reported range. Drops in LVEF were mostly asymptomatic irrespective of previous exposure to A. Preliminary response data confirm good efficacy of CMF+T in MBC patients.

[Table: see text]

Locoregional control significantly reduces the risk of subsequent distant metastases in patients with locally advanced breast cancer managed with radiotherapy as the primary locoregional treatment

11076

Background: The treatment results of patients with locally advanced breast cancer still remain far from satisfactory. Both lack of locoregional control and distant metastases remain the most common pattern of failuire. The aim of this study was to evaluate whether achieving locoregional control decreases the subsequent risk of distant metastases a large series of consecutive locally advanced breast cancer patients managed with radiotherapy as the primary locoregional treatment. Methods: The records of 261 primarily inoperable locally advanced breast cancer patients treated between 1991 and 1997 at two institutions: Medical University of Gdansk, Poland and Velindre NHS Trust, Cardiff, UK were analysed. All patients received megavoltage radiotherapy to the breast with two tangential fields, and the adjacent lymph node areas were irradiated using customised fields. In 241 patients radiotherapy constituted the only local treatment and the remaining 20 patients were subsequently subjected to mastectomy. Most patients received chemotherapy and/or endocrine therapy prior or after radiation therapy. Results: Follow-up ranged from 6 to 133 months (median 37 months). Five- year overall survival was 36% (95%CI: 28–43%) and 5-year loco-regional relapse-free survival was 48% (95%CI: 40–57%). Recurrence occurred in 167 patients (67%), including local recurence in 30 patients (12%), distant metastases - in 72 patients (27%) and both distant and local recurrence - in 65 patients (26%). Median time to distant metastases was significantly shorter among a subgroup of patients who presented locoregional failuire - 33 months as compared to patients who were free of locoregional recurrence or progression before presenting distant metastases-43 months (p<0.05) Conclusions: This study demonstrated that treatment results in patients with locally advanced breast cancer are still far from satisfactory. However it confirmed the importance of putting much effort in achieving locoregional control in that group of patients as it significantly reduces the risk of subsequent distant metastases.

No significant financial relationships to disclose.

An epidermal growth factor receptor intron 1 polymorphism in healthy women in Poland

The frequency of CA allele combinations was assessed in healthy women from Poland and compared to previously published polymorphism data of individuals from Germany and a Caucasian reference group. There were close similarities between these three geographically and ethnically similar populations. By contrast, the distribution of these alleles in European and Asian (Japan) populations proved to be different. There might therefore be major ethnic differences in allelic frequencies of EGFR intron 1 polymorphism. Our results provide new data on EGFR microsatellite instability and may contribute to the understanding of EGFR gene expression regulation. The clinical relevance of these findings warrants further evaluation.

An epidermal growth factor receptor intron 1 polymorphism in healthy women in Poland

The frequency of CA allele combinations was assessed in healthy women from Poland and compared to previously published polymorphism data of individuals from Germany and a Caucasian reference group. There were close similarities between these three geographically and ethnically similar populations. By contrast, the distribution of these alleles in European and Asian (Japan) populations proved to be different. There might therefore be major ethnic differences in allelic frequencies of EGFR intron 1 polymorphism. Our results provide new data on EGFR microsatellite instability and may contribute to the understanding of EGFR gene expression regulation. The clinical relevance of these findings warrants further evaluation. (Int J Biol Markers 2005; 20: 184-8).

Final results of a randomized phase III trial comparing cyclophosphamide, epirubicin, and fluorouracil with a dose-intensified epirubicin and cyclophosphamide + filgrastim as neoadjuvant treatment in locally advanced breast cancer: an EORTC-NCIC-SAKK multicenter study

PURPOSE

To compare the efficacy of a standard anthracycline-based regimen to a dose-intensified anthracycline regimen in locally advanced breast cancer.

PATIENTS AND METHODS

Locally advanced breast cancer patients were randomly assigned onto a study comparing cyclophosphamide (C; 75 mg/m(2) orally days 1 to 14), epirubicin (E; 60 mg/m(2) intravenously [IV] days 1, 8), and fluorouracil (F; 500 mg/m(2) IV days 1, 8) six cycles every 28 days versus E (120 mg/m(2) IV day 1), C (830 mg/m(2) IV day 1), and granulocyte colony-stimulating factor (filgrastim; 5 micro g/kg/d subcutaneously days 2 to 13) six cycles every 14 days. The study was designed to detect a 15% improvement; that is, from 50% to 65% in median progression-free survival (PFS) in favor of the dose-intensified regimen.

RESULTS

A total of 448 patients were enrolled over a period of 3 years. The median dose intensity delivered for C and E reached, respectively, 85% and 87% of that planned in the CEF arm and 96% and 95% of that planned in the EC arm. The dose-intensified arm was slightly more emetogenic and generated more grade 3 to 4 anemia but less febrile neutropenia episodes. After a median follow-up of 5.5 years, 277 events have been reported. The median PFS was 34 and 33.7 months for CEF and EC, respectively (P =.68), and the 5-year survival rate was 53% and 51% for CEF and EC, respectively (P =.94).

CONCLUSION

Dose-intensified EC does not provide a measurable therapeutic benefit over CEF as neoadjuvant chemotherapy for unselected locally advanced breast cancer patients.