Differential prognostic relevance of patho-anatomical factors among different tumor-biological subsets of breast cancer: Results from the adjuvant SUCCESS A study.

OBJECTIVES: In breast cancer, large tumor size, positive nodal stage and a triple-negative tumor subtype are associated with reduced survival, but the interactions between these prognostic factors are not well understood. MATERIAL AND METHODS: Here we re-evaluated the impact of tumor size, nodal stage and tumor subtype on disease-free survival (DFS), overall survival (OS), distant disease-free survival (DDFS) and breast cancer specific survival (BCSS) in a retrospective analysis using data from the adjuvant SUCCESS A trial. Subgroup analyses were conducted to assess whether the effect of tumor size and nodal stage on survival depended on tumor subtype. RESULTS: Increasing tumor size, higher nodal stage and triple negative breast cancer (TNBC) were associated with unfavorable prognosis (all p < 0.001). There was no significant interaction between tumor subtype and tumor size (p > 0.5 for all four survival endpoints), but we found significant interactions between tumor subtype and nodal stage (p < 0.05 for all four survival endpoints), with no differences in survival among tumor subtypes for patients with pN0 tumors (all p > 0.05) and pronounced differences in survival among tumor subtypes for patients with positive nodal stage (all p < 0.001). CONCLUSIONS: This analysis confirms tumor size, nodal stage and tumor subtype as independent prognostic factors in high-risk early breast cancer. Nodal-positive patients with TNBC had a considerably worse outcome compared to nodal-positive patients with another tumor subtype. This underlines the importance for early detection particularly for patients with TNBC. TRIAL REGISTRATION: EudraCT 2005-000490-21; ClinicalTrials.gov Identifier: NCT02181101.

Detection of circulating tumor cells using manually performed immunocytochemistry (MICC) does not correlate with outcome in patients with early breast cancer - Results of the German SUCCESS-A- trial.

BACKGROUND: Recently, the prognostic significance of circulating tumor cells (CTCs) in primary breast cancer as assessed using the Food-and-Drug-Administration-approved CellSearch® system has been demonstrated. Here, we evaluated the prognostic relevance of CTCs, as determined using manually performed immunocytochemistry (MICC) in peripheral blood at primary diagnosis, in patients from the prospectively randomized multicenter SUCCESS-A trial (EudraCT2005000490-21). METHODS: We analyzed 23 ml of blood from 1221 patients with node-positive or high risk node-negative breast cancer before adjuvant taxane-based chemotherapy. Cells were separated using a density gradient followed by epithelial cell labeling with the anti-cytokeratin-antibody A45-B/B3, immunohistochemical staining with new fuchsin, and cytospin preparation. All cytospins were screened for CTCs, and the cutoff for positivity was at least one CTC. The prognostic value of CTCs with regard to disease-free survival (DFS), distant disease-free survival (DDFS), breast-cancer-specific survival (BCSS), and overall survival (OS) was assessed using both univariate analyses applying the Kaplan-Meier method and log-rank tests, and using multivariate Cox regressions adjusted for other predictive factors. RESULTS: In 20.6 % of all patients (n = 251) a median of 1 (range, 1-256) CTC was detected, while 79.4 % of the patients (n = 970) were negative for CTCs before adjuvant chemotherapy. A pT1 tumor was present in 40.0 % of patients, 4.8 % had G1 grading and 34.6 % were node-negative. There was no association between CTC positivity and tumor stage, nodal status, grading, histological type, hormone receptor status, Her2 status, menopausal status or treatment. Univariate survival analyses based on a median follow-up of 64 months revealed no significant differences between CTC-positive and CTC-negative patients with regard to DFS, DDFS, BCSS, or OS. This was confirmed by fully adjusted multivariate Cox regressions, showing that the presence of CTCs (yes/no) as assessed by MICC did not predict DFS, DDFS, BCSS or OS. CONCLUSIONS: We could not demonstrate prognostic relevance regarding CTCs that were quantified using the MICC method at the time of primary diagnosis in our cohort of early breast cancer patients. Further studies are necessary to evaluate if the presence of CTCs assessed using MICC has prognostic relevance, or can be used for risk stratification and treatment monitoring in adjuvant breast cancer. TRIAL REGISTRATION: The ClinicalTrial.gov registration ID of this prospectively randomized trial is NCT02181101 ; the (retrospective) registration date was June 2014 (study start date September 2005).