Yi et al. BMC Cancer 2010, 10:527 http://www.biomedcentral.com/1471-2407/10/527 Table 2 Treatment Response According to Subtypes (n = 105 patients with measurable diseases) Median cycles Response CR PR SD PD Not evaluable Overall response rate Total (n = 105) 6.0 (1-12) 2 55 25 20 2 57 (54.3%) HR (n = 68) 5.9 (1-12) 2 36 19 11 0 38 (55.9%) HER2 (n = 14) 4.8 (1-9) 0 6 3 4 1 6 (42.9%) TN (n = 23) 5.6 (1-9) 0 13 4 5 1 13 (56.5%) Page 4 of 7 p 0.454 0.542 CR; complete response, PR; partial response, SD; stable disease, PD; progressive disease. phenotype was 8.1 months for TN (95% CI, 7.2-9.1 months), 9.1 months for HER2+ (95% CI, 1.3-16.8 months), and 11.5 months for HR+ (95% CI, 7.2-15.9 months; p = 0.0002 by log-rank test; Figure 1A). Overall survival With a median 55.8 months of follow-up (range, 29.2- 101.5 months), the median OS of all 110 patients was 32.4 months (95% CI, 28.5-36.3 months). The median OS was 25.4 months (95% CI, 17.9-32.9 months) in the TN subgroup and 27.3 months (95% CI, 9.3-45.3 months) in the HER2+ subgroup. The median OS for these two groups was significantly shorter than OS for HR+ patients (median, 38.5 months; 95% CI, 30.3-46.7 months; p < 0.0001). Most of the HER2+ patients did not receive trastuzumab as first-line treatment with che- motherapy (Figure 1B). Time-to-Death (TTD) from the end of AC chemotherapy There is a significant difference between patients with TN and non-TN phenotypes in terms of TTD after AC chemotherapy (median TTD 15.9 months, 95% CI, 7.8- 23.9 months for TN; median TTD 13.2 months, 95% CI, 9.7-16.7 months for HER2+; median TTD 24.8 months; 95% CI, 21.7-36.70 months for HR+; p < 0.0001). After AC chemotherapy, most of the patients were treated with additional 2nd or more lines of chemotherapies with various regimens including platinum and taxane agents. A median of three additional lines of palliative chemotherapies were undertaken for HR+ patients, whereas a median of two lines and one line of che- motherapies were performed for HER2+ and TNBC patients, respectively (p = 0.006). 17 of 71 (24%) of HR+ patients were treated with palliative endocrine treat- ment. 9 of 14 HER2+ patients received palliative trastu- zumab treatment with or without other cytotoxic agents. Multivariate analysis for survival The TN phenotype and HER2 positivity were identified as independent prognostic factors for survival in Cox- regression multivariate analysis (hazard ratio [HR] 2.03, p = 0.011 for TN; HR 1.86, p = 0.027 for HER2 positiv- ity) (Table 3). Discussion The present study demonstrates that TNBC has a simi- lar response rate to AC combination chemotherapy compared to other subtypes (Table 2). This encouraging result is in agreement with published data regarding Figure 1 Kaplan-Meier survival curves according to subtypes. A Progression-Free Survival (PFS) to AC chemotherapy. B Overall Survival (OS) to AC chemotherapy according to subgroups. C Overall Survival (OS) to AC chemotherapy in patients with TNBCs and non-TNBCs.