Zhou et al. BMC Cancer 2010, 10:653 http://www.biomedcentral.com/1471-2407/10/653 Page 6 of 8 (a) (b) Figure 1 Kaplan-Meier analyses of local recurrence and invasive- and general recurrence by DCIS molecular subgroup by immunohistochemistry. (a) Local recurrence (in situ or invasive) in women with a primary DCIS, undergoing breast-conserving surgery (BCS), by molecular subtype. (b) Invasive- or general recurrence in all women with a primary DCIS by molecular subtype. National Guidelines from the Swedish Breast Cancer Group [35]. In this study, grade did not relate to prog- nosis (see Table 2) and molecular subtyping by IHC might indeed be more useful. We also investigated the prognosis of triple-negative DCIS. In invasive cancer, triple-negative tumors have been shown to have a worse prognosis [36-38]. We observed a slightly elevated risk for developing inva- sive disease, but this was not statistically significant. In some studies, triple-negative and basal-like DCIS cases have been considered to have a fairly similar prognosis. In our study, there was a considerable miss-match between these cases as already described in invasive breast cancer by others [21,39,40]. Conclusions In conclusion, basal-like DCIS showed about a doubled, however not statistically significant risk for local recur- rence and developing invasive cancer compared with the other molecular subtypes. In this study, molecular sub- typing was a better prognostic parameter than histo- pathological grade. (a) (b) Figure 2 Kaplan-Meier analysis of local recurrence and invasive- and general recurrence by triple-negative and non triple-negative DCIS. (a) Local recurrence (BCS), triple negative DCIS vs. non-triple negative DCIS. (b) Invasive- or general recurrence in all women, triple negative DCIS vs. non-triple negative DCIS.