This study suggests that the amount of prognostic information contained in four widely performed IHC assays is similar to that in the GHI-RS. Additional studies are needed to determine the general applicability of the IHC4 score.

Purpose To evaluate the relative effectiveness of letrozole compared with tamoxifen for patients with invasive ductal or lobular carcinoma. Patients and Methods Patients diagnosed with early-stage invasive ductal carcinoma (IDC) or classic invasive lobular carcinoma (ILC) who were randomly assigned onto the Breast International Group (BIG) 1-98 trial and who had centrally reviewed pathology data were included (N = 2,923). HER2-negative IDC and ILC were additionally classified as hormone receptor–positive with high (luminal B [LB] –like) or low (luminal A [LA] –like) proliferative activity by Ki-67 labeling index. Survival analyses were performed with weighted Cox models that used inverse probability of censoring weighted modeling. Results The median follow-up time was 8.1 years. In multivariable models for disease-free survival (DFS), significant interactions between treatment and histology (ILC or IDC; P = .006) and treatment and subgroup (LB like or LA like; P = .01) were observed. In the ILC subset, there was a 66% reduction in the hazard of a DFS event with letrozole for LB (hazard ratio [HR], 0.34; 95% CI, 0.21 to 0.55) and a 50% reduction for LA subtypes (HR, 0.50; 95% CI, 0.32 to 0.78). In the IDC subset, there was a significant 35% reduction in the hazard of a DFS event with letrozole for the LB subtype (HR, 0.65; 95% CI, 0.53 to 0.79), but no difference between treatments was noted for IDC and the LA subtype (HR, 0.95; 95% CI, 0.76 to 1.20). Conclusion The magnitude of benefit of adjuvant letrozole is greater for patients diagnosed with lobular carcinoma versus ductal carcinoma.

Background:Immunohistochemistry of Ki-67 protein is widely used to assess tumour proliferation, and is an established prognostic factor in breast cancer. There is interest in automating the assessment of Ki-67 labelling index (LI) with possible benefits in handling increased workload, with improved accuracy and precision.Patients and methods:Visual and automated assessment of Ki-67 LI and survival were examined in patients with primary operable invasive ductal breast cancer. Tissue microarrays (n=379 patients) immunostained for Ki-67 were scored visually and automatically with the Slidepath Tissue IA system.Results:Visual and automated Ki-67 LI were in excellent agreement (ICCC=0.96, P<0.001). On univariate analysis, visual (P<0.001) and automated Ki67 LI (P<0.05) were associated with cancer-specific survival in patients with invasive ductal breast cancer overall and in patients who received endocrine therapy (Tamoxifen) (P<0.01 for visual and P<0.05 for automated scoring).Conclusion:Automated assessment of Ki-67 LI would appear to be comparable to visual Ki-67 LI. However, automated Ki-67 LI assessment was inferior in predicting cancer survival in patients with breast cancer, including patients who received Tamoxifen.

BackgroundSeveral well-established tumour prognostic factors are used to guide the clinical management of patients with breast cancer. Lymphovascular invasion and angiogenesis have also been reported to have some promise as prognostic factors. The aim of the present study was to examine the prognostic value of tumour lymphovascular invasion and microvessel density compared with that of established prognostic factors in invasive ductal breast cancer.MethodsIn addition to hormone receptor status and Ki-67 proliferative activity, lymphovascular invasion and microvessel density and their relationship with survival were examined in patients with invasive ductal breast cancer. Full sections and tissue microarrays (n = 384 patients) were utilised to assess these factors and were scored by appropriate methods.ResultsOn univariate analysis tumour size (P < 0.05), lymph node involvement (P < 0.01), lymphovascular invasion (P < 0.05), microvessel density (P < 0.05) and local- regional treatment (P < 0.01) were associated with poorer survival in ER negative tumours. On multivariate analysis in ER negative tumours lymph node involvement (P < 0.01) and local- regional treatment (P < 0.05) were independently associated with poorer cancer-specific survival. On univariate analysis tumour grade (P < 0.05), lymph node involvement (P < 0.001), HER-2 (P < 0.05), Ki-67 (P < 0.01) and lymphovascular invasion (P < 0.001) were associated with poorer survival in ER positive tumours. On multivariate analysis lymph node involvement (P < 0.001), Ki-67 (P < 0.001) and lymphovascular invasion (P < 0.05) were independently associated with poorer cancer-specific survival in ER positive tumours.ConclusionLymphovascular invasion but not microvessel density was independently associated with poorer survival in patients with ER positive but not ER negative invasive ductal breast cancer.

AUS is inferior in detecting axillary node metastasis in ILC compared with IDC. Women with cT3-4 lobular carcinoma may benefit from ultrasound-guided axillary biopsy regardless of the ultrasonographic appearance of the nodes.