Breast cancer response to neoadjuvant chemotherapy: predictive markers and relation with outcome

Comparative value of tumour grade, hormonal receptors, Ki-67, HER-2 and topoisomerase II alpha status as predictive markers in breast cancer patients treated with neoadjuvant anthracycline-based chemotherapy

The aim of this study was to evaluate the predictive value of five different biological factors in breast cancer patients treated with neoadjuvant anthracycline-based chemotherapy: (1) tumour grade scored according to the Elston-Ellis classification, (2) hormonal receptor (HR) status; (3) tumour cell proliferation evaluated by Ki-67 staining, (4) HER-2 and topoisomerase II alpha (TopoIIalpha) expression evaluated by immunohistochemistry (IHC), (5) HER-2 and TopoIIalpha amplification evaluated by real-time polymerase chain reaction (PCR). 119 patients with operable breast cancer were treated with six cycles of FEC (100 5-fluorouracil (5-FU) 500 mg/m2, Epirubicin 100 mg/m2, Cyclophosphamide 500 mg/m2). Tumour response was assessed clinically and by computed tomography (CT) scan, then by pathological assessment. The clinical overall response (OR) was 80%, with 19% of complete responders (CR). The radiological OR was 71%, with 16% of CR. A pathological CR was demonstrated in 13% of the patients according to the Sataloff classification. In the multivariate analysis, the absence of HR expression and Ki-67 > or = 20% were predictive for a clinical CR. A high tumour grade was predictive for a pathological CR. Overexpression or amplification of HER2 or Topollcalpha were not predictive of response.

The prognostic relevance of estimates of proliferative activity in early breast cancer

AIMS

Immunohistochemical estimates of cell proliferation evaluated with MIB-1 antibody have been suggested as prognostic indicators in different types of carcinoma. This study investigates whether MIB-1 scores add additional prognostic impact when evaluated together with classical clinicopathological parameters at diagnosis in early breast cancer patients.

MATERIALS AND METHODS

Tumour specimens from 365 consecutively treated breast cancer patients were immunostained for MIB-1 and evaluated under the microscope using systematic random sampling accomplished by the CAST-grid system.

RESULTS

The systematic random sampling technique resulted in MIB-1 estimates with very high interobserver and intraobserver reproducibilities (P < 0.0001). Median MIB-1 was 16% (range 0-83%). Patients were stratified by MIB-1 in tertiles, and increasing MIB-1 was significantly associated with poor overall and disease-specific survival in node-positive patients, but not in node-negative patients. High MIB-1 was significantly related to large tumour size, and strongly associated with high grade, high mitotic score, negative oestrogen receptor status and young age. In multivariate analysis, both with and without malignancy grade and number of mitoses included in the analysis, MIB-1 estimates showed no independent prognostic impact.

CONCLUSIONS

High MIB-1 estimates did not add independent prognostic information at diagnosis when evaluated together with classical prognostic markers of early breast cancer.