Comparison of clinical, radiological and pathological assessment of response to neoadjuvant chemotherapy for primary breast cancer

Imaging breast cancer response during neoadjuvant systemic therapy

Neoadjuvant systemic therapy is used to enable breast-conserving surgery in patients with large primary operable breast cancers. It is important to be able to accurately assess response to systemic therapy, both to assist the surgeon and for prognostic purposes. Moreover, a proportion of women will fail to respond to treatment and would potentially benefit from either a change in therapy or earlier surgery rather than continuing completion of the planned course of treatment. Conventional techniques of assessing response (clinical examination, x-ray mammography and breast ultrasound) rely on changes in tumor size, which are often delayed and do not always correlate with pathologic response. This review examines the evidence for functional imaging techniques including scintimammography, functional computed tomography, dynamic magnetic resonance imaging, spectroscopy and positron emission tomography. These techniques measure changes in tumor vasculature, metabolism or proliferation and may prove to be earlier and more sensitive measures of response to systemic therapy, thus enabling tailoring of an individual's treatment.

Assessment of clinical response after two cycles of primary chemotherapy in breast cancer

BACKGROUND

Complete clinical (cCR) and pathological (pCR) response to neoadjuvant chemotherapy in breast cancer is associated with improved survival. Various imaging and immunological techniques have been tested as predictors of response early in the course of chemotherapy, but their predictive value has not been compared with that of a simple early clinical assessment.

PATIENTS AND METHODS

Two hundred breast cancer patients (T2-4, N0-1) were treated with neoadjuvant chemotherapy. Clinical response after two cycles of treatment was compared with final clinical and pathological response. The likelihood of achieving cCR or pCR was compared by response after two cycles.

RESULTS

Overall final clinical response rate was 79% (30.5% cCR and 11.9% pCR). After two cycles of chemotherapy, clinical response rate was 54.5%. For responders after two cycles, final cCR = 51.3% and pCR = 21.5%. For non-responders after two cycles, cCR = 5.5% and pCR = 1.2%. Response after two cycles predicts for pCR (P = 0.003; sensitivity 95.2%, specificity 52.9%).

CONCLUSIONS

Clinical response after two cycles of chemotherapy predicts for pCR and is a valid early endpoint that could be incorporated into the design of future neoadjuvant trials.

Changes of Topoisomerase IIα Expression in Breast Tumors after Neoadjuvant Chemotherapy Predicts Relapse-Free Survival

PURPOSE

To assess the value of changes in the expression of topoisomerase IIalpha (TopoII) and the proto-oncogene erbB-2 (HER-2) as predictors of relapse-free survival in women with operable breast cancer treated with anthracycline-based neoadjuvant chemotherapy.

PATIENTS AND METHODS

Seventy-seven patients with primary breast cancer who had undergone neoadjuvant anthracycline-based chemotherapy were included in the present study. TopoII and HER-2 were measured by immunohistochemistry in prechemotherapy and postchemotherapy (at the time of surgery) tumor specimens, and the value of their changes as predictors of relapse-free survival were evaluated by Kaplan-Meier and Cox proportional hazard regression analyses.

RESULTS

Neoadjuvant chemotherapy resulted in a significant reduction in the percentage of cells expressing TopoII (P < 0.0001). No significant change was observed for HER-2. TopoII and HER-2 expression before chemotherapy predicted tumor response to treatment. Changes in TopoII expression after chemotherapy were strongly associated with a poor relapse-free survival (P < 0.0001) in a Cox multivariate analysis adjusted for other clinicopathologic prognostic factors.

CONCLUSION

Changes in TopoII expression after anthracycline-based neoadjuvant chemotherapy is an independent predictor of a poor relapse-free survival in patients with breast cancer. Tumor cells displaying an increased TopoII expression after treatment may be responsible for relapses, and may, therefore, define a group of patients with anthracycline-resistant breast cancer.