Do breast cancer tumours downsize as well as downgrade with neoadjuvant chemotherapy?

Objective

Neoadjuvant chemotherapy (NC) is increasingly being used for large primary breast carcinomas with the aim of improving breast-conservation surgery (BCS) rates. This study was conducted to assess the tumour response following NC.

Methods

In this retrospective study over a 4-year period, 61 women with large operable invasive breast cancers (T_2–4 N_0–2 M₀), unsuitable for BCS, were consecutively treated with NC (5-FU, epirubicin, cyclophosphamide and Taxotere). Pathological response was monitored, comparing original core biopsy histology with final excisional histology.

Results

The mean age of patients was 48.6 years (range 30–70). Of the 61 patients, BCS was achieved in 48 (79%) patients. On the core biopsy, four (6.5%) patients had grade I cancer, 26 (43%) had grade II cancer and 31 (51%) had grade III cancer. Final histology showed no invasive cancer in eight (13%) patients (seven DCIS, and complete pathological response in one patient). In the rest of the patients, four (6.5%) had grade I tumours, 26 (43%) had grade II tumours and 23 (38%) had grade III tumours. Overall, 14 patients (23%) showed a decrease in histological grade (see Table 1). Seven patients (11.5%) had a higher grade than the initial core.

Table 1

Conclusion

In our series of patients receiving NC for breast cancer, there is not only a significant downsizing (permitting BCS) but also a trend of downgrading of the tumour, and this is seen particularly in poorly differentiated tumours. The higher grade on final histology compared with the core could be due to an unrepresentative core biopsy in large tumours prior to NC.