Purpose: To evaluate remission and breast-conservation rates after preoperative chemotherapy or chemo-radiotherapy (CT-RT).
Patients and methods: Seventy-three patients with 74 biopsy-proven invasive breast cancers prospectively entered the protocol. Eighteen patients were treated by neoadjuvant chemotherapy followed by surgery and adjuvant irradiation (chemotherapy group). Fifty-five patients with 56 tumors were treated with combined neoadjuvant chemo-radiotherapy, followed by surgery (chemo-radiotherapy group). Most patients of both treatment groups received 4 cycles of EC chemotherapy. In some patients with large tumors 3 cycles of CMF were added. Chemotherapy was followed by hormonal treatment with tamoxifen or LHRH agonists in case of positive hormone-receptor status. Preoperative radiotherapy was administered using 2 Gy fractions up to a total dose of 50 Gy, followed by a tumor boost of 6 to 11 Gy. The median overall treatment time was 41 days (range: 35 to 55 days). The median time interval between end of neoadjuvant therapy and surgery was 11 weeks (range: 10 to 22 weeks) and 27 weeks (range: 11 to 41 weeks) for the chemotherapy- and chemo-radiotherapy group. The median time interval between end of chemotherapy and the beginning of irradiation ranged between 2 and 8 weeks (median 4 weeks) in the chemo-radiotherapy group.
Results: Side-effects due to chemo- or radiotherapy were moderate and reversible. In the chemotherapy group 17/18 patients (94%) achieved a partial (pPR) and 1/18 patients (6%) a complete histopathological response (pCR). In the chemo-radiotherapy group 32/56 (57%) showed a pPR and 24/56 (43%) a pCR. The difference in complete remission is significant (Fisher's Exact Test: p = 0.004). In 45/74 cases (61%) the breast was preserved, immediate breast reconstructions with rectus myocutaneous flaps (TRAM) after mastectomy were performed in 8/74 cases (11%) and modified radical mastectomies without reconstruction were required in 21/74 cases (28%). The breast conservation rates were similar in both treatment groups.
Conclusions: Even though the small number of patients in the present protocol does not permit definite conclusions, the results of combined modality treatment seem promising with regard to tumor remission within the treated breast and as a tool for breast conservation in advanced stage disease. On the basis of these encouraging data a prospective Phase-III study has been initiated.