Tanaka 18_10

A sentinel node biopsy (SNB) has been proved to be an accurate method to estimate the axillary lymph node status as a replacement for axillary lymph node dissection (AxLND) in patients with early breast cancer who have not been treated with neoadjuvant chemotherapy (NAC). We examined the feasibility and accuracy of performing SNB after NAC. Seventy breast cancer patients treated with NAC were enrolled in the current study during the period between March 2001 and June 2005. NAC performed preoperatively consisted of three to four times of CAF chemotherapy. Moreover, intra-arterial (subclavian artery and internal mammary artery) infusion of epirubicin and 5-fluorouracil was performed in addition to systemic CAF chemotherapy once to three times in patients with large breast tumors or bulky axillary lymph node metastases. The sentinel nodes were successfully identified in 63 out of 70 patients (identification rate: 90%). The mean number of sentinel nodes removed per patient was 1.5 (range 1-6). Of the 43 patients in whom AxLND was performed after the sentinel nodes were identified, 19 (44.2%) had positive sentinel nodes. In 8 of those 19 patients, the sentinel node was the only cancer positive lymph node. Among the 24 patients who had negative sentinel nodes it was found that one patient had a confirmed false negative result, thus yielding a false negative rate of 5%, and a sensitivity of 95%. There was no false negative patient who had a clinically negative lymph node status (N0) before NAC (17 patients), whereas the false negative rate was 6.3% in the subgroup of patients with a clinically positive lymph node status (N1, N2) before NAC (26 patients). As a result, SNB after NAC is thus considered to be able to effectively predict the axillary lymph node status in patients with a clinically negative lymph node status before NAC. Introduction Axillary lymph node dissection (AxLND) has been routinely performed in breast cancer operations, because the regional lymph node status is known to be the most important prognostic factor in breast cancer, as well as being an important decision factor in selecting the optimal postoperative adjuvant therapy. However, there is no evidence that AxLND improves the prognosis of breast cancer patients, and the main therapeutic role of AxLND is thus considered to be to achieve axillary local control. A sentinel node biopsy (SNB) has been rapidly introduced in many institutes to determine the staging for the axilla of breast cancer patients who were supposed to have no axillary lymph node metastasis as a replacement for AxLND which is associated with a higher morbidity than SNB. Patients who showed a complete pathological response (pCR) after neoadjuvant chemotherapy (NAC) proved to have an excellent prognosis (1). As a result the number of institutes that use NAC is increasing. The biggest advantage of NAC is to clarify the cancer characteristics of sensitivity to anti-cancer agents in vivo, which is valuable information for selecting the optimal anti-cancer agents for each breast cancer patient. In this context, SNB after NAC may thus enable us to avoid AxLND in cases that positively respond to NAC. However, in patients treated with NAC, SNB has not been recognized as a replacement for AxLND, because NAC may affect the lymphatic drainage and therefore hamper sentinel node detection. There is still limited information on the feasibility and accuracy of SNB after NAC. The objective of the current study was to investigate the feasibility and accuracy of SNB in patients with breast cancer who were treated with NAC in our series. Patients and methods Seventy patients with breast carcinoma who had been treated with NAC were enrolled in the current study during the period between March 2001 and June 2005. NAC was performed preoperatively and consisted of three to four times of CAF chemotherapy (each chemotherapy administration consisted of 600 mg/m2 of cyclophosphamide, 600 mg/m2 of 5-fluorouracil, and 20-40 mg/body of pirarubicin, every two weeks) (2). ONCOLOGY REPORTS 15: 927-931, 2005 927 Sentinel node biopsy in breast cancer patients treated with neoadjuvant chemotherapy YOSUKE TANAKA1, HIRONORI MAEDA2, YASUHIRO OGAWA3, AKIHITO NISHIOKA3, SATOSHI ITOH3, KEI KUBOTA3, HIRONOBU UE3, KIMIKO NAKATANI3 and SHIRO SASAGURI2 1Operation Center, and Departments of 2Surgery II and 3Radiology, Kochi University Hospital, Kochi Medical School, Kochi University, Japan Received October 18, 2005; Accepted December 22, 2005 _________________________________________ Correspondence to: Dr Yosuke Tanaka, Operation Center, Kochi University Hospital, Kochi Medical School, Kochi University, Oko-cho, Nankoku-shi, Kochi-Prefecture 783-8505, Japan E-mail: [email protected]