Therapeutic effect of sentinel lymphadenectomy in T1 breast cancer.

OBJECTIVE

To evaluate whether the tumor status of the sentinel lymph node (SN) would alter the systemic adjuvant therapy administered to patients with T1 breast cancer.

DESIGN AND PATIENTS

Consecutive breast cancer patients (tumors < or = 2 cm) who underwent successful sentinel lymphadenectomy.

MAIN OUTCOME MEASURES

Metastatic tumor in the SN, primary tumor size, recommendations for systemic adjuvant therapy before and after histopathologic evaluation of the SN, and actual systemic adjuvant therapy received by the patient.

RESULTS

Of 142 total patients, 14 had T1a tumors; 35, T1b; and 93, T1c. Recommendations for systemic adjuvant therapy were initially determined solely by primary tumor characteristics and menopausal status. These recommendations were compared with recommendations for systemic adjuvant therapy based on tumor characteristics, menopausal status, and SN status; and then were compared with actual systemic adjuvant therapy received by the patient. Among the 118 patients with T1a, T1b, and favorable (positive estrogen or progesterone receptors and a low S-phase percentage with respect to DNA content) T1c tumors, 15 (37.5%) of 40 premenopausal patients and 20 (25.6%) of 78 postmenopausal patients became candidates for chemotherapy when examination of the SN revealed axillary metastasis; chemotherapy was actually administered to all 15 premenopausal patients but to only 6 postmenopausal patients. In the remaining 24 patients with unfavorable T1c tumors, SN status did not change the recommendation for chemotherapy but may have altered the choice of specific chemotherapeutic agents.

CONCLUSIONS

Identification of tumor-involved SN may alter systemic adjuvant therapy in patients with T1a, T1b, and favorable T1c tumors and may potentially change the type or dose of chemotherapeutic agents given to patients with unfavorable T1c tumors. Surgical axillary staging of the axilla remains an essential part of breast cancer management and should not be abandoned.