Sentinel lymph node biopsy without axillary dissection after an intraoperative negative histological investigation in 358 invasive breast cancer cases

BACKGROUND: Sentinel lymph node biopsy (SLNB) is an important treatment option for breast cancer patients, as it can accurately predict axillary status. Our previous study using dye with or without radioisotope showed the accuracy and sensitivity of SLNB to be 97% and 94%, respectively. Based on these results, axillary lymph node dissection (ALND) was eliminated starting in January, 1999 in patients with intraoperatively negative SLNB at our institution. The present study shows the results and outcomes of SLNB as a sole procedure for patients with invasive breast cancer. PATIENTS AND METHODS: Three-hundred-fifty-four patients and 358 cases of invasive breast cancer (4 bilateral breast carcinoma) treated with SLNB alone after an intraoperative negative SLNB were studied prospectively from January 1999 to December 2001. RESULTS: The number of the identified SLNs per case ranged from 1 to 8 (mean, 2.5). Of a total of 358 cases, 297 (83%) were treated with hormone therapy and/or chemotherapy, and 281 (78%) were treated with radiotherapy to the conserved breast (50 Gy+/-10 Gy boost), the axilla (50 Gy), or the both sites. After a median follow-up of 21 (range 6-42) months, no patient developed an axillary relapse. Four cases initially recurred in distant organs and one case in the conserved breast. CONCLUSIONS: Our results indicate that an intraoperative negative SLNB without further ALND may be a safe procedure when strict SLNB is performed. To better assess the safety, however, may require longer follow-up.