[Sentinel lymph node for breast cancer: remove less to know more]

Our aim was to study the value of sentinel lymph node (SLN) biopsy in patients with breast cancer seen at a community hospital.

Consecutive cases receiving primary treatment for unicentric breast cancer less than 3 cm in diameter were prospectively studied from January 1999 to July 2000. All patients signed a detailed informed consent. The majority of patients (89%) underwent a combined technique of intradermal injection of 0.3-1.2 mCi of (99)Tc and 1-3 cc of Patent Blue at the biopsy site. Intraoperative localization was performed with a hand-held gamma probe. The first 15 patients underwent routine back-up lymphadenectomy. Thereafter, only patients with positive SLN, suspicious findings, or personal preference underwent formal axillary dissection.

One hundred eight cases were included in the study with a median age of 61 years and a median diameter of the breast tumor of 1.5 cm. Success rate for identification of SLN was 94% (101/108 cases). A total of 917 additional lymph nodes were removed after SLN biopsy (median 6.5 lymph nodes/patient). Correlation between SLN and the final axillary status was 98%. In 20/36 patients (61%) with positive axillary status the sentinel lymph node was the only positive one. Ten patients had only microscopic foci of cancer found in the SLN. Sixty-seven patients (62%) could have avoided axillary dissection becouse the SLN was found, it was negative, and there were no other intraoperative suspicious findings.

SLN biopsy is accurate and easily reproduced. Our data confirms that the majority of breast cancer patients may no longer need routine axillary lymphadenectomy.