Sentinel lymph node biopsy in the treatment of breast cancer. Experience in 527 cases

Knowledge of axillary lymph node status is a key aid to staging and prognosis and it represents a guideline for adjuvant therapy in breast cancer. Despite the morbidity it causes, complete axillary dissection was long the mainstay of treatment. Sentinel lymph node biopsy has proved so reliable in the evaluation of node involvement that axillary node dissection is now generally performed when sentinel node biopsy tests negative.

In this 3-phase study, 50 patients were enrolled to evaluate the learning curve of sentinel node biopsy (phase 1, September 1997-January 1998); 256 patients (age range 27-81 years) with infiltrative breast cancer (T <3 cm, clinical N0) underwent level 1 lymph node dissection when the sentinel node tested negative at histopathology (phase 2, February 1998-March 2001); 221 patients with T <3 cm underwent dissection of the sentinel node when it tested negative for metastasis (phase 3, April 2001-March 2005).

The sentinel node was preoperatively detected in 98.6% of cases after peritumoral and intradermic injection of the radionuclide tracer and intraoperatively in 99% (90% with radio-guided surgery, 10% with vital staining). The sentinel node was positive in 15% of patients with T1 and metastatic in 65%.

Our results are in line with the published data; therefore, the study will go forward to examine the role of the micrometastasis in the sentinel node and of in-transit tumoral cells.