RESUMO
<p><b>OBJECTIVE</b>To study intra-operative radionuclide lymphatic mapping in sentinel lymph node (SLN) biopsy of breast cancer.</p><p><b>METHODS</b>Forty-two breast cancer (diameter </= 5.0 cm) patients with clinically negative axillary node were analyzed. 18.5 MBq/0.5 ml technetium-99m labeled sulfur colloid (labeling yield > 98%, size of colloid granule 100 approximately 200 nm) was injected into the mammary tissue around the tumor or biopsy site at four points. SLN in breast cancer was detected and dissected with the help of lymphoscintigraphy and intra-operative gamma probe. Routine lymph node dissection was performed for all patients.</p><p><b>RESULTS</b>The detection rate was 88.1% in lymphoscintigraphy and 97.6% in intra-operative gamma probe detection for SLN in breast cancer. The sensitivity, accuracy, false negative and specificity of SLN biopsy were 93.3% (14 in 15), 97.6% (40 in 41), 6.7% (1 in 15) and 100% (26 in 26).</p><p><b>CONCLUSION</b>Sentinel lymph node in breast cancer, detected by preoperative lymphoscintigraphy combined with intra-operative gamma probe, is able to predict regional lymph node metastasis. The successful rate of SLN biopsy can be raised by improvement in the quality of nuclear imaging agent, technic of injection and method of measurement.</p>