Sentinel lymph node biopsy: technique validation at the Setúbal Medical Centre, Portugal

Area of Science:

• Oncology
• Surgical Pathology
• Nuclear Medicine

Background:

• Accurate staging of axillary lymph nodes is crucial for breast cancer treatment.
• Sentinel lymph node biopsy (SLNB) offers a less invasive alternative to axillary lymph node dissection (ALND).

Purpose of the Study:

• To evaluate the diagnostic accuracy of SLNB in breast cancer patients.
• To validate the use of combined technetium-99m sulphur colloid and patent blue vital dye for SLNB at this institution.

Main Methods:

• Fifty early breast cancer patients with clinically negative axillae underwent SLNB using (99m)Tc sulphur colloid and patent blue dye.
• Sentinel nodes were identified intraoperatively using a gamma probe and visual inspection.
• Pathological analysis included frozen section, H&E staining, and immunohistochemistry, compared with ALND findings.

Main Results:

• SLN identification rate was 96% (48/50 patients).
• The sensitivity of SLNB in predicting axillary status was 93.75%, with an overall accuracy of 97.96%.
• A false-negative rate of 6.25% was observed in successfully identified SLNs.

Conclusions:

• SLNB is an accurate and minimally invasive method for staging axillary lymph nodes in early breast cancer.
• The combined radiotracer and vital dye technique is effective and reliable.
• SLNB can be adopted as the standard staging procedure for eligible breast cancer patients at this institution.