Identification of the sentinel lymph node stained with blue dye in breast cancer patients

This study aimed to evaluate the reproducibility of sentinel lymphadenectomy in breast cancer patients (T1N0M0 and T2N0M0) and its possibility of predicting the total axillary behavior.

A total of 25 patients were evaluated, all presenting palpable mammary nodes between 1.5 and 5 cm (T1 and T2), with clinically negative axillary lymph nodes (N0). After an incisional biopsy of the tumor and histopathological confirmation of invasive breast carcinoma, a study of the sentinel lymph node took place with a peritumoral injection of 4 ml of blue dye at 2.5%. After waiting for 15 to 20 minutes, a search for the blue stained lymphatic vase in the axillary fat was carried out, which would lead to the sentinel lymph node, stained or not. At that point, a mastectomy (20 patients) or a quadrantectomy (5 patients) was performed, both with axillary lymphadenectomy at grades 1, 2 and 3. The sentinel lymph nodes and the material from the axillary dissection were sent separately for an anatomicopathological test in paraffin.

The lymph nodes were identified in 19 patients, which represented a 76% detection rate. There was a concordance between the sentinel lymphadenectomy and the standard axillary dissection in 68.4% of the patients. The false-positive and the false-negative rates observed were 10% and 55.5%, respectively. A higher detection rate was found in tumors larger than 2 cm and situated in external quadrants.

Sentinel lymphadenectomy identified the sentinel lymph node in the majority of the patients in this study, although the high rate of false-negatives observed prevented an accurate staging.