[Detection of sentinel lymph node in patients with breast cancer]

To evaluate the technique and significance of the sentinel lymph node (SLN) biopsy using different methods in patients with breast cancer.

Seventy-one female patients with node-negative breast cancer diagnosed by fine needle biopsy or frozen section underwent lymphatic mapping. They were divided into 4 groups: methylene blue, isosulfan blue, (99m)technetium-labelled sulfur colloid, combined vital blue dye and radiocolloid. The number of each group was 24, 29, 8 and 10 respectively. The SLN was identified and removed, followed by a definitive cancer operation, including a complete axillary node dissection. Pathological examination of the SLN was made with HE and immunohistochemical staining. Pathologic characteristics of SLN and other axillary nodes were analyzed.

Among the 71 patients, 60 were (84.5%) confirmed by SLN biopsy. The positive rates were 75.0% (18/24) for methylene blue group and 86.2% (25/29) for isosulfan blue group, respectively. Seven positive cases were detected by (99m)technetium-labelled sulfur colloid and all the positive cases by combined vital blue dye and radiocolloid. The total sensitivity was 83.3% and the sensitivity for each group was 70.0%, 90.0%, 100% and 100%, respectively. The total false negative rate was 16.7% and the false negative rate for each group was 30.0%, 10.0%, 0 and 0, respectively. The total accuracy rate was 93.3% and the accuracy rate for each group was 83.3%, 96.0%, 100% and 100%, respectively. The time of finding the SLN was 29, 22, 7, 6 min respectively.

SLN biopsy is technically possible in patients with breast cancer. Most of SLNs can probably reflect the histological characteristics of the axillary lymph nodes. Combination of vital blue dye and isotope makes mapping exact and satisfactory and it may be the best choice among the four methods.