[Sentinel node biopsy for breast cancer patients at the Bács-Kiskun County Teaching Hospital]

Abstract

Introduction: The optimal technique of sentinel node biopsy (SNB) is still debated.

Aims: To compare two methods of SNB, describe the learning phase, the validation of the methods and the first results after implementing SNB as standard of care in selected breast cancer patients.

Patients and methods: SNB with peritumoral or intratumoral injection of Patent blue dye only was performed in 129 clinically T1-T2 and N0 breast cancers in 127 patients (Group A); it was later replaced by combined dye and radiocolloid-guided SNB preceded by lymphoscintigraphy in 72 breast cancer patients (Group B). All patients underwent completion axillary dissection. Group C, to date, comprises 50 patients, in whom axillary dissection was performed on the basis of the SNB. Intraoperative imprint cytology was performed, and whenever positive, the axillary dissection was completed in the same step, whereas in cases of negative cytology findings but positive final histology, the dissection was done as a second operation. Histopathological assessment of SNs involved step sectioning and immunohistochemistry.

Results: Means of 1.4 and 1.3 SNs were identified in Groups A and B, respectively. The mean number of non-SNs for the whole series was 14.7 (range 5-42). The first 53 cases of lymphatic mapping with patent blue dye comprised the institutional learning period, during which the identification rate of at least 1 SN in 30 consecutive attempts reached 90%. The identification rate for the subsequent 76 Group A patients was 92%. The accuracy of SNB for overall axillary nodal status prediction and the false-negative rate for Group A patients (after exclusion of the learning-phase cases) were 93% and 10%, respectively. All 72 Group B cases had at least 1 SN identified, and only 1 false-negative case occurred in this group, i.e. the accuracy and false-negative rate were 99% and 3%, respectively. The identification rate in Group C was 98%; axillary dissection could be avoided in 25 patients, it was performed at the same time as the SNB in 15 and as a second operation in 10. Till now, no axillary recurrence was detected in Group C patients, although the follow-up period is short for the moment.

Conclusions: The dye only and the radioguided SNB methods are complementary, their combination improves the performance, and can be the basis of performing axillary dissection on the basis of SNB results. After the technique of SNB has been validated in a given institution, it can become standard of care in a well selected group of patients, but requires a close follow up.