Sentinel Lymph Node and Breast Cancer Staging: Final Results of the Turin Multicenter Study

The false-negative rate of sentinel node biopsy in patients with breast cancer: a meta-analysis

BACKGROUND

In sentinel node surgery for breast cancer, procedural accuracy is assessed by calculating the false-negative rate. It is important to measure this since there are potential adverse outcomes from missing node metastases. We performed a meta-analysis of published data to assess which method has achieved the lowest false-negative rate.

METHODS

We found 3,588 articles concerning sentinel nodes and breast cancer published from 1993 through mid-2011; 183 articles met our inclusion criteria. The studies described in these 183 articles included a total of 9,306 patients. We grouped the studies by injection material and injection location. The false-negative rates were analyzed according to these groupings and also by the year in which the articles were published.

RESULTS

There was significant variation related to injection material. The use of blue dye alone was associated with the highest false-negative rate. Inclusion of a radioactive tracer along with blue dye resulted in a significantly lower false-negative rate. Although there were variations in the false-negative rate according to injection location, none were significant.

CONCLUSIONS

The use of blue dye should be accompanied by a radioactive tracer to achieve a significantly lower false-negative rate. Location of injection did not have a significant impact on the false-negative rate. Given the limitations of acquiring appropriate data, the false-negative rate should not be used as a metric for training or quality control.

Technical Advances in Sentinel Lymph Node Biopsy for Breast Cancer

Technical advances in the past several years have simplified and improved sentinel lymph node (SLN) biopsy for breast cancer. The use of alternative injection sites (skin or subareolar) yields high SLN identification rates and may shorten the learning curve associated with standard peritumoral injection. The dual-agent (radiocolloid plus blue dye) technique is now recommended to decrease false-negative rates, especially when surgeons are just learning how to perform SLN biopsy. Methylene blue may be an acceptable substitute for isosulfan blue dye and is associated with fewer hypersensitivity reactions. Hand-held gamma probes are now smaller and more maneuverable, with better shielding for directional detection of gamma rays. Routine preoperative lymphoscintigraphy can be avoided, thus facilitating operating room scheduling. Surgeons can use minimally invasive techniques to identify and remove internal mammary SLNs.

Utility of breast sentinel lymph node biopsy using day-before-surgery injection of high-dose 99mTc-labeled sulfur colloid

BACKGROUND

In sentinel lymph node (SLN) biopsy for breast cancer, many centers use same-day preoperative injection of technetium 99mTc-labeled sulfur colloid and intraoperative injection of blue dye for localization of SLNs. Same-day sulfur colloid injections can be problematic because of the variability in sulfur colloid migration times, which can lead to ineffective use of operating room time, and low SLN-to-background radioactivity ratios. We examined the utility of day-before-surgery injections of high dose 99mTc-labeled sulfur colloid injections.

METHODS

The day before surgery, high-dose 99mTc-labeled sulfur colloid was injected peritumorally, and a lymphoscintigram was obtained. Intraoperatively, after injection of blue dye, a gamma probe was used to localize SLNs. Nodes that were stained blue or were highly radioactive were considered SLNs and were removed.

RESULTS

Lymphoscintigraphy demonstrated drainage in 107 patients (91%). Transcutaneous localization of the SLN was possible in 104 patients (89%). In three patients, all of whom had no drainage demonstrated on lymphoscintigraphy, no SLN was identified at surgery (97.5% success rate for SLN identification). A mean of 2.3 SLNs per patient were identified. Twenty-five patients (21%) had at least one histologically positive SLN. In 23 of these patients, the positive SLN was the SLN with the most radioactivity, and in the remaining two patients, the positive SLN was both blue-stained and hot.

CONCLUSION

Day-before-surgery injection of high-dose 99mTc-labeled sulfur colloid results in high rates of transcutaneous and intraoperative identification of SLNs. The delay between injection and surgery did not appear to promote significant passage of sulfur colloid to second-echelon nodes.