Removal of all radioactive sentinel nodes in breast cancer improves the detection of positive sentinel nodes.

OBJECTIVE

The aim of this study is to evaluate if it is necessary to remove all the radioactive sentinel lymph nodes (SLNs) not seen on lymphoscintigraphy in order to accurately stage breast cancer patients.

MATERIAL AND METHODS

From March 1999 to March 2006, SLN biopsy was performed in 461 patients. All patients were only injected with radioisotope. Lymphoscintigraphy was performed in all the patients. The mean number of SLNs removed was 2.1 (range 1-15).

RESULTS

The SLN was positive in 133 patients (28.8%). Lymphoscintigraphy accurately predicted the number of SLNs identified intraoperatively in 243 patients (52.7%). In 175 patients (37.9%) there were more SLNs identified intraoperatively than were seen on lymphos cintigraphy. In 11 (6.2%) of these 175 patients, additional SLNs identified intraoperatively harboured metastasis. Type of injection, need for a second injection, tumour location and age were not identified as statistically significantly associated with additional positive SLNs identified intraoperatively and not seen on lymphoscintigraphy.

CONCLUSIONS

Lymphoscintigraphy does not accurately predict the number of SLNs identified intraoperatively, this number being underestimated. Surgeons should remove all radioactive SLNs to improve the detection of positive SLNs.