Accuracy of sentinel lymph node detection following intra-operative cervical injection for endometrial cancer: a prospective study.

OBJECTIVE

The objective of this study is to evaluate the detection rate and diagnostic accuracy of sentinel lymph node (SLN) mapping using intra-operative cervical injection of filtered 99mTc-sulfur colloid (99mTc-SC) and patent blue in patients with endometrial cancer.

METHODS

Prospective evaluation of the first 100 endometrial cancer patients undergoing SLN mapping using cervical injection of patent blue combined with filtered 99mTc-SC in the operating room was done. Patients underwent robotic-assisted lymphatic mapping with frozen section, hysterectomy, BSO, and completion bilateral lymphadenectomy (including para-aortic nodes in grade 2 and 3 tumors).

RESULTS

At least one SLN was detected in 92% of patients; in 66 of these (72%) bilateral SLN were detected, and in 15 cases the SLN was in the para-aortic area. Eleven percent of all patients had lymph node metastases, and 4 of which had pre-operative grade 1 tumor. The SLN was the only positive node in 44% of the cases with positive nodes. Sensitivity was 89% with 1 false negative result, yielding a negative predictive value of 99% (95% CI 93-100). Specificity was 100% (95% CI 94-100), and positive predictive value was 100% (95% CI 60-100). No complications or anaphylactic reactions were noted.

CONCLUSIONS

Intra-operative SLN biopsy, using cervical injection of patent blue and filtered 99mTc-SC in endometrial cancer patients is feasible and yields adequate detection rates.