The detection of sentinel nodes in ovarian cancer: a feasibility study

Few sentinel node (SN) studies in ovarian cancer have been reported, mainly because of the risk of tumor dissemination associated with the injection of tracers into the ovarian cortex. To our knowledge, the injection of tracers into the ovarian ligaments has not been explored. The aim of this study was to determine the feasibility of the SN procedure in ovarian cancer with tracer injection into the ovarian ligaments and to establish whether the procedure is safe for the healthcare workers.

Methods: The study included patients who were at high risk of ovarian malignancy. Blue dye and radioactive colloid were injected into the proper ovarian ligament and suspensory ligament of the ovary. To measure professional radiation exposure, ring dose meters were worn by the surgeon, theater nurse, and pathologist during 3 procedures.

Results: An SN procedure was performed in 21 patients, and at least 1 SN location was identified in all patients using the γ probe before retroperitoneal exploration. SNs were located in the paraaortic and paracaval regions only in 67% of the patients, in the pelvic region only in 9%, and in both the paraaortic/paracaval and the pelvic regions in 24%. All but 2 SNs were found on the ipsilateral side. In 6 patients who underwent retroperitoneal exploration, 1-4 SNs were identified using the γ probe and resected. Blue-stained SNs were detected in 2 patients. Positive SNs were detected in 1 patient with lymph node metastases. The amount of radiation exposure to the surgeon, theater nurse, and pathologist did not exceed the safe limit.

Conclusion: The identification of SNs in all cases suggests that the SN procedure performed by injection of tracers in the ovarian ligaments is feasible and promising. The procedure is safe for the involved personnel. Further investigation is necessary to determine the clinical application of this new technique.