Commentary (Kavanagh): Sentinel Node Evaluation in Gynecologic Cancer

It is generally accepted that lymph node status is one of the most important prognostic factors in vulvar and cervical carcinoma.[4,5] The problematic area has remained the long-standing practice of evaluating lymph node status by complete or near-complete lymph node resections followed by pathologic evaluation. It is clear that extensive lymph node dissection adds to morbidity and increases the complications of radiation therapy.[6-10] Because anatomists have felt that lymph node drainage is predictable but not uniform, identification of the "first leve" lymph node as the gatekeeper or indicator of subsequent metastatic disease would be most useful. This concept has led to the term "sentinel node," which was first applied in the setting of penile cancer, as identified by lymphangiogram.[11] Such a node would enable us to predict the probability of metastatic disease beyond that node. This is assumed to be information of adequate independent prognostic value to alter effective subsequent therapies. The review of sentinel node evaluation in gynecologic cancer by Marie Plant et al provides a well-balanced and cautious overview of this technology. Indeed, it is difficult to be very critical of this paper when the concluding statements call for more data before these techniques can become a standard of care. The focus of my discussion will be more on emphasizing the unresolved issues of sentinel node evaluation.