Controversies in Sentinel Lymph Node Biopsy for Gynecologic Malignancies

Abstract

Objective: Sentinel lymph node (SLN) biopsy represents an evolution in the advancement of minimally invasive surgical techniques for gynecologic cancers. Prospective and retrospective studies have consistently shown its accuracy in the detection of lymph node metastases for endometrial and cervical cancers. However, consistent with any emerging surgical technique in the early phases of adoption, new questions have arisen regarding its application and impact. This paper served as a scoping review to identify the key controversies that have arisen in the field of SLN biopsy for endometrial and cervical cancers.

Data sources: Several key controversies were identified, and PubMed, the Cochrane Library (cochranelibrary.com) advanced search function, and the National Comprehensive Cancer Network guidelines were searched for supporting evidence. These included search terms such as "the accuracy of SLN biopsy for high grade endometrial cancer or cervical cancers >2-cm," "cost effectiveness of SLN biopsy for gynecologic cancers," "clinical significance of low volume metastases in endometrial cancer," "morbidity of SLN biopsy for endometrial and cervical cancer," and "impact on cancer survival of SLN biopsy for endometrial and cervical cancer."

Methods of study selection: Studies were selected for review if they included significant numbers of patients, were level I evidence, or were prospective trials. Where this level of evidence failed to exist, seminal observational series that were published in high-quality journals were included.

Tabulation, integration, and results: Similar studies were listed and subcategorized and cross-compared, excluding those that included repeated analyses of the same patient populations. The relevant clinical trials or observational studies were clustered and reviewed for each chosen controversy. Adequate evidence supports the accuracy of SLN biopsy in the staging of high-grade endometrial cancer and cervical cancer, and it seems to be a cost-effective strategy for invasive endometrial cancer. Conclusive evidence was lacking with respect to the oncologic outcomes related to SLN biopsy, the impact on patient morbidity, and whether clinicians should treat isolated tumor cells in SLNs with adjuvant therapy.

Conclusion: SLN biopsy is an accepted staging strategy for cervical and endometrial cancer surgery; however, controversies remain in how it can be applied with the most safety and efficacy. These ultimately need to be resolved with further clinical trials and observations of larger series of patients.

Keywords: Cervical; Endometrial; Sentinel node biopsy.