A systematic review of the accuracy of diagnostic tests for inguinal lymph node status in vulvar cancer.

OBJECTIVE: To determine the accuracy of minimally and non-invasive tests to assess the groin node status in squamous cell vulvar cancer.
METHODS: A systematic review of published research from 1979 to 2004 that compares the results of tests to determine groin node status with histology at inguinofemoral lymphadenectomy was made. Studies included in the review were those that compared the index test to the standard surgical intervention of inguinofemoral lymphadenectomy and allowed the construction of two-by-two tables. From these tables, sensitivity, specificity, and the likelihood ratios (with 95% confidence intervals) were reported and, where feasible, meta-analysis was used to pool results for each test separately. Sentinel node biopsy using technetium-99m-labelled nanocolloid ((99m)Tc) had a pooled sensitivity and negative LR of 97% (91-100 95% CI) and 0.12 (0.053-0.28 95% CI), respectively, and was the most accurate test reviewed.
CONCLUSION: Five diagnostic tests were identified in a total of 29 studies (961 groins). Although the studies were small and the design often poor, this represents the best summary of the data to date. Sentinel node identification using (99m)Tc appeared to be the most promising test for accurately excluding lymph node metastases in squamous cell vulvar cancer and potentially reducing the radicality of surgery. Its efficacy as a tool in reducing the need for radical surgery and associated patient morbidity without reducing survival needs further assessment probably in a randomised control trial.