Laparoscopic sentinel lymph node mapping for cervix cancer--a detailed evaluation and time analysis.

Objective: To provide data from a US center on laparoscopic (LSC) approach to sentinel lymph node (SLN) detection in cervix cancer with detailed time analysis.

Methods: This prospective trial enrolled patients with stage IA2-IIA cervix cancer undergoing primary radical surgery. Tc-99 radiocolloid was injected the morning of surgery, followed by hybrid SPECT/CT lymphoscintigraphy. Blue dye injection occurred just prior to incision. After bilateral LSC SLN detection, all patients received complete LSC pelvic lymphadenectomy. Institutional SLN protocol was followed for frozen section, hematoxylin and eosin, and cytokeratin staining.

Results: Between December 2003 and February 2006, 20 enrolled patients received 9 LSC-assisted radical vaginal hysterectomies, 7 radical abdominal hysterectomies, 2 LSC-assisted radical vaginal trachelectomies, and 2 LSC lymphadenectomies alone (secondary to positive lymph nodes). Mean tumor size was 2.5 cm. Nineteen percent of the 64 SLNs were found in unusual sites, including common iliac (11%), presacral (5%) and para-aortic (3%). The negative predictive value was 100%. The combined technique detected SLNs bilaterally in all patients. If blue dye alone was used, this rate would have dropped to 67.5% and was negatively correlated with elapsed surgical time (-0.7; p=0.002). The ability to visualize blue SLNs remained steady for 30 min and was completely gone by 50 min.

Conclusions: Laparoscopic SLN mapping can be newly introduced into gynecologic oncology centers with high detection rates and negative predictive values. The visualization of blue dye in SLNs is transient, and this negative time correlation may explain the previously reported inferior detection rates with this technique. CLINICAL TRIAL REGISTRATION.: ClinicalTrials.gov, http://www.clinicaltrials.gov, NCT 00205010.