Objective: To compare the incidence of pelvic lymph node metastases in early stage cervical cancer patients undergoing sentinel lymph node biopsy (SLN) to a matched cohort undergoing pelvic lymphadenectomy.
Methods: All patient data were entered prospectively into an ongoing cervical cancer database. Since April 2004, 87 patients with FIGO stage IA/B1 cervical cancer underwent SLN detection with identification of bilateral SLN. This cohort (cases) was compared to a matched group of patients who underwent complete pelvic lymphadenectomy (controls). The groups were matched 3:1 for tumour size (+/-5 mm), histology, depth of invasion (+/-2 mm), and presence of capillary lymphatic space invasion (CLS). Descriptive statistics were calculated for all variables of interest. The association between cases and controls and lymph node metastases was carried out using a conditional logistic regression analysis.
Results: 81 women in the SLN cohort were matched with 1 control, 72 cases with 2 controls, and 65 cases with 3 controls. Among cases, 14 (17%) had pelvic lymph nodes metastases vs. 15 (7%) in the controls (p=0.0059, odds ratio= 2.8, 95% CI=1.3-5.9). Among the 14 cases of SLN metastases, 11 were detected by frozen section and 3 were detected on final paraffin sectioning. All were detected by H and E stains. The size of the SLN metastases ranged from less than 1 mm to 8 mm.
Conclusions: Sentinel lymph node biopsy in early cervical cancer is a more sensitive procedure in detecting pelvic lymph node metastases compared to complete lymphadenectomy.