Sentinel lymph node mapping for early-stage cervical cancer: A single institution's experience

Abstract

Objectives: Lymph node assessment remains a key part of surgical evaluation for patients with early-stage cervical cancer, and provides important prognostic information to determine appropriate adjuvant therapy. We aim to compare our experience with sentinel lymph node (SLN) mapping in patients with early-stage cervical cancer with a historical cohort of patients at our institution. Methods: We searched an institutional database for patients with cervical cancer between 1982 and 2014. Pertinent clinical and pathologic data were abstracted from the medical records. A historical cohort included patients from 1982 to 2009 who underwent selective lymph node (LN) sampling. An SLN mapping algorithm was performed according to institutional protocol in a cohort of patients from 2005 to 2014 (SLN cohort). Isolated tumor cells, micrometastases, and macrometastases were considered positive. Only patients with stage IB1 or IB2 squamous cell carcinoma or adenocarcinoma of the cervix were included. Appropriate statistical tests were performed. Results: We identified 531 patients with cervical cancer who underwent surgical evaluation at our institution: 123 (23.2%) patients in the SLN cohort and 408 (76.8%) in the historical cohort. Median of the 2 groups was similar (SLN: median 36.5 years, range 20–77 years; historical cohort: median 40 years, range 20–92 years; P = .052). Most patients had stage IB1 disease (91.1% in the SLN and 90.4% in the historical cohort). More patients in the historical cohort had squamous cell carcinoma (43 [35%] in the SLN vs 208 (51%) in the historical cohort, P = .002). Patients received adjuvant radiation at a similar rate in both groups (28.5% in the SLN vs 27.2% in the historical cohort, P = .05). Fewer LNs were removed (19 [range, 2–70] vs 27 [range, 1–80], P < .0001) and more positive LNs were detected in the SLN cohort (23 [18.7%] vs 51 [12.5%], P = .03]. Median follow-up was similar between the 2 groups (51.6 months [range, 0.5–109] in the SLN vs 56.5 months [range, 1.0–338.8], P = .22 in the historical cohort). Median recurrence-free (RFS), disease-specific (DSS), and overall survival (OS) was not reached in either group. Five-year RFS (100% vs 93.1% ± 1.4%, P = .006), DSS (97.7% ± 1.6% vs 91.3% ± 1.6%, P = .047), and OS (95.1% ± 2.2% vs 87.2% ± 1.8%, P = .027) were greater in the SLN cohort. Conclusions: Patients undergoing SLN mapping have fewer total LNs removed but a higher detection rate of positive LNs compared with a historical cohort. In this single institution comparison, SLN mapping did not compromise the detection of positive LNs or outcome of patients with squamous cell or adenocarcinoma of the cervix.