SLN biopsy in cervical cancer patients with tumors larger than 2cm and 4cm

The aim of this study was to assess the detection rate, false-negative rate and sensitivity of SLN in LN staging in tumors over 2cm on a large cohort of patients.

Data from patients with stages pT1a - pT2 cervical cancer who underwent surgical treatment, including SLN biopsy followed by systematic pelvic lymphadenectomy, were retrospectively analyzed. A combined technique with blue dye and radiocolloid was modified in larger tumors to inject the tracer into the residual cervical stroma.

The study included 350 patients with stages pT1a - pT2. Macrometastases, micrometastases, and isolated tumor cells were found in 10%, 8%, and 4% of cases. Bilateral detection rate was similar in subgroups with tumors<2cm, 2-3.9cm, and ≥4cm (79%, 83%, 76%) (P=0.460). There were only two cases with false-negative SLN ultrastaging for pelvic LN status among those with bilateral SLN detection. The false negative rate was very low in all three subgroups of different tumor sizes (0.9%, 0.9%, and 0.0%; P=0.999). Sensitivity reached 96% in the whole group and was high in all three groups (93%, 93%, 100%; P=0.510).

If the tracer application technique is adjusted in larger tumors, SLN biopsy can be equally reliable in pelvic LN staging in tumors smaller and larger than 2cm. The bilateral detection rate and false negative rate did not differ in subgroups of patients with tumors<2cm, 2-3.9cm, and ≥4cm.