Histopathological validation of the sentinel node concept in cervical cancer

Background: The sentinel node (SN) is defined as the first node in the lymphatic system that drains a tumor site. If the SN is not metastatic, then all other nodes should also be disease-free. We used serial sections and immunohistochemical (IHC) staining to examine both sentinel and non-sentinel nodes (non-SNs). Materials and methods: From July 2001 to March 2003, 18 patients (median age, 48 years) with cervical cancer (stage IA2, one patient; stage 113 1, nine patients; stage 1132, three patients; stage IIA, three patients; and stage 1113, two patients) underwent a laparoscopic SN procedure based on a combined detection method, followed by complete laparoscopic pelvic lymphadenectomy. If the SN was free of metastasis by both hematoxylin and eosin (H&E) and IHC staining, all non-SNs were also examined by the combined staining method. Results: A mean of 2.4 SNs (range 1-5) and 8 non-SNs (range 4-14) were excised per patient. Eight SNs (18.2%) from five patients (27.8%) were found to be metastatic at the final histological assessment, including two macrometastatic SNs, three micrometastatic SNs and isolated tumor cells in three SNs. In 13 patients, no metastatic SN involvement was detected by H&E and IHC staining. In these 13 patients, 106 non-SNs were examined by serial sectioning and IHC, and none was found to be metastatic. Conclusions: The SN procedure appears to reliably predict the metastatic status of the regional lymphatic basin in patients with cervical cancer.