Sentinel node detection with ^99mTc phytate alone is satisfactory for cervical cancer patients undergoing radical hysterectomy and pelvic lymphadenectomy

Background: If the sentinel-lymph-node (SLN) concept is valid in cervical cancer, most patients could avoid pelvic lymphadenectomy when absence of metastasis is intraoperatively confirmed in the SLN. We assessed feasibility and accuracy of SLN detection using ^99mTc phytate in patients with cervical cancer. Methods: Eighty-two women with stage Ia-IIb cervical cancer enrolled in this study. All underwent hysterectomy or trachelectomy with accompanying total pelvic lymphadenectomy. On the day before surgery, we injected fluid containing ^99mTc-labeled phytate subepithelially into four cervical quadrants outside the tumor. Intraoperatively, SLNs were identified as radioactive "hot nodes" by gamma probe. Systematic bilateral pelvic lymphadenectomy was performed after the hot node sampling to evaluate the predictive ability of hot nodes. Results: A total of 157 lymph nodes were detected as SLNs in 72 of 82 patients. SLN detection rate was 88%. Detection rate was 95% for the subgroups of patients with stage Ia-Ib1 disease and smaller tumor size (≤3 cm in maximal diameter). Lymph node metastasis was found in 15 patients. In 3 of them, no SLNs were detected. In the remaining 12 patients, each ipsilateral SLN contained metastasis when the pelvic lymph nodes contained metastases. Sensitivity was 100%, the false negative rate was 0%, and the negative predictive value of SLN was 100%. Conclusion: We conclude SLN detection using ^99mTc-labeled phytate is satisfactory to assess pelvic nodes in patients with early cervical cancer; if validated with other research, it should be incorporated into clinical practice.