Application value of indocyanine green fluorescence in sentinel lymph node biopsy for early-stage tongue cancer and oropharyngeal cancer.

OBJECTIVES: Occult cervical lymph node metastasis is the most important reason for recurrence of early-stage tongue cancer and oropharyngeal cancer. Cervical sentinel lymph node (SLN) biopsy may help to identify them. Pigment dyes and radionuclide were used to label SLN. Both of them had shortage. This study aims to investigate the application and clinical value of indocyanine green fluorescence imaging in cervical SLN biopsy for patients with early-stage tongue cancer and oropharyngeal cancer. METHODS: Retrospective analysis was conducted on 23 patients with early tongue cancer and oropharyngeal cancer, who received surgical treatment and used indocyanine green as a tracer to find SLN in Hunan Cancer Hospital from April to October 2021. The detection rate of SLN was calculated and the distribution of SLN in different regions of the neck was analyzed. RESULTS: SLN was successfully identified in 22 of 23 patients, with a detection rate of 95.65%. Among these 22 patients, 3 patients were found to have cancer metastasis, and the rate of occult lymph node metastasis was 13.63%. No pathologically positive lymph nodes were detected in SLN-negative patients, and thus the positive predictive rate was 100%. For patients with primary lesions located in the anterior 2/3 of the tongue, the constituent ratios of SLN in neck area I, II, III, and IV were 15.15%, 71.72%, 13.13%, and 0, respectively. For patients with primary lesions located in base of the tongue, the constituent ratios of SLN in neck area I, II, III, and IV were 0, 44.44%, 44.44%, and 11.12%, respectively. CONCLUSIONS: Indocyanine green fluorescence imaging has a high detection rate with accurate positive prediction in the anterior cervical SLN biopsy in patients with early-stage tongue cancer and oropharyngeal cancer. Meanwhile, it can also reflect the lymphatic drainage of tumors located at different primary sites, which has high clinical value.