DETERMINATION OF THE PREVALENCE OF OCCULT NECK LYMPH NODE INVOLVEMENT IN PATIENTS WITH LARYNGEAL SQUAMOUS CELL CARCINOMA

Background & Aims: Squamous cell carcinoma (SCC) accounts for 85% of laryngeal cancers. In some cases, lymph nodes do not show any specific symptoms despite being involved by cancer. Previous studies showed that patients undergoing selective neck lymph node dissection (SND) had significantly lower recurrence rates. We investigated the prevalence of occult neck lymph node involvement in patients with laryngeal SCC, and this is an important step in performing targeted selective neck lymph node dissection (SND) in these patients. Materials & Methods: This is a descriptive, retrospective, cross-sectional study involving the clinical records of patients with laryngeal carcinoma referred to Amir Alam Hospital from 2012 to 2017. Clinical and radiologic data showed that 66 patients had laryngeal SCC and were in the N0 stage. This group of patients was considered as the statistical sample of the study. A number of patients with similar status were excluded because of incomplete case data. Data analysis was done with SPSS v.22 software. Results: Of the total number of patients 29(44%), were diagnosed with glottic cancer, 29 (44%) with supraglottic cancer and 8 (12%) with subglottic cancer. 26 (39.5%) of these patients had lymph node metastasis (occult metastasis approved by post-operative pathology report). No metastasis in lymph nodes was found in 40(60.5%) patients. Of the 66 targeted patients, only 13 underwent radiotherapy before surgery. Of the 26 patients who had lymph node metastasis, 11 were diagnosed with glottic cancer and 13 patients with supraglottic cancer and 2 cases with subglottic cancer. Conclusion: Considering the nearly 20% prevalence of occult lymph node metastasis in patients with laryngeal squamous cell carcinoma who are in the N0 stage, it is recommended to selectively excise the neck lymph nodes in addition to the tumor surgery as this will reduce the recurrence rate of the disease.