The impact and value of preoperative lymph node dissection on survival in primary lung carcinoma

Aim: Surgical mediastinal staging techniques are used during lung cancer staging workup along with imaging and endoscopic techniques. Videomediastinoscopy is recommended for sampling at least subcarinal and lower paratracheal stations. Despite development of new techniques like video-assisted mediastinoscopic lymphadenectomy (VAMLA) for more accurate detection of lymph node involvement, the role of lymphadenectomy remains debated. We aimed to investigate the relationship between the number of lymph nodes assessed during preoperative staging and survival in patients with lung cancer. Material and Method: Lung cancer patients who had undergone preoperative surgical mediastinal staging in our department between January 2010-December 2023 were included. A lymph node involvement map is established according to the location of primary tumor. Univariable and multivariable survival analyses were conducted to evaluate the impact of staging modality, clinical features, pathological features, and the number of excised lymph nodes on survival. Results: Excising ≥24 piece of lymph nodes during preoperative staging and ≥45 pieces during surgical resection in addition to preoperative staging is found to be associated with worse survival (p=0.028 [odds ratio(OR)] 1.39, [%95 confidence interval (CI)] 1.03-1.87 and p=0.045[OR 1.40, %95 CI 1.00-1.96]), respectively). Gender (p=0.048 [OR 1.42, %95 CI 1.00-2.02]), cT staging (p=0.013 [OR 1.14, %95 CI 1.02-1.27]) and having resectional surgery (p=0.024 [OR 0.71, %95 CI 0.53-0.95]) were also independently associated with survival. Conclusion: It is recommended to excise maximum 24 pieces of lymph node during preoperative mediastinal staging and 45 pieces during surgical resection in addition to staging, while also considering the location of primary tumor.