Introduction: Lung cancer is the most common cause of cancer death in the Czech Republic, in part due to its significant metastatic potential. The aim of this study was to collect real data on the metastatic potential and clinical characteristics of T1a and T1b lung cancer in the Czech population and to investigate potential factors that would predict an increased risk of lymph node metastasis.
Methods: Prospective-retrospective study conducted at the Department of Surgery of the University Hospital Ostrava during the period from January 1, 2015, to July 31, 2022. The study included patients who underwent lobectomy or bilobectomy for T1a and T1b non-small cell lung carcinoma.
Results: Out of a total of 165 patients with T1a and T1b lung carcinoma, 17.6% of patients were confirmed to have metastatic involvement of the lymph nodes (with 9.1% classified as N2 lymph node involvement). The highest percentage of positive lymph nodes was observed in patients with tumors located in the upper left lobe (29.5%) and lower right lobe (23.3%). Adenocarcinoma was the most commonly metastasizing carcinoma, with 21.1% of patients showing positive lymph nodes. Neuroendocrine carcinoma metastasized in 19.4% of cases, while squamous cell carcinoma did so in 6.8% of cases. The cumulative risk of having positive lymph nodes in T1a and T1b adenocarcinoma located in the upper left lobe reached 40.0%, of which the risk of N2 lymph node involvement was 25.0%.
Conclusion: T1a/b non-small cell lung cancer exhibits significantly lower metastatic potential than T1c tumors and higher. Adenocarcinoma showed a 3-fold higher metastatic potential than squamous cell carcinoma, indicating the need for increased attention in the treatment of lung adenocarcinoma, especially in tumors localized in the upper left lobe, where a cumulative risk of lymph node metastasis of up to 40% was observed.
Keywords: T1a; T1b; lung cancer; lymph node involvement; metastatic potential.