This prospective study aims to evaluate the effectiveness of the One-Step Nucleic Acid Amplification (OSNA) technique for detecting micrometastases in lymph nodes of patients with clinical stage I-II non-small cell lung cancer (NSCLC) undergoing robotic lung resection. OSNA targets CK19 mRNA expression in order to improve the accuracy of mediastinal lymph node staging. The secondary objectives are to identify skip metastases, evaluate the potential for pathological upstaging and analyse long-term outcomes such as overall survival (OS) and disease-free survival (DFS).

This prospective study was approved by the local Ethics Committee in December 2022, and patient enrolment began in May 2023. The inclusion criteria were:

• Resectable non-small cell lung cancer (NSCLC).
• Clinical stage I-II.
• Absence of pathological lymphadenopathy in preoperative staging (cN0). The exclusion criteria included:
• Clinically advanced NSCLC
• Neoadjuvant chemo-immunotherapy
• Presence of other oncological diseases
• Patient refusal to participate. All patients underwent robotic anatomical lung resection combined with systematic lymphadenectomy. Patients were randomised into two groups based on the lymph node (LN) analysis method: OSNA technique or standard histopathological analysis (hematoxylin and eosin or immunohistochemistry).

This prospective study aims to evaluate the effectiveness of the One-Step Nucleic Acid Amplification (OSNA) technique for detecting micrometastases in lymph nodes of patients with clinical stage I-II non-small cell lung cancer (NSCLC) undergoing robotic lung resection. OSNA targets CK19 mRNA expression in order to improve the accuracy of mediastinal lymph node staging.

Cytokeratin 19 is a cytoskeletal component exclusively found in normal or neoplastic epithelial cells, and its presence in lymph nodes serves as an indicator of involvement by tumor cells of epithelial origin.The OSNA method represents a novel approach that determines the number of mRNA copies in the homogenized entire lymph node, overcoming the limitations of hematoxylin- eosin and immunohistochemistry methods that only analyze histological sections and avoiding sampling bias due to the non-uniform localization of metastatic foci. The present study aims to evaluate the advantages of using molecular lymph node assessment in homogeneous samples of patients with the same clinical stage of tumour presentation, stage I and II N0 NSCLC, to optimise data comparison and reduce the risk of potential bias.

Secondary objectives will be the identification of skip metastases and lymph node upstaging.

The future perspective of the study is to analyse long-term follow-up data through outpatient surveillance and radiological examinations to estimate possible disease recurrence and mortality rates in patients The secondary objectives are to identify skip metastases, evaluate the potential for pathological upstaging and analyse long-term outcomes such as overall survival (OS) and disease-free survival (DFS).

Inclusion Criteria:

• Resectable non-small cell lung cancer (NSCLC)
• Clinical stage I-II
• Absence of pathological lymphadenopathy in preoperative staging (cN0)

Exclusion Criteria:

• Clinically advanced NSCLC
• Prior neoadjuvant chemo-immunotherapy
• Presence of other oncological diseases
• Patient refusal to participate.

patients with clinical stage I-II non-small cell lung cancer (NSCLC) undergoing robotic lung resection.