The aim of the study is the early and non-invasive diagnosis of lung cancer in patients with pulmonary ground glass opacity. In particular, objective of the study is to evaluate the presence or absence of circulating tumor DNA (ctDNA) on the peripheral blood of patients with evidence of ground glass opacity(GGO) at CT scan and to evaluate the role that this can play in the diagnostic / therapeutic process. The ctDNA evaluation will be performed at the first radiological finding and subsequently correlated with the malignancy of the lesion based on the radiological / histological criteria regularly used in international protocols.

Secondary objective is the correlation, in patients with malignant GGO undergoing surgical treatment, of the ctDNA presence and tumor spread through the air spaces (STAS), and its correlation with local relapses.

Inclusion Criteria:

• age> 18 years
• radiological finding of pulmonary ground glass opacity
• absence of solid or haematological tumor

Exclusion Criteria:

• radio / chemotherapy treatment for at least 6 months
• patient unable to understand and express his consent to the study

Patients with radiological finding of pulmonary ground glass opacity of unknown origin