This is a prospective, multicenter observational study aim at estimating the potential clinical utility of the CBM and at establishing the SOPs and protocols for a future randomized control trial.

Objectives:

• To obtain the combined biomarker model (hs-CYFRA 21-1, radiomics, Mayo) score in a prospective observational trial and estimate potential clinical utility compared to the Mayo Model.
• To establish standard operating procedures (SOPs) and protocols in a prospective observational trial in anticipation of a future randomized control trial. These include the REDCAP data input protocols, the radiomic protocols, blood draws in the CLIA environment, and estimating the CBM score in a time reasonable for clinical practice (< 2 weeks).

Inclusion Criteria:

• Adults > 21 y/o
• IPNs 8-30mm referred for evaluation Figure 4. AUC and reclassification of Combined Biomarker Model
• Intermediate risk IPN defined as 10-70% risk after applying Mayo risk predictor model
• Solid nodules or part-solid nodules with solid component >=8mm
• CT scan with nodule of concern performed within 60 days of enrollment

Exclusion Criteria:

Pure ground glass nodule or subsolid nodule with solid component <8mm

• Currently on therapy for any cancer
• History of primary lung cancer within the last 5 years
• Multiple nodules highly suspicious for metastatic disease
• Other malignancy within the last 2 year - Excluding skin cancer other than melanoma
• Pregnant women
• Prisoners
• Inability to provide informed consent
• Serologic evidence of active fungal infection

Patients recruited from pulmonary or thoracic clinics that have indeterminate pulmonary nodules