This estimates the likelihood that an incidentally found lung nodule on CT is cancerous, based on patient and nodule characteristics — helping guide whether further imaging, biopsy, or monitoring is appropriate.
Low probability — often CT surveillance.
Intermediate — consider PET or biopsy.
High probability — favor definitive workup.
No — it estimates probability to help guide the intensity of follow-up (watchful waiting with repeat imaging vs. biopsy), not a definitive diagnosis either way.
By convention, under 5% is low probability, 5–65% is intermediate, and above 65% is high probability of malignancy.
Larger diameter, spiculated (spiky) margins, older age, a history of extrathoracic cancer, current or prior smoking, and upper-lobe location.
The Mayo Clinic (Swensen) model for solid pulmonary nodules. Other validated models (like the Brock model, used for screening-detected nodules) exist and may fit different settings.