Contrast enhanced CT and PET in lung cancer screening

This paper aims to discuss the role and the accuracy of positron emission tomography (PET) and to evaluate computed tomography (CT) contrast enhancement in diagnosing the nature of lung nodules detected by low-dose CT, performed as screening for lung cancer. When applying strict admission criteria to the test, CT contrast enhancement is feasible in 40% of nodules and gives an accurate diagnosis of benignity when enhancement is <15 HU: this occurs in only 5% of cases, but the diagnosis has to be considered certain, sparing further examination and/or follow-up. PET, performed with the most up-to-date equipment, can evaluate nodules with diameter >7 mm. The sensitivity is 87% and specificity 76%. Contrast enhancement study and PET are promising in the diagnostic work-up of lung nodules, as they reduce follow-up, the number of Fine Needle Aspiration Biopsy (FNAB), costs, radiation exposure and patients’ anxiety.