[Typical Carcinoid of the Lung with Abnormal Elevation of Serum Pro-gastrin-releasing Peptide (ProGRP)].

A 40-year-old male was referred to our hospital because of a nodular shadow detected in the left lower lobe with the tendency to increase gently. Because fluoro-2-deoxy-D-glucose (FDG) uptake was extremely low on a FDG positron emission tomography (PET-CT), the tumor was highly suspected of the benign tumor. Five years later, a follow-up computed tomography (CT) showed the shadow to be enlarged.