Incidental finding of prostate cancer and adenomatous colon polyp in a patient with lung cancer

A 60-year old man presented to our institution for the management of a newly diagnosed, well-differentiated adenocarcinoma of the right lung, which had been discovered during the work-up for a transient ischemic attack at another institution. The first diagnostic imaging test the patient underwent was a F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) scan ordered by a surgeon at our institution. The PET/CT image revealed that the adenocarcinoma was a localized tumor, with no evidence of metastasis. However, it also showed intense FDG uptake in the prostate gland and transverse colon, which a biopsy proved to be a prostatic adenocarcinoma and a villotubular adenoma with high-grade dysplasia in a colonic polyp, respectively. Neither had been suspected before the scan was ordered.As illustrated in this case, PET/CT can lead to early detection of unknown malignant lesions that may potentially improve a patient's outcome. It provides unique insights into the molecular pathways of diseases and the biological behavior of tumors that, combined with anatomic information, have an important role in today's oncology.