Synchronous Second Primary Neoplasms Detected by Initial Staging F-18 FDG PET/CT Examination in Patients With Non-Hodgkin Lymphoma

Purpose of the Report: Cases of synchronous non-Hodgkin lymphoma (NHL) and second primary carcinoma in previously untreated immunocompetent patients are relatively rare. The aim of this part of our prospective study was to a revealed 2-F-18 fluoro-2-deoxy-D-glucose (F-18 FDG) positron emission tomography (PET)-positive lesion in an extranodal organ suggestive of second primary neoplasm in newly diagnosed NHL patients. Materials and Methods: A total of 209 patients with NHL underwent initial staging F-18 FDG PET/computed tomography (CT). The finding was assessed by a radiologist, nuclear medicine physician, and hematologist. In 6 suspicious cases (2.9%) of second neoplasm, the decision was made to perform further investigations before lymphoma therapy. Results: Two patients were diagnosed with colorectal carcinoma, 1 with esophageal adenocarcinoma, 1 with invasive ductal breast carcinoma, 1 with medullary thyroid carcinoma, and 1 with squamous cell lung carcinoma. In 5 of the 6 patients, the second solid tumor was completely asymptomatic and revealed only by F-18 FDG PET/CT examination. Conclusions: We conclude that in patients with NHL, appropriate imaging, clinical, and histologic analysis of organ lesions detected by F-18 FDG PET/CT will occasionally demonstrate significant synchronous neoplasms.