Clear cell renal cell carcinoma (ccRCC) has a high risk of postoperative recurrence and metastasis. Accurate differentiation between ccRCC lung metastases and secondary primary lung cancer is crucial for clinical management. A 69-year-old male with a history of partial nephrectomy for ccRCC was found to have a right upper lobe pulmonary lesion during follow-up. To clarify the diagnosis, 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) and CD70-targeted 18 F-RCCB6 immuno-PET/CT were performed sequentially. 18 F-RCCB6 immuno-PET/CT showed markedly lower tumor uptake than 18 F-FDG PET/CT, strongly indicating a primary lung lesion rather than metastatic ccRCC. This case highlights the complementary role of 18 F-FDG PET/CT and 18 F-RCCB6 immuno-PET/CT in distinguishing ccRCC metastases from secondary primary lung cancer, providing critical guidance for clinical decision-making in patients with suspected pulmonary lesions and ccRCC history.
Ma et al. (Mon,) studied this question.