¹⁸F-FDG PET/CT Parameters and Standard Uptake Values Predicting Contralateral Lung Metastasis in Lung Cancer

Area of Science:

• Oncology
• Radiology
• Medical Imaging

Background:

• Contralateral lung parenchymal metastasis (CLM) is an uncommon but significant pattern in lung cancer.
• The precise mechanisms driving CLM and its predictive factors remain incompletely understood.
• ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) is a key imaging modality in lung cancer staging.

Purpose of the Study:

• To evaluate the added value of ¹⁸F-FDG PET/CT in identifying CLM in lung cancer patients.
• To investigate the causes and predictive factors associated with the development of CLM.
• To correlate imaging findings with histopathological data and survival outcomes.

Main Methods:

• Retrospective analysis of lung cancer patients categorized by the 9th tumor-node-metastasis (TNM) classification.
• Comparison of patients with and without CLM, including those with distant metastases to other organs.
• Detailed recording of ¹⁸F-FDG PET/CT findings: primary tumor characteristics, pleural status, presence of additional metastases, and standardized uptake values (SUV_max).

Main Results:

• CLM was observed in 125 cases, with 81 at diagnosis and 44 during follow-up.
• The CLM group showed significantly higher rates of satellite nodules, nodules in other ipsilateral lobes, pleural metastasis, and pleural effusion compared to controls.
• Absence of necrosis in the primary tumor and presence of ipsilateral nodules/pleural involvement were significant predictors of CLM.

Conclusions:

• ¹⁸F-FDG PET/CT plays a crucial role in identifying predictive factors for CLM in lung cancer.
• Ipsilateral nodules, pleural effusion, and pleural metastasis are significant indicators for predicting CLM.
• These imaging findings can aid in risk stratification and management of lung cancer patients.