CEACAM5 and neoplasm: Consistently, our study found that CA 15–3 and CEA were significant predictors of [18F]NaF PET positivity, and a separate logistic regression further identified restaging referrals and lobular histology as additional independent predictors of [18F]NaF PET positivity, underscoring the importance of integrating tumor biology and clinical context into imaging decisions to optimize patient management.