Serial Imaging of the Novel Radiotracer [^18F] FLuorthanatrace ([^18F] FTT) by PET/CTF

Inclusion Criteria: * History of known or suspected solid tumor. * At least one lesion ≥ 1.0 cm that is seen on standard imaging (e.g. computed tomography \[CT\], magnetic resonance imaging \[MRI\], ultrasound, fludeoxyglucose \[FDG\] PET/CT). Exclusion Criteria: * Females who are pregnant or breast feeding at the time of screening will not be eligible for this study; a urine pregnancy test will be performed in women of child-bearing potential \< 2 weeks prior to screening as standard of care. * Inability to tolerate imaging procedures in the opinion of an investigator or treating physician. * Any current medical condition, illness, or disorder as assessed by medical record review and/or self-reported that is considered by a physician investigator to be a condition that could compromise participant safety or successful participation in the study.