A radioconjugate composed of the orally bioavailable hydrochloride salt form of anlotinib, a receptor tyrosine kinase (RTK) inhibitor, labeled with the radioisotope carbon C 14, with potential use for evaluating the pharmacokinetic profile of anlotinib. Upon administration of carbon C 14 anlotinib hydrochloride, anlotinib targets multiple RTKs, including vascular endothelial growth factor receptor type 2 (VEGFR2) and type 3 (VEGFR3). This agent may both inhibit angiogenesis and halt cell growth in tumor cells that overexpress these RTKs. Labeling of anlotinib with the radioactive tracer carbon C 14 permits the evaluation of this agent's pharmacokinetic profile, including its absorption, distribution, metabolism, and excretion (ADME).