PT - JOURNAL ARTICLE AU - Ronald C. Walker AU - Gary T. Smith AU - Eric Liu AU - Brandon Moore AU - Jeff Clanton AU - Michael Stabin TI - Measured Human Dosimetry of <sup>68</sup>Ga-DOTATATE AID - 10.2967/jnumed.112.114165 DP - 2013 Jun 01 TA - Journal of Nuclear Medicine PG - 855--860 VI - 54 IP - 6 4099 - http://jnm.snmjournals.org/content/54/6/855.short 4100 - http://jnm.snmjournals.org/content/54/6/855.full SO - J Nucl Med2013 Jun 01; 54 AB - Measured human dosimetry of the 68Ga-labeled synthetic somatostatin analog 68Ga-DOTATATE has not been reported in the peer-reviewed literature. 68Ga-DOTATATE is an investigational PET/CT imaging agent that binds with high affinity to somatostatin receptor subtype 2, found on many human cancers, most classically neuroendocrine tumors but also others. Reporting of measured dosimetry of 68Ga-DOTATATE could be useful for investigations for diagnosis, staging, and restaging of somatostatin receptor–expressing tumors. Methods: We performed measured dosimetry with 68Ga-DOTATATE PET/CT scanning in 6 volunteer human subjects as part of an Institutional Review Board–approved biodistribution investigation of the use of this radiopharmaceutical for possible future use in the diagnosis of indeterminate lung nodules or lung cancer. Five subjects were imaged at 3 time points, and 1 subject was imaged at 2 time points. Dosimetry was then measured for the whole body and for specific organs. Results: There were no observed adverse events to the radiopharmaceutical in the immediate or delayed time frames, with a follow-up of 1 y. One patient had stage IV non–small cell lung cancer and remains alive but with disease progressing on treatment. For the other 5 patients, it was ultimately proven that they had benign nodules. The measured dosimetry shows that the critical organ with 68Ga-DOTATATE is the spleen, followed by the uroepithelium of the bladder, the kidneys, and the liver, in that order. Organ-specific and whole-body dosimetries for 68Ga-DOTATATE were similar to but often slightly greater than those for 68Ga-DOTATOC or 68Ga-DOTANOC but less than those for 111In-diethylenetriaminepentaacetic acid-octreotide. Conclusion: No toxicity was observed in our 6 patients, and no adverse events occurred. The measured human dosimetry of 68Ga-DOTATATE is similar to that of other 68Ga-labeled somatostatin receptor analogs.