Use of SPECT-CT for Comparison of Dosimetry Methods in PSMA-targeted Radioligand Therapy (SPECTacular Study)

The SPECTacular study will enroll patients who are already undergoing a FDA approved PSMA-targeted Radioligand treatment cycle. During each treatment cycle, patients will receive 5 additional SPECT/CT scans to investigate the limits of agreement between dosimetry (absorbed radiation dose) approximation methods and dosimetry using the triexponential fitting method.

All patients with PSMA-positive tumor and/or Metastases of Prostate Cancer (PSMA-TMPC) who would be undergoing a PSMA-targeted Radioligand Therapy (PRLT) based on independent eligibility criteria for the same, will receive 6 serial SPECT-CT scans for every treatment cycle as a part of our study. The purpose of this investigation is to assess the limits of agreement of commonly employed dosimetry methods used to determine or approximate absorbed doses for organs and tumors compared to a dosimetry method using a triexponential fit requiring 6 post-injection SPECT-CT scans for all treatment cycles.