Therapy-Associated Cancer

177Lutetium-PSMA-617 is an established treatment for patients with metastatic castration-resistant prostate cancer (mCRPC). Early response assessment is critical for optimizing patient management. Response Evaluation Criteria in Prostate Imaging (RECIP) 1.0, initially developed for Positon Emission Tomography (PET) with 68Ga-PSMA, have demonstrated prognostic value, particularly after two treatment cycles. Recent studies suggest that SPECT at cycle 2 provides prognostic information, although it reflects only the first treatment cycle, whereas PET-based RECIP, assessed after cycle 2, captures the effect of two cycles. This study aims to evaluate the prognostic value of quantitative 177Lu-PSMA-SPECT biomarkers and determine the optimal timing for RECIP-based assessment.

The purpose of this prospective, parallel-group, cohort study is to implement phenotype-guided targeted therapy based on functional signal transduction pathway (STP) activity in recurrent ovarian cancer patients using a novel mRNA-based assay. Existing targeted drugs with tolerable toxicity profiles are used to investigate the therapeutic value beyond their approved indication, which are deemed beneficial in the select group of patients with a relevant predominantly active functional STP, in order to improve survival and maintain quality of life.