External Validation of Association of Baseline Circulating Tumor Cell Counts with Survival Outcomes in Men with Metastatic Castration-Sensitive Prostate Cancer

Approximately 20% of men with metastatic castration-sensitive both unadjusted and adjusted for age, Gleason score, PSA at prostate cancer (mCSPC) progress within 1 year of treatment, and androgen-deprivation therapy initiation, disease volume, de novo biomarkers to identify them up front are lacking. In a randomized status, treatment intensification, and number of altered genes. phase III trial in men with mCSPC (SWOG S1216), higher baseline Overall, 103 patients were included in the analysis. On multivariate circulating tumor cells (CTCs) were prognostic of inferior out-analysis high CTCs (≥ 5 vs. 0) were associated with poorer PFS [HR, comes. We aimed to validate these findings and interrogate corre-4.52; 95% confidence interval (CI), 1.84–11.11; P ¼ 0.001) and OS sponding tumor genomic profiles. Consecutively seen men with (HR, 3.59; 95% CI, 0.95–13.57; P ¼ 0.060). Patients with higher CTC newly diagnosed mCSPC undergoing systemic therapy and baseline counts had a greater number of altered genes and total number of CTC enumeration by CellSearch assay were included. Gene alteraalterations (all P < 0.02). In this article, for the first time, we tions were determined by comprehensive genomic profiling of externally validate the association of higher CTC counts with tumor tissue by Clinical Laboratory Improvement Amendments—inferior survival outcomes in men with mCSPC and show a certified lab. The relationship between categorized CTC counts distinct associated tumor genomic landscape. These findings and both progression-free survival (PFS) and overall survival (OS) may improve prognostication, patient counseling, and treatment was assessed in the context of Cox proportional hazards models, selection in men with mCSPC.