{
  "id": 7840022,
  "title": "Dynamics of circulating tumor cell subsets defined by PSMA and EpCAM predict survival in metastatic castration-resistant prostate cancer patients treated with 177Lu-PSMA-617",
  "url": "https://urgent.news/2026/09/16/dynamics-of-circulating-tumor-cell-subsets-defined-by-psma-and-epcam",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-09-16T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.14.751487v1?rss=1"
  },
  "original_language": "en",
  "account": "In a study of metastatic castration-resistant prostate cancer patients treated with the radioligand 177Lu-PSMA-617, researchers examined the potential prognostic value of circulating tumor cell (CTC) subset dynamics. Utilizing a cutting-edge holographic imaging platform, they analyzed serial CTC samples before and during treatment from 39 out of 100 enrolled patients. By assessing the presence and quantities of PSMA and EpCAM proteins in CTCs through immunofluorescence staining, the team identified distinct CTC subsets.\n\nPSMA and EpCAM-protein stratification resulted in two key subsets: PSMA-/EpCAM+ and PSMA+/EpCAM+. The researchers found that patients who responded to treatment (PSA50 responders) experienced a more significant increase in the PSMA-/EpCAM+ subset (6.2% to 18.7%) compared to non-responders (7.9% to 15.4%). This shift corresponded to a decrease in the PSMA+/EpCAM- subset, while the PSMA+/EpCAM+ subset remained unchanged. On-treatment counts of 5 or fewer CTCs were linked to shorter overall survival in both PSMA+/EpCAM+ and PSMA+/EpCAM- subsets (HR 3.56, 95%CI 1.32-9.60 and HR 7.50, 95%CI 0.96-52.99, respectively).\n\nFurthermore, the study revealed that on-treatment declines in the PSMA+/EpCAM+ and PSMA+/EpCAM- subsets were not associated with improved overall survival. The research concludes that dynamic changes in CTC subsets distinguished by PSMA and EpCAM expression could provide valuable prognostic information for patients receiving 177Lu-PSMA-617 therapy.",
  "summary": "Background: 177Lu-PSMA-617 radioligand treatment represents a major advancement in the management of metastatic castration-resistant prostate cancer (mCRPC), but key questions remain about tumor-cell dynamics and evolution in patients who have received this drug. Here, we used a circulating tumor cell (CTC) capture assay to assess the prognostic capacity of CTC subset dynamics following…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}