Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Feb 12;26(4):1548.
doi: 10.3390/ijms26041548.

Circulating Epithelial Tumor Cells (CETC/CTC) in Prostate Cancer: Potential Prognostic Marker for the Risk of Recurrence During Radiotherapy

Dorothea Schott  1 , Monika Pizon  1 , Sonia Drozdz  2 , Irina Mäurer  3 , Georg Wurschi  2   4 , Katharina Pachmann  1 , Matthias Mäurer  2   5
Affiliations

Circulating Epithelial Tumor Cells (CETC/CTC) in Prostate Cancer: Potential Prognostic Marker for the Risk of Recurrence During Radiotherapy

Dorothea Schott et al. Int J Mol Sci. .

Abstract

Prostate cancer is a leading cause of cancer-related mortality in men, with radiotherapy (RT) playing a pivotal role in treatment. However, reliable biomarkers for assessing relapse risk following RT remain scarce. This study aimed to evaluate circulating epithelial tumor cells (CETC/CTC) as potential biomarkers for assessing relapse risk in prostate cancer patients undergoing RT. Peripheral blood samples were collected from 52 prostate cancer patients, and CETC/CTC were detected using the EpCAM surface marker. Patients received definitive, adjuvant, or salvage RT, and CETC/CTC counts were measured before, at mid-treatment, and at the end of RT. The association between changes in CETC/CTC counts and relapse risk was examined. CETC/CTC were detected in 96% of patients prior to RT. A significant reduction in CETC/CTC counts during RT, particularly in patients who had undergone surgery, was associated with a lower relapse risk. In contrast, an increase in CETC/CTC counts during or after RT was associated with a higher relapse risk (hazard ratio = 8.8; p = 0.002). Furthermore, 36% of patients receiving adjuvant RT and 14% of those receiving definitive RT relapsed, with a higher risk observed in patients showing increasing CETC/CTC counts during RT. Among patients receiving salvage RT, 18% relapsed, though changes in CETC/CTC counts were less significantly associated with relapse. Monitoring CETC/CTC levels during RT offers important prognostic insights into relapse risk in prostate cancer patients. While changes in CETC/CTC counts correlated with relapse, PSA levels measured during the study did not reliably reflect relapse risk in this cohort. CETC/CTC shows promise as a prognostic marker, though further studies are required to validate its clinical superiority over PSA.

Keywords: PSA; circulating epithelial tumor cells; prognostic biomarker; prostate cancer; radiotherapy; risk stratification.

PubMed Disclaimer

Conflict of interest statement

KP is the holder of the patents for the herein described method maintrac® to detect CETC/CTC. The other authors declare no conflicts of interest.

Figures

Figure 1
Figure 1
Schematic representation of the metastatic process.
Figure 2
Figure 2
Kaplan-Meier estimates of PSA-relapse-free survival in prostate cancer patients treated with definitive, adjuvant, or salvage radiation. Dots represent censored patients.
Figure 3
Figure 3
Boxplot diagram of PSA values before and after RT as a function of recurrence during the observation period.
Figure 4
Figure 4
Boxplot diagram of CETC/CTC counts as a function of (A): surgical intervention or (B): androgen deprivation therapy. * corresponds to statistical significance.
Figure 4
Figure 4
Boxplot diagram of CETC/CTC counts as a function of (A): surgical intervention or (B): androgen deprivation therapy. * corresponds to statistical significance.
Figure 5
Figure 5
(A): Boxplot diagram of the mean number of CETC/CTC in patients after surgery during RT. (B): More than a twofold increase in CETC/CTC numbers was observed in 2 patients after surgery from midterm to the end of RT. * corresponds to statistical significance.
Figure 5
Figure 5
(A): Boxplot diagram of the mean number of CETC/CTC in patients after surgery during RT. (B): More than a twofold increase in CETC/CTC numbers was observed in 2 patients after surgery from midterm to the end of RT. * corresponds to statistical significance.
Figure 6
Figure 6
(A): Boxplot diagram showing the mean number of CETC/CTC in patients undergoing definitive RT. (B): More than a twofold increase in CETC/CTC numbers in eight patients receiving definitive radiotherapy from midterm to the end of RT.
Figure 6
Figure 6
(A): Boxplot diagram showing the mean number of CETC/CTC in patients undergoing definitive RT. (B): More than a twofold increase in CETC/CTC numbers in eight patients receiving definitive radiotherapy from midterm to the end of RT.
Figure 7
Figure 7
Boxplot diagram showing the mean number of CETC/CTC in patients undergoing salvage RT. The error bar for the midterm determination exceeds the scale. In order to keep the scales comparable, the scale was not expanded.
Figure 8
Figure 8
Kaplan-Meier survival curved for prostate cancer patients who received definitive or adjuvant radiotherapy, comparing those with decreasing (upper curve) and increasing (lower curve) CETC/CTC numbers (p = 0.002). Dots represent censored patients.
Figure 9
Figure 9
Circulating epithelial tumor cells. (a) Viable CETC/CTC: In viable cells, the cell membrane is well preserved, preventing the nuclear dye PI (red) from entering the cell. (b) Dead CETC/CTC: In apoptotic cells, the cell membrane becomes permeable, allowing the nucleus to be stained with PI.
See this image and copyright information in PMC

References

    1. Leslie S.W., Soon-Sutton T.L., Skelton W.P. StatPearls. StatPearls Publishing LLC.; Treasure Island, FL, USA: 2022. Prostate Cancer. StatPearls Publishing Copyright © 2022.
    1. Hamdy F.C., Donovan J.L., Lane J.A., Mason M., Metcalfe C., Metcalfe P., Davis M., Peters T.J., Turner E.L., Martin R.M., et al. 10-Year Outcomes after Monitoring, Surgery, or Radiotherapy for Localized Prostate Cancer. N. Engl. J. Med. 2016;375:1415–1424. doi: 10.1056/NEJMoa1606220. - DOI - PubMed
    1. Zelefsky M.J., Pei X., Chou J.F., Schechter M., Kollmeier M., Cox B., Yamada Y., Fidaleo A., Sperling D., Happersett L., et al. Dose escalation for prostate cancer radiotherapy: Predictors of long-term biochemical tumor control and distant metastases-free survival outcomes. Eur. Urol. 2011;60:1133–1139. doi: 10.1016/j.eururo.2011.08.029. - DOI - PMC - PubMed
    1. Bolla M., van Poppel H., Collette L., van Cangh P., Vekemans K., Da Pozzo L., de Reijke T.M., Verbaeys A., Bosset J.-F., van Velthoven R., et al. Postoperative radiotherapy after radical prostatectomy: A randomised controlled trial (EORTC trial 22911) Lancet. 2005;366:572–578. doi: 10.1016/S0140-6736(05)67101-2. - DOI - PubMed
    1. Hoskin P.J., Rojas A.M., Bownes P.J., Lowe G.J., Ostler P.J., Bryant L. Randomised trial of external beam radiotherapy alone or combined with high-dose-rate brachytherapy boost for localised prostate cancer. Radiother. Oncol. 2012;103:217–222. doi: 10.1016/j.radonc.2012.01.007. - DOI - PubMed

Substances