Oops, you're using an old version of your browser so some of the features on this page may not be displaying properly.

MINIMAL Requirements: Google Chrome 24+Mozilla Firefox 20+Internet Explorer 11Opera 15–18Apple Safari 7SeaMonkey 2.15-2.23

Poster Display session

334 - Prospective study of circulating tumor cells in long survivors of immunotherapy

Date

14 Dec 2018

Session

Poster Display session

Presenters

Maria Brenes Fernández

Citation

Annals of Oncology (2018) 29 (suppl_10): x1-x10. 10.1093/annonc/mdy493

Authors

M.A. Brenes Fernández1, A. Garcia Grande2, F. Franco2, M.J. Coronado1, V. Calvo2, L. Gutierrez Sanz1, J.C. Sanchez1, M. Torrente Regidor2, B. Núñez1, R. Gómez Bravo1, M. Provencio Pulla2

Author affiliations

  • 1 Oncology, Hospital Universitario Puerta de Hierro-Majadahonda, 28035 - Madrid/ES
  • 2 Oncology, Hospital Universitario Puerta de Hierro-Majadahonda, 28222 - Madrid/ES
More

Resources

Abstract 334

Background

Up to date, there isn’t current method or parameter that allows identifying long survivors in treatment with immunotherapy (IT) in a simple and accessible way. We made a prospective study of the usefulness of quantifying circulating tumor cells (CTCs) and CTCs/PDL1+ in patients treated with immunotherapy.

Methods

Patients, diagnosed with non-small cell lung cancer and in second-line treatment with IT were analyzed prospectively. CTCs from peripheral blood samples were isolated by double density gradient and immunomagnetic separation with AutoMACS equipment (M.Biotec). Quantification of CTCs was performed by Cytometry and Confocal Microscopy. The combination of both methodologies allows greater sensitivity and specificity. Samples were acquired in a MACSQuant cytometer (M.Biotec) and TCS SP5 Confocal Microscope (Leica).Data analysis was performed using MACSQuantify and LASF Lite. Determination of CTCs was made at the beginning of the treatment and every 3 months and up to 12 months during IT, together with radiological evaluation in each extraction. We selected those patients who had no progression of the disease for at least 12 months.

Results

Determination of CTCs alone did not allow us to obtain any pattern of recurrence or response. However, we were able to identify 7 patients in the group of long survivors (> 12 months of treatment with IT) using the marker PDL1. The study of their CTCs showed that none of them had circulating CTCs+/PD-L1+. Two of these patients were PDL1+ in tissue sample but negative CTC/PDL1 in blood. We also observed the presence of non-tumor WBC (white blood cells)/PDL1+, but their meaning is not clear in patients with relapse. To emphasize, another patient PDL1 + in tissue, CTC/PDL1+ in serum and low number of WBC, showed positive imaging (PET) of the progression of the disease and its CTC number increased in later determinations.

Conclusions

The absence of circulating CTCs/PDL1 + can predict a sustained response to long-term IT. Isolated CTCs without quantifying their associated expression of PDL1 are not associated with a particular pattern nor appear to be useful in identifying long survivors. WBCs that express PDL1 were associated with the appearance of relapse. Larger studies are needed to validate our results.

Editorial acknowledgement

Clinical trial identification

Legal entity responsible for the study

Hospital Universitario Puerta de Hierro Majadahonda.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.

This site uses cookies. Some of these cookies are essential, while others help us improve your experience by providing insights into how the site is being used.

For more detailed information on the cookies we use, please check our Privacy Policy.

Customise settings