Abstract 4557
Background
Genomic instability as characteristic for malignant transformation can be identified by quantitative sequencing. Cell-free tumor DNA (cfDNA) is a minimal invasive biomarker that can be used for tumor and therapeutic monitoring. This study evaluates quantitative cfDNA in patients (pts) with pancreatic cancer (PDAC) as an early therapeutic outcome marker.
Methods
In this prospective study plasma samples of 59 PDAC pts were collected in two centers throughout treatment with either FOLFIRINOX (n = 35) or Gemcitabine/nab-paclitaxel (n = 24). Additionally in 17 pts with FOLFIRINOX samples were collected during and 8 hours after treatment initiation. CNI scoring assays were used to quantify cfDNA. The results were correlated to CT/MRT imaging (RECIST 1.1) after 8-12 weeks, or monthly CA 19-9 and CEA values.
Results
At base-line in 55 out of 59 samples cfDNA could be detected. The CNI scores in metastasized PDAC were significant higher in comparison to locally advanced tumors (p = 0.009), however no differences occurred between the centers, therapy regime or outcome. Results to sensitivity, specificity, PPV and accuracy of CNI scores after 3 month of treatment are given in the table. Especially in sensitivity and accuracy CNI score show an advantage above classical tumor marker. Moreover, a dramatic cytolytic burst with subsequent significant increased CNI score 8 hours after treatment initiation with FOLFIRINOX was observed in 3/4 pts with PR, 1/4 pts with SD, compared to 0/9 pts with PD. This makes the CNI sore a very early predictor of treatment failure sensitive during first administration of chemotherapy.Table:
717P CNI and CA19-9 for prediction of therapy outcome
FOLFIRINOX CNI | FOLFIRINOX CA19-9 | Gem/nab CNI | Gem/nab CA19-9 | |
---|---|---|---|---|
Sens PD (%) | 73 | 36 | 50 | 18 |
Spec PD (%) | 88 | 88 | 93 | 62 |
PPV (%) | 89 | 100 | 86 | 40 |
Conclusions
Determination of cfDNA in the serum predicts treatment outcome more precise and earlier compared to classical tumor marker such as imaging or CA19-9 in PDAC patients. Prediction of non responsivness to therapy might even be possible after the first administration of FOLFIRINOX.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3034 - Efficacy and safety of neoadjuvant chemotherapy plus trastuzumab and pertuzumab in non-metastatic HER2-positive breast cancer in real life: NEOPEARL STUDY
Presenter: Maria Agnese Fabbri
Session: Poster Display session 2
Resources:
Abstract
4772 - Real world comparison of the impact of adjuvant capecitabine in women with high-risk triple-negative breast cancer after neoadjuvant chemotherapy
Presenter: Maysa Vilbert
Session: Poster Display session 2
Resources:
Abstract
5627 - Influence of age on the indication of adjuvant chemotherapy in early breast cancer using Oncotype DX. An analysis of 240 patients treated in the Institut Catala d’Oncologia (ICO) hospitals
Presenter: Sabela Recalde
Session: Poster Display session 2
Resources:
Abstract
3917 - Impact of delayed neoadjuvant systemic chemotherapy on survival among breast cancer patients
Presenter: Mariana Chavez Mac Gregor
Session: Poster Display session 2
Resources:
Abstract
2246 - Clinical Confirmation of Higher Exposure to Niraparib in Tumor vs Plasma in Patients With Breast Cancer
Presenter: Laura Spring
Session: Poster Display session 2
Resources:
Abstract
581 - The rationale for the effectiveness of systemic treatment of breast cancer depending on the body weight index
Presenter: Mohammad Hojouj
Session: Poster Display session 2
Resources:
Abstract
5327 - Response to neoadjuvant chemotherapy in HER2 non-overexpressing breast cancer subtypes
Presenter: Silvia Mihaela Ilie
Session: Poster Display session 2
Resources:
Abstract
3613 - Pre-specified interim analysis of the SAFE trial (NCT2236806): a 4-arm randomized, double-blind, controlled study evaluating the efficacy and safety of cardiotoxicity prevention in non-metastatic breast cancer patients treated with anthracyclines with or without trastuzumab.
Presenter: Lorenzo Livi
Session: Poster Display session 2
Resources:
Abstract
3736 - Safety of hypofractionated whole breast irradiation after conservative surgery for patients aged less than 60 years: a multi-center comparative study.
Presenter: Icro Meattini
Session: Poster Display session 2
Resources:
Abstract
5085 - Usefulness of NT-ProBNP as a biomarker of cardiotoxicity in breast cancer patients treated with trastuzumab
Presenter: Isabel Blancas López-Barajas
Session: Poster Display session 2
Resources:
Abstract