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
2667 - The impact of late-line treatment on overall survival (OS) from the initiation of first-line chemotherapy (CT) for patients (pts) with metastatic colorectal cancer (mCRC).
Presenter: Takeshi Kawakami
Session: Poster Display session 2
Resources:
Abstract
3139 - Efficacy and safety of FOLFIRI/Aflibercept (FA) in elderly population with mCRC after failure of oxaliplatin-based chemotherapy.
Presenter: Nieves Martinez Lago
Session: Poster Display session 2
Resources:
Abstract
3446 - Fluoropyrimidine-induced cardiotoxicity in colorectal cancer patients: preliminary data from the prospective observational CHECKPOINT trial (NCT02665312)
Presenter: Pasquale Lombardi
Session: Poster Display session 2
Resources:
Abstract
3969 - Comparable survival outcome between Thai patients with sporadic young adult and adult onset colorectal cancer
Presenter: Kanjana Sukhokanjanachusak
Session: Poster Display session 2
Resources:
Abstract
4455 - Impact of primary tumor side on 3-year survival outcomes of first-line (1L) FOLFOX-4 ± cetuximab in patients with RAS wild-type (wt) metastatic colorectal cancer (mCRC) in the phase 3 TAILOR trial
Presenter: Shukui Qin
Session: Poster Display session 2
Resources:
Abstract
4481 - Undetectable RAS mutant clones in plasma: possible implication for therapy and prognosis in the patient with RAS mutant metastatic colorectal cancer?
Presenter: Mohamed Bouchahda
Session: Poster Display session 2
Resources:
Abstract
5074 - Dihydropyrimidine dehydrogenase (DPD) determination prior the administration of medicines containing fluorouracil: a single Spanish hospital experience.
Presenter: Maria Dolores Mediano Rambla
Session: Poster Display session 2
Resources:
Abstract
5242 - Differences in survival between right and left-sided colorrectal cancer (CRC) in every stage, a CARESS-CCR Group Study.
Presenter: Julia Alcaide-Garcia
Session: Poster Display session 2
Resources:
Abstract
1123 - Quality of Life (QoL) in patients with aflibercept (AFL) and FOLFIRI for metastatic colorectal cancer (mCRC) – Interim analysis with focus on mutational status of the non-interventional study QoLiTrap (AIO-LQ-0113)
Presenter: Roger von Moos
Session: Poster Display session 2
Resources:
Abstract
1212 - The cost of adverse event management in patients with RAS wild-type metastatic colorectal cancer treated with first-line cetuximab and panitumumab: an Italian healthcare payer perspective
Presenter: Karl Patterson
Session: Poster Display session 2
Resources:
Abstract