Abstract 1682P
Background
Advanced PDAC carries a dismal prognosis with a 5-year survival rate of 3%. While treated as an even population, previous retrospective studies suggested significant different survival rates for patients (pts) with lung-only metastases (mets) when compared to other pts. This study aims to explore prospectively the difference in survival outcome based on initial site of metastases in synchronous metastatic PDAC.
Methods
This is a prospective observational study including all adult pts with synchronous metastatic PDAC in BACAP (national Anatomo-Clinical Database on Pancreatic Adenocarcinoma). Data regarding pts demographics, tumor characteristics, and survival outcomes were analyzed. Primary endpoint was overall survival (OS), defined as the time from diagnosis to death or most recent follow-up.
Results
Overall, 504 pts were included [52.4% male, mean age 69 years] of which 31 (6.2%), 58 (11.5%), 363 (72%) and 51 (10.1%) pts had lung-only, peritoneal-only, liver-only and multi-site mets at diagnosis, respectively. Most patients (79.2%) received at least one line of chemotherapy. Patients with lung-only mets were older (38.7% were > 75 years old), mostly male (61.3%) and 22.6% received at least 3 lines of chemotherapy (vs 15.5% for other patients). Median OS was significantly different according to mets site (p=0.003) (Table), with a trend towards better PFS when lung-only mets: 6.3 vs 5.4, 4.5 and 2.4 mo when peritoneal-only, liver-only and multi-site mets, respectively (p=0188).
Table: 1682P
Group | N | Event (%) | OS (mo) | 95% CI |
Lung-only | 29 | 25 (86.2) | 11.7 | [9.3; 14.6] |
Peritoneal-only | 58 | 49 (84.5) | 9.2 | [5.5; 12.9] |
Liver-only | 362 | 334 (92.3%) | 7.2 | [6.1; 8.1] |
Multi-site | 52 | 50 (96.2%) | 4.1 | [2.3; 5.0] |
Total | 501 | 458 (91.4%) | 7.2 | [6.1 ;8.1] |
p=0.003
Conclusions
Pts with lung-only mets represented 6.2% of synchronous metastatic PDAC pts and exhibited improved survival. These results suggest that a subset of pts with synchronous metastatic PDAC could benefit from more aggressive locoregional treatments. Underlying biological mechanisms contributing to survival difference are under investigation.
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
1569P - The CODRP model for predicting drug sensitivity in patient-derived 3D gastric cancer cells
Presenter: Dong Woo Lee
Session: Poster session 22
1571P - Exploration of immune and metabolism gene signature for prognosis of esophageal carcinoma and establishment of a combined prediction model
Presenter: Hao Wu
Session: Poster session 22
1572P - Impact of HER2 and PD-L1 co-expression in Claudin18.2 positive resectable gastroesophageal cancers
Presenter: Antonella Cammarota
Session: Poster session 22
1573P - Involved field and elective nodal irradiation presented similar treatment efficiency in concurrent chemoradiation for locally advanced ESCC
Presenter: Baosheng Li
Session: Poster session 22
1575P - Factors associated with uptake of adjuvant nivolumab in a nationwide esophageal cancer patient cohort
Presenter: Rob Verhoeven
Session: Poster session 22
1577P - Prior antibiotic administration disrupts outcomes of PD-1 blockade in advanced gastric cancer by altering gut microbiome and systemic immune response
Presenter: Chang Gon Kim
Session: Poster session 22
1578P - Effect of immune checkpoint inhibitors in metastatic gastric cancer: A real-world evidence study
Presenter: Francesco Puccetti
Session: Poster session 22