PC	Pancreatic cancer
SARS-CoV-2	Severe acute respiratory syndrome coronavirus 2
COVID-19	Coronavirus disease 2019
IgG	Immunoglobulin G
PS	Performance status
CEA	Carcinoembryonic antigen
CA19-9	Carbohydrate Antigen 19-9
IgG4-RD	IgG4-related disease
ELISA	Enzyme-linked immunosorbent assay
NLR	Neutrophil-to-lymphocyte ratio
mGPS	modified Glasgow prognostic score
PNI	Prognostic Nutritional Index
CRP	C-Reactive Protein
AUC	Area Under the Curve.
ROC	Receiver Operating Characteristic
OS	Overall Survival