“…Nearly all studies have demonstrated that a treatment related decline in CA 19-9 serum levels is associated with prolonged survival and is an independent predictor of overall survival [41,44,[53][54][55][56][57][58][59][60][61][62][63][64] (Table 5). Reni et al compared basal CA 19-9 serum levels in 247 advanced pancreatic cancer patients enrolled in five consecutive chemotherapy trials (G, gemcitabine; PEFG, cisplatin, epirubicin, 5-fluorouracil, and gemcitabine; PDXG, cisplatin, docetaxel, capecitabine, and gemcitabine) [60].…”