Clinical efficacy of protein-bound polysaccharide K in patients with gastric cancer undergoing chemotherapy with an oral fluoropyrimidine (S-1).
BACKGROUND
The aim of the present study was to evaluate the clinical significance of protein-bound polysaccharide K (PSK) in patients with primary gastric cancer who were being treated with an oral fluoropyrimidine (S-1).


METHODS
Clinical reports of 190 gastric cancer patients treated with S-1 chemotherapy, with or without PSK, at Kochi Medical School between 2007 and 2012 were investigated retrospectively to analyze survival. The neutrophil:lymphocyte ratio (NLR) was also evaluated as indicator of the immunoenhancing effect of PSK.


RESULTS
Overall survival was significantly longer in patients treated with S-1 + PSK than in those given S-1 alone (hazard ratio for death, 0.608; 95% confidence interval 0.375-0.985; P = 0.041). Furthermore, there was a tendency for changes in the NLR during chemotherapy to be lower in the S-1 + PSK group than in the S-1 group, but the difference did not reach statistical significance (P = 0.054). When patients were divided into groups based on preoperative NLR (i.e. <2.5 and ≥2.5), the mean (±SEM) NLR 1 month after the beginning of chemotherapy in the NLR ≥2.5 subgroup was significantly lower in patients treated with S-1 + PSK rather than S-1 alone (1.7 ± 0.7 vs. 3.3 ± 4.1, respectively; P = 0.043).


CONCLUSIONS
Immunochemotherapy using PSK improves the survival of patients with advanced gastric cancer. The NLR may be a useful biomarker for evaluating prognosis in these patients.
['Namikawa|T|T|', 'Fukudome|I|I|', 'Ogawa|M|M|', 'Munekage|E|E|', 'Munekage|M|M|', 'Shiga|M|M|', 'Maeda|H|H|', 'Kitagawa|H|H|', 'Kobayashi|M|M|', 'Hanazaki|K|K|']
D000230:Adenocarcinoma D000368:Aged D000369:Aged, 80 and over D000971:Antineoplastic Combined Chemotherapy Protocols D004338:Drug Combinations D005260:Female D005656:Fungal Proteins D006801:Humans D007167:Immunotherapy D053208:Kaplan-Meier Estimate D018655:Lymphocyte Count D008214:Lymphocytes D008297:Male D008875:Middle Aged D009504:Neutrophils D010094:Oxonic Acid D011134:Polysaccharides D012189:Retrospective Studies D013274:Stomach Neoplasms D015996:Survival Rate D005641:Tegafur
Gastric cancer Immunochemotherapy Neutrophil to lymphocyte ratio Oral fluorouracil anticancer drug Protein-bound polysaccharide-K