Background: The present study evaluated the effects of preoperative parenteral nutrition (PN) on tumor cell proliferation in malnourished gastric cancer patients.
Methods: Twenty malnourished patients affected by gastric cancer were randomized to receive the standard hospital oral diet (control group) or the standard hospital oral diet plus PN (PN group; 0.2 g/kg/d of nitrogen and 30 nonprotein kcal/kg/d). Samples of tumor tissue and surrounding health mucosa were taken by endoscopic biopsies and from the operative specimen, immediately after resection. Tissues were sent for histologic examination and prepared for flow cytometry and for the measurement of the uptake of bromodeoxyuridine (BduR) by cells after in vitro exposure to the agent. The BduR uptake is largely used to assess the proportion of cells actively synthesizing DNA and is one of the principle methods used to measure tumor proliferation.
Results: In the PN group, the mean percentage of tumor cells incorporating BduR was 2.51% +/- 1.7% in the endoscopic samples and 1.52% +/- 0.8% in the operative specimens (p = .2). In the normal mucosa, the mean percentage of cells incorporating BduR was 2.24% +/- 1.8% and 1.13% +/- 1.1%, respectively (p = .1). In the control group, the percentage of cells incorporating BduR in the normal mucosa was 1.26% +/- 1.1% at endoscopy and 0.41% +/- 0.3% at surgery (p = .2), whereas the percentage of cells incorporating BduR in the tumor tissue was 1.41% +/- 1.2% at endoscopy and 0.48% +/- 0.6% at surgery (p = .2). The percentage of S-phase cells documented by flow cytometry in the PN group was: in the tumor, 6.6% +/- 2.9% in the endoscopic samples and 5.7% +/- 2.5% in the operative specimens (p = .6); in the normal mucosa, 5.8% +/- 2.5% at endoscopy and 5.4% +/- 0.9% at surgery (p = .7). In the control group, the percentage of proliferating cells measured by flow cytometry was 4.9% +/- 3.2% in the normal mucosa taken by endoscopic biopsy and 5.3% +/- 1.4% in the normal mucosa taken from the operative specimens (p = .8), whereas it was 11.4% +/- 7.2% in the tumor taken with endoscopic biopsy and 9.7% +/- 4% in the tumor tissue taken from the surgical specimens (p = .7).
Conclusions: The present study suggests that PN does not stimulate tumor proliferation in malnourished patients affected by gastric cancer.