Lack of preoperative enteral nutrition reduces gut-associated lymphoid cell numbers in colon cancer patients: a possible mechanism underlying increased postoperative infectious complications during parenteral nutrition.

OBJECTIVE: To examine preoperative dietary influences on gut-associated lymphoid tissue (GALT) cell number in the context of postoperative infectious complications.
BACKGROUND: There is little clinical evidence regarding whether nutritional routes affect GALT size and/or phenotype. The influence of GALT atrophy on clinical outcomes is also unclear.
METHOD: Patients with complete obstruction of the colon due to a tumor were excluded from this study. Study 1. Resected terminal ileum specimens, from 62 patients [preoperative parenteral nutrition (PN): n = 15, preoperative oral feeding (OF): n = 47] who underwent right colectomy during the period from 1997 to 2004 at our department, were immunohistochemically stained for counting numbers of T, IgA-producing, and mature and immature dendritic cells (DCs) in the lamina propria (LP) and intraepithelial space.Study 2. We reviewed 341 patients (PN: n = 99, OF: n = 242) with colon cancer who underwent colectomy during this period for postoperative complications.
RESULTS: Study 1. T cell numbers in the LP and intraepithelial space and IgA-producing cell number in the LP were significantly lower in the PN than in the OF group. Mature DC number in the LP was significantly lower in the PN than in the OF group, whereas total DC numbers (both mature and immature DC) were similar in the 2 groups.Study 2. The PN group had significantly higher rates of total infectious complications, surgical site infection, pneumonia, infectious colitis, and central venous catheter infection.
CONCLUSIONS: Lack of enteral delivery of nutrients reduces numbers of T and IgA-producing cells, as well as mature DCs, in GALT of colon cancer patients, as it does in animal models. A close association between GALT changes and infectious complication morbidity was confirmed.