Micronutrient deficiencies after gastrectomy for gastric cancer.

INTRODUCTION: Deficiencies of trace elements including zinc, copper, and selenium, after gastrectomy for gastric cancer (GC) have not been elucidated, although those of iron and vitamin B12 are well documented. This study aimed to assess micronutrient deficiencies among patients with GC before and after different types of gastrectomy. METHODS: The study enrolled 112 patients with GC who underwent curative gastrectomy, and clinical data were obtained after gastrectomy in patients without tumor recurrence. Patients were assigned into four surgical groups: distal gastrectomy with Billroth-I reconstruction, distal gastrectomy with Roux-en Y reconstruction, proximal gastrectomy with double-flap technique reconstruction and total gastrectomy (TG). Serum trace element levels were recorded in addition to iron and vitamin B12during the preoperative and postoperative follow-up periods until 24 months after surgery. In postoperative iron and vitamin B12 deficiency, these supplementations were performed at the direction of physician. RESULTS: Linear mixed-effects models demonstrated significant time effects for selenium, copper, iron, ferritin, hemoglobin and vitamin B12 (p < 0.001), whereas no significant time effect was observed for zinc. Significant time-by-surgery interactions were observed for selenium (p = 0.016), copper (p = 0.014), ferritin (p = 0.023) and hemoglobin (p = 0.001), indicating that postoperative trajectories differed according to surgical procedure for these outcomes. Zinc deficiency was observed in 51.8% of patients with GC before surgery, and a significant time-by-preoperative serum zinc status interaction was observed (p < 0.001), indicating that postoperative serum zinc levels in patients with preoperative zinc deficiency remained low. CONCLUSION: Serum iron, vitamin B12 and selenium levels decline over time following gastrectomy. Iron and selenium deficiencies were pronounced in patients who underwent TG. There was a high prevalence of preoperative zinc deficiency, and postoperative serum zinc levels in these patients remained low. Serum micronutrient levels should be monitored carefully before and after gastrectomy, and supplementation should be provided as needed, particularly in TG.