Table 3.

Outcomes and prognosis in patients with gastric cancer and diabetes mellitus.

Outcomes and Prognosis	Explanations
1.Higher incidence of second primary malignancy	A 15-year follow-up study in Taiwan suggests that diabetes patients with GCa have a significantly higher incidence of second primary malignancy than non-diabetes patients with GCa.
2.Deterioration of hyperglycemia and infection at GCa diagnosis	Patients with diabetes mellitus may develop poorer glycemic control, requiring the use of insulin, and have an increased risk of tuberculosis infection when they are diagnosed with GCa.
3.Poorer prognosis	GCa patients with pre-existing diabetes or who develop postoperative hyperglycemia may have more postoperative complications and poorer survival.
4.Remission of diabetes mellitus or improved glycemic control	Patients with diabtetes and GCa who receive gastrectomy may have remission of diabetes mellitus or improved glycemic control, especially in patients receiving Billroth II reconstruction or Roux-en-Y gastric bypass. The remission of diabetes mellitus and improvement of metabolic control may be because of increased insulin secretion and improved insulin resistance resulting from reduced appetite and loss of body weight and changes in gut hormones and gut microbiota after Billroth II or Roux-en-Y gastric bypass.
5.More complications after gastrectomy or chemotherapy	Diabetes patients with GCa suffer from more complications after gastrectomy or chemotherapy. Increased complications may include gallstones, anemia, intra-abdominal infection, osteoporosis/fracture, pulmonary infection, anastomotic leakage, thrombocytopenia, acute kidney injury, etc. Diabetes patients with GCa may require prolonged stays in intensive care units, more readmission and unplanned reoperation.

GCa: gastric cancer.