Implications of BMI for the Prognosis of Gastric Cancer among the Japanese Population.

Background: The clinical significance of body mass index (BMI) on the surgical outcomes in gastric cancer patients still remains controversial.

Methods: The subjects included 427 patients who underwent gastrectomy between January 2001 and December 2005. The patients were principally divided into 3 groups on the basis of BMI: low (<18.5 kg/m2), normal (≥18.5-<25.0 kg/m2) and high (≥25.0 kg/m2).

Results: The low-BMI patients had more advanced disease than the other patients. There were no statistically significant differences in the characteristics of the normal- and high-BMI patients. The operation time was longer in the high-BMI group, but there were no differences in terms of lymph node dissection and postoperative complications among these 3 groups. The overall survival and disease-specific survival of the low-BMI group were worse than the other 2 groups. These survival rates of high-BMI group tended to be better than those of the normal BMI group; however, it was not statistically different. A multivariate analysis of these survival rate showed that a low BMI was an independent predictor of a poor prognosis.

Conclusions: A low-BMI was an independent factor of poor prognosis for overall and disease-specific survivals after surgery in Japanese patients with gastric cancer. A high-BMI was not a risk factor.