Preoperative Low Weight Affects Long-term Outcomes Following Curative Gastrectomy for Gastric Cancer

Background/Aim: A recent nationwide survey using the National Clinical Database in Japan identified a high proportion of low-weight patients, who are defined as low body mass index (BMI) patients, in comparison with Western countries. This study was designed to investigate the influence of low BMI on short- and long-term outcomes after curative gastrectomy for gastric cancer. Patients and Methods: Overall, 1,281 consecutive gastric cancer patients, who underwent curative gastrectomy with radical lymphadenectomy from 1997 through 2012 were retrospectively analyzed. Low BMI and non-low BMI were defined as a BMI<18.5 and BMI>18.5 kg/m², respectively. Results: Compared to patients with BMI higher than 18.5, those with BMI<18.5 had a significantly shorter duration of surgery (p<0.001) and tended to have lower blood loss (p=0.058). There was no difference in preoperative serum albumin level (p=0.592) and the incidence in postoperative abdominal infection complications (p=0.925) between the two groups. Whereas, BMI<18.5 was significantly associated with female gender, anemia, deeper tumor depth and nodal metastasis. Univariate and multivariate analyses revealed that the BMI<18.5 was an independent poor prognostic factor for overall survival [p=0.010, HR 1.6 (95%CI=1.32-2.30)]. Concerning recurrence, the cumulative incidence rate was significantly higher in patients with BMI<18.5 than those without (p=0.045). Conclusion: Low weight did not have adverse effects on short-term outcomes including postoperative complications. However, there was a negative prognostic impact of low BMI, suggesting the requirement of meticulous treatments and follow-up in these gastric cancer patients.