Significance of Preoperative Pulmonary Function on Short- and Long-Term Outcomes Following Gastrectomy for Gastric Cancer.

Background: Preoperative pulmonary function assessment is useful for selecting surgical candidates and operative methods and assessing the risk of postoperative pulmonary complications. However, few studies have investigated the relationship between preoperative pulmonary function and short- and long-term outcomes in patients who underwent gastrectomy for gastric cancer.

Methods: Of the 1040 patients with gastric cancer (stages I-III) who had undergone R0 gastrectomy between 2009 and 2020, 750 who underwent preoperative spirometry were included. Restrictive ventilatory impairment was defined as a vital capacity of the predicted value (%VC) < 80%, while obstructive ventilatory impairment was defined as forced expiratory volume in one second (FEV1%) < 70%. Postoperative complications were assessed using the Clavien-Dindo (CD) classification. The relationship between clinical factors, including %VC, FEV1%, severe postoperative complications (CD ≥ 3b), overall survival (OS), and relapse-free survival, were assessed.

Results: The mean age of the 750 patients was 68 ± 10.5 years. Severe postoperative complications were observed in 25 (3.3%) patients and were significantly associated with FEV1% < 70% in the univariate analysis. The 5-year OS was 72.5%. Multivariate analysis showed that the cancer stage, age > 75 years, preoperative comorbidities, %VC < 80%, total gastrectomy, severe postoperative complications, and postoperative adjuvant chemotherapy were the significant independent factors affecting OS. Pneumonia was significantly associated with %VC < 80%.

Conclusions: FEV1% < 70%was associated with the development of severe postoperative complications, while %VC < 80% was associated with poor OS independent of the cancer stage because of death from pneumonia. Spirometry helps surgeons and patients discuss the risks and benefits of surgery.