The impact of certification of general thoracic surgeons on lung cancer mortality: a survey by The Japanese Association for Thoracic Surgery

OBJECTIVES: The Japanese Board of General Thoracic Surgery and the annual survey by the Japanese Association for Thoracic Surgery (JATS) of certified hospitals began in 2005; since then, over 1300 specialists and 650 hospitals have been certified by this system. To evaluate how this system contributes to improving the outcomes of general thoracic surgery, the effects of the number of certified general thoracic surgeons (GTSs) and hospital volume on 30-day mortality or hospital mortality were evaluated. METHODS: Using data from the annual survey of JATS from 2005 to 2012, the outcomes of 211 619 patients who underwent lung resection for lung cancer were evaluated. The patients were divided into four groups by the level of surgery: first level, partial resection; second level, segmentectomy and lobectomy; third level, sleeve segmentectomy and lobectomy; and fourth level, pneumonectomy, sleeve pneumonectomy and pleuro-pneumonectomy. Multiple logistic regression analysis was used to examine the associations between operative mortality and the number of GTSs, hospital volume and level of surgical procedure. RESULTS: Overall 30-day and hospital mortality rates were 0.40 and 0.77%, respectively. The 30-day and hospital mortality rates for each surgical level were 0.20 and 0.35% for the first level, 0.36 and 0.73% for the second level, 1.02 and 1.81% for the third level and 2.42 and 4.26% for the fourth level, respectively. The number of GTSs was associated with lower 30-day and hospital mortality rates (P < 0.0001). On logistic analysis, number of GTSs (< 3 vs = 3), hospital volume (< 50 vs = 50) and level of procedure (1 vs 2, 3 vs 2, 4 vs 2) were significantly associated with 30-day and hospital mortality rates. For 30-day mortality, the odds ratios were 0.688 (P < 0.0001) for higher number of GTSs and 0.856 (P = 0.0510) for higher volume hospitals. In the subgroup analysis by surgical level, low 30-day and hospital mortality rates in the second and fourth surgical levels were correlated with a higher number of GTSs. CONCLUSIONS: The current decrease in overall 30-day mortality rates from the JATS data showed greater dependence on the number of GTSs than on the hospital volume. We believe that the certification system in Japan is useful for the establishment of GTS status.