Are treatment outcomes in gastric cancer associated with either hospital volume or surgeon volume?

Surgical resection is the only curative treatment for gastric cancer. Postoperative outcomes may be affected by the average or total number of surgeries carried out at an institution (hospital volume) or by a surgeon (surgeon volume). Among seven large‐scale studies that each enrolled over 10 000 patients who underwent gastrectomy, six showed that higher hospital volume contributed to a lower mortality rate after gastrectomy. Surgeon volume was also reported by three of four studies that each included over 1000 patients to be a significant factor contributing to heterogeneity in mortality rates after gastrectomy. In contrast, most studies showed no relationship between hospital volume and postoperative morbidity. A significant long‐term relationship was demonstrated in four of nine studies that each included more than 1000 patients, but the other five studies showed negative results. A recent correlative study of randomized phase III trials for gastric cancer surgeries showed a significant relationship between hospital volume and postoperative morbidity in one trial but not in another trial. There was no correlation between overall survival and either hospital or surgeon volume. In addition, another correlative study of a phase III trial of randomized chemotherapy for unresectable or recurrent gastric cancer found that there was no correlation between hospital volume and overall survival, although there was a large degree of heterogeneity in median overall survival among participating institutions.