Surgeon volume and hospital volume in endocrine neck surgery: how many procedures are needed for reaching a safety level and acceptable costs? A systematic narrative review

The relationship between quality of care and provider's experience is well known in all fields of surgery. Even in thyroidectomies and parathyroidectomies, the emphasis on positive volume-outcome relationships is believed. It led us to an evaluation of volume activity's impact in terms of quality of care. A systematic narrative review was performed. According to the PRISMA criteria, we selected 87 paper and, after the study selection was performed, 22 studies were finally included in this review. All articles included were unanimous in attributing to activity volume of surgeons as well as centers a substantial importance. Some differences in outcomes between these investigated categories have been found: best results of the high volume surgeon is evident expecially in terms of complications, on the contrary best outcomes of a high volume center are mainly economics, such as hospital stay and general costs of the procedures. A cut-off of 35-40 thyroidectomies per year for single surgeon, and 90-100 thyroidectomies for single center appears reasonable for identifying an adequate activity. Concerning parathyroidectomy, we can consider reasonable a cut off at 10-12 operations/year. More studies are needed in a European or more circumscribed perspective.