How many cases are required to learn how to perform minimally invasive pancreaticoduodenectomy?

In this manuscript by Nagakawa and colleagues (1), the authors reported on their experience with 150 consecutive cases of laparoscopic pancreaticoduodenectomy. Specifically, the outcomes of three separate surgeons performing their first 50 cases were described. Their main finding was that there was a significant learning curve for minimally invasive pancreaticoduodenectomy (MIPD).