Feasibility of RPD has been demonstrated by several independent groups [
9,
11‐
13]. A collaborative study reporting on the outcome of the first RPDs performed at 5 centers between January 2008 and August 2014 demonstrated that RPD can be safely implemented in selected patients at high-volume centers. In detail, in a total of 92 patients with a mean age of 65 ± 12 years, a mean body mass index of 25.8 ± 5.0 kg/m
2, a prevalence of male gender (53%), and a proportion of ASA III patients of 46%, median operating time was 504 min (interquartile range 133), median estimated blood loss was 242 ml (interquartile range 398), and conversion to open surgery was required in 12 procedures (13%). Regarding pancreatic anastomosis, pancreaticojejunostomy was employed in all but 2 patients and temporary ducts stents were inserted in the majority of patients (69.5% overall, and 86.7% in patients with pancreatic duct diameter < 3 mm) irrespective of type of anastomosis (i.e., invaginating or duct-to-mucosa). Clinically relevant post-operative pancreatic fistula (CR-POPF) developed in 9 patients (9.9%; 4 grade B and 5 grade C). Rate of severe post-operative complications was 24% with 2 (2.2%) deaths and ten (10.9%) reoperations. A margin negative resection was achieved in 75% of the patients with pancreatic cancer with mean harvest of 16 ± 8 lymph nodes [
14]. In subsequent studies, RPD was associated with extremely low rates of conversion to open surgery (ranging from 1.1% to 5.1%) [
15,
16]. When compared with OPD, RPD required longer operating times [
17], but reduced blood loss and need for blood transfusions [
18]. In an early study, Chalikonda and coworkers reported a post-operative death caused by a portal vein injury requiring emergent conversion to open [
12]. This dreadful occurrence is not specific to RPD and has already been reported also for laparoscopic PD (LPD) [
19]. In a recent collaborative study, conversion to open was required in 65 of 709 minimally invasive PDs (9.1%), including 48 elective conversions (6.7%) and 12 emergency conversions (1.6%). Reasons for conversion were unknown in 5 patients. The incidence of conversion in LPD was twice as high when compared to RPD [52 of 459 (11.3%) versus 13 of 250 (5.2%);
p = 0.007]. At multivariable analysis, using RPD as reference, LPD was strongly associated with conversion to open surgery (OR 5.2; 2.5–10.7;
p < 0.001). Conversions were more frequent in medium-volume centers (10–19 procedures per year) than in high-volume centers (15.2% versus 4.1%;
p = 0.001) [
20].
Several studies have described the learning curve for RPD, mostly using cumulative summative (CUSUM) analysis of operating time. Excluding one article defining the simultaneous learning curve of two surgeons at 80 procedures [
21], the number of cases required to overcome the learning curve for a single surgeon ranged between 20 and 40 RPDs [
22‐
26]. Implementation of mentorship and a proficiency-based curriculum could not affect POPF rate, but was shown to reduce operating times, conversion rates, severe post-operative complications, and estimated blood loss [
27]. A recent systematic review on the learning curve of LPD and RPD showed that the learning curve of a single surgeon was considerably longer for LPD [49.8 (95% CI 43.8–56.4) versus 28.3 (23.3–34.0); IRR: 1.76, 95% CI 1.04–2.99;
p = 0.0360], while the Institutional learning curve was longer for RPD [43.6 (95% CI 38.0–49.8) versus 21.0 (95% CI 17.5–25.0)] although the difference was not statistically significant [
28].
One study showed that based on operating times, 35 cases are required to overcome the learning curve of RPD with vein resection. Completion of the learning curve, however, was associated only with reduction in length of hospital stay, without improvement in estimated blood loss, margin status, post-operative pancreatic fistula, severe complications, and post-operative mortality [
30].