Table 1 Main studies assessing minimally invasive techniques for severe necrotizing pancreatitis

van Santvoort et al. [7]

Open necrosectomy vs. PD ± VARD, randomized controlled trial

88 patients (45 open necrosectomy vs. 43 PD ± VARD)

Major complications occurred in 69% of open necrosectomy patients vs. 40% of PD ± VARD patients (p = 0.006); open necrosectomy was associated with more incisional hernias (p = 0.03) and new-onset diabetes (p = 0.02). Mortality was not different.

Trial not designed to assess differences in mortality.

Bakker et al. [22]

ETN vs. VARD or open necrosectomy, randomized controlled trial

20 patients (10 ETN vs. 10 VARD/open necrosectomy)

ETN reduced both the proinflammatory response (p < 0.004) and major complications, multiple organ failure or death (p = 0.03)

Small number of patients

Bausch et al. [23]

VARD vs. ETN vs. open necrosectomy, retrospective study

32 patients (14 VARD vs. 18 ETN vs. 30 open necrosectomy)

Open necrosectomy had higher overall mortality (p < 0.05), ongoing sepsis rates and bleedings; ETN was complicated by gastric perforation in 28% of cases requiring immediate laparotomy

Small number of patients, retrospective study.

van Brunschot et al. [24]

Endoscopic transgastric drainage ± ETN vs. PD ± VARD, randomized controlled trial

98 patients

End-points are rates of major complications, need for re-interventions, quality of life, and cost-analysis between endoscopic step-up approach and surgical step-up approach. Results are still awaited.

Results still awaited

Kumar et al. [19]

ETN vs. PD ± open necrosectomy, matched cohort study

24 patients (12 ETN vs. 12 PD ± open necrosectomy)

ETN was superior in clinical remission rate (p < 0.01) and reduced major complications, length of stay, and post-operative health care utilization (p < 0.01).

Small number of patients.

Rasch et al. [25]

Open necrosectomy vs. endoscopic transgastric drainage ± ETN ± PD, retrospective multicenter study

220 patients (30 open necrosectomy vs. 190 step-up approach)

Lower complication rate (44.7 vs. 73.3%, p < 0.001), lower mortality (10.5 vs. 33.3%, p = 0.002), and lower incidence of diabetes (4.7 vs. 33.3%, p < 0.001) was demonstrated with step-up approach compared to open necrosectomy; 18.9% of step-up approach patients required open necrosectomy.

Retrospective study

Carter et al.[10]

Open necrosectomy + percutaneous necrosectomy vs. upfront percutaneous necrosectomy, case series

14 patients (4 open necrosectomy vs. 10 percutaneous necrosectomy)

Upfront percutaneous necrosectomy by sinus tract endoscopy had 20% mortality vs. 0% with open necrosectomy, but only 40% of patients required ICU (vs. 100%).

Retrospective case series, small number of patients

Gardner et al. [18]

Endoscopic transgastric drainage vs. ETN, retrospective study

45 patients (25 ETN vs. 20 endoscopic transgastric drainage)

Walled-off pancreatic necrosis successfully resolved in 88% of patients treated with ETN vs. 45% with endoscopic drainage (p < 0.01).

Retrospective study, referral center bias

Raraty et al. [12]

Open necrosectomy vs. VARD, retrospective study

189 patients (52 open necrosectomy vs. 137 VARD)

Organ failure in 31% of patients treated by VARD vs. 56% with open necrosectomy (p < 0.0001); 43 vs. 77% respectively required ICU support. Mortality rate was 19% with VARD vs. 38% with open necrosectomy (p = 0.009).

Retrospective study, referral center bias

Guo et al. [14]

Open necrosectomy vs. retroperitoneal necrosectomy, retrospective study

412 patients (108 retroperitoneal necrosectomy vs. 304 open necrosectomy)

Mortality rate was 8.3% with retroperitoneal necrosectomy vs. 20.4% with open necrosectomy (p = 0.004); complications rate and mean ICU stay were significantly lower.

Retrospective study

Tan et al. [20]

Open necrosectomy vs. ETN, multicentric retrospective study

32 patients (21 open necrosectomy vs. 11 ETN)

Acute complications rate was 86% in open necrosectomy vs. 27% with ETN (p = 0.002), ICU stay and hospitalization were significantly reduced with ETN.

Clinical severity scores were unbalanced between groups, retrospective study, small number of patients

Bang et al. [26]

Endoscopic transgastric drainage ± ETN vs. “algorithmic approach” including endoscopic drainage, ETN, PD, percutaneous necrosectomy, open necrosectomy, observational study

100 patients (47 endoscopic transgastric drainage ± ETN vs. 53 “algorithmic approach”)

Treatment success rate equal to 91% with “algorithmic approach” vs. 60% with endoscopic drainage ± ETN (p < 0.001).

Observational study without randomization, unbalanced gender and race between groups

van Santvoort et al. [11]

Open necrosectomy vs. VARD, case-matched retrospective study

30 patients (15 open necrosectomy vs. 15 VARD)

Post-operative multiple organ failure occurred in 2 patients in VARD group vs. 10 patients treated by open necrosectomy (p = 0.0008). Complications and mortality rates were equal between groups.

Retrospective study, small number of patients

Senthil Kumar et al. [15]

Open necrosectomy vs. VARD, case-matched retrospective study

30 patients (15 open necrosectomy vs. 15 VARD)

Post-operative complications in 26.6% of patients treated by VARD vs. 53.3% of patients treated by open necrosectomy (p = 0.248). Re-interventions, ICU stay, and hospitalization were similar.

Retrospective study, small number of patients

Pupelis et al. [16]

Open necrosectomy vs. ultrasound-focused necrosectomy, prospective study

58 patients (36 necrosectomy vs. 22 focused necrosectomy)

Resolution of sepsis was earlier with focused necrosectomy; ICU stay longer with open necrosectomy (p = 0.024).

Mini-invasive transgastric or percutaneous techniques not considered.

Tu et al. [13]

Open necrosectomy vs. VARD, retrospective study

50 patients (32 open necrosectomy vs. 18 VARD)

VARD was associated with shorter operative time (130 vs. 148 min, p = 0.007) and shorter hospitalization (40.8 vs. 55.9 days, p = 0.053) compared to open necrosectomy. Fewer complications with VARD (43.8 vs. 27.8%).

Retrospective study

Gluck et al. [17]

Endoscopic transgastric drainage + PD vs. PD only, retrospective study

95 patients (49 endoscopic drainage + PD vs. 46 PD only)

Endoscopic drainage + PD significantly reduced hospitalization, CT scans, and ERCPs (p < 0.05) compared to PD only.

Retrospective study

Woo et al. [21]

Endoscopic transgastric drainage or ETN vs. open necrosectomy vs. PD

30 patients (12 endoscopic treatment vs. 8 PD vs. 10 open necrosectomy)

Mean hospitalization time was 62 days with endoscopic treatment vs. 101 days with PD and 91 days with open necrosectomy (p = 0.046). Pancreatic fistula and new-onsetdiabetes were more frequent with open necrosectomy (p = 0.04, p = 0.012).

Retrospective study, small number of patients