Table 1.

Characteristics of studies reporting on patients with pancreatic neuroendocrine tumours (PNET) submitted to open pancreatic surgery (OPS) or laparoscopic pancreatic surgery (LPS)

Authors	Year	Study type	Type of PNET	Period of patient recruitment	Country	Patients, n	LPS, n	OPS, n	Conversion, n	Study quality (Newcastle–Ottawa scale)
Espana-Gomez et al.19	2009	Retrospective	Insulinomas	1995–2007	Spain	34	21	13	7	*******
Gumbs20	2008	Retrospective	Functioning (23%) Non-functioning (77%)	1992–2006	France	31	18	13	1	*******
Hu et al.21	2011	Retrospective	Insulinomas	2000–2009	China	89	43	46	2	*******
Karaliotas & Sgourakis22	2009	Retrospective	Insulinomas	1999–2008	Greece	12	5	7	1	*******
Kazanjian et al.23	2006	Retrospective	Functioning (29%) Non-functioning (71%)	1990–2005	USA	70	4	66	NR	*******
Liu et al.24	2007	Retrospective	Insulinomas	2000–2006	China	48	7	41	3	*******
Lo et al.25	2004	Retrospective	Insulinomas	1999–2002	China	10	4	6	0	*******
Roland et al.26	2008	Retrospective	Insulinomas	1998–2007	USA	37	22	15	2	*******
Sa Cunha et al.27	2006	Retrospective	Insulinomas	1999–2005	China	21	12	9	3	******
Zerbi et al.28	2011	Prospective	Functioning (27%) Non-functioning (73%)	2004–2007	Italy	262	21	241	NR	*******
Zhao et al.29	2011	Retrospective	Insulinomas	1990–2010	China	292	46	246	19	*******
Total						906	203	703

NR, not reported.