TABLE I.

Study characteristics: design, quality, population, interventions, and outcomes of interest

Reference	Study design	Duration and country	Patients		Quality scorea	Co-interventions (%)	Outcomes
			(n)	Condition
Scoggins et al.,19999	Single-institution retrospective observational	1985–1997 United States	89 I: 66 C: 23	Symptomatic and asymptomatic	Low: 4/9	No information provided about other interventions	Median os (months): I: 14.5 vs. C: 16.6, p=ns pocri 30%, ptcrc 9%
Ruo et al., 20036	Single-institution retrospective observational	1996–1999 United States	230 I: 127 C: 103	Asymptomatic or minimally symptomatic	Low: 4/9	Chemotherapyb: I: np; C: 83	Median os (months): I: 16 vs. C: 9, p≤0.05 pomri 2%, pocri 21%, ptcrc 29%
Tebbutt et al., 200310	Single-institution retrospective observational	1990–2000 United Kingdom	362 I: 280 C: 82	Symptomatic and asymptomatic	Low: 5/9	Chemotherapy: I: 100; C: 100 Novel therapy: 0 Radiation therapy: I: 10; C: 18 Metastasectomy: I: 2; C: 1	Median os (months): I: 14 vs. C: 8.2, p=ns ptcrc 19%, nrpc 6.7%, nrpi 9.7%
Michel et al., 200425	Retrospective single-institution observational	1996–1999 France	54 I: 31 C: 23	Asymptomatic or minimally symptomatic	Low: 4/9	Chemotherapy: I: 97; C: 100 Novel therapy: I: 80; C: 83; Metastasectomy: I: np; C: 9	Median os (months): I: 21 vs. C: 14, p=ns pomri 0%, ptcrc 35%
Temple et al., 200413	Population-based using seer and Medicare data	1991–1999 United States	9011 I: 6469 C: 2542	≥65 Years, symptomatic and asymptomatic	Fair: 6/9	Chemotherapy: I: 47; C: 31 Radiation: I: 12; C: 15 Metastasectomy: I: 5.2; C: 1.3	Median os (months): I: 10 vs. C: 3, p<0.05 pomri 9%, ptcrc 63%, nrpc 32%
Benoist et al., 200512	Retrospective single-institution case–control	1997–2002 France	59 I: 32 C: 27	Asymptomatic or minimally symptomatic	Fair: 6/9	Chemotherapy and novel therapy: I: 94; C: 100 Metastasectomy: I: 16; C: 22	Median os (months): I: 22 vs. C: 23, p=ns pomri 0%, pocri 22%, ptcrc 15%, nrpc 15%
Konyalian et al., 200724	Retrospective single-institution cohort	1991–2002 United States	109 I: 62 C: 47	Symptomatic and asymptomatic	Low: 5/9	Chemotherapyb: I: 71; C: 60 Radiation therapy: I: 27; C: 34	Median os (months): I: 12.5 vs. C: 4.6, p<0.05 pomri 5%, pocri 20%, ptcrc 57%
Galizia et al., 200811	Retrospective single-institution observational	1995–2005 Italy	65 I: 42 C: 23	Asymptomatic or minimally symptomatic	Fair: 6/9	Chemotherapy: I: 100; C: 100b Metastasectomy: I: 12; C: 4	Median os (months): I: 15.2 vs. C: 12.3, p=0.003 pomri 0%, pocri 21%, ptcrc 31%, nrpc 22%
Evans et al., 200923	Retrospective single-institution observational	1999–2006 United Kingdom	97 I: 45 C: 52	Symptomatic and asymptomatic	Low: 4/9	Chemotherapy: I: np; C: 42b Radiation therapy: I: np; C: 8	Median os (months): I: 11 vs. C: 7, p=ns pomri 16%, ptcrc 23%, nrpc 50%
Aslam et al., 201021	Retrospective multicentre observational	1998–2007 United Kingdom	647 I: 366 C: 281	Minimally symptomatic	Low: 5/9	Chemotherapy: I: 63; C: 36b	Median os (months): I: 14.5 vs. C: 5.8, p<0.05 pomri 7%, pocri 32%, nrpc 46%
Chan et al., 201022	Retrospective population-based	2000–2002 Canada	411 I: 286 C: 125	Symptomatic and asymptomatic	Low: 5/9	Chemotherapy: I: 61; C: 58 Novel therapy: I: 57; C: 36 Metastasectomy: I: 10; C: 0	Median os (months): I: 14 vs. C: 6, p<0.05 nrpc 22%, nrpi 4%
Seo et al., 201026	Single-institution retrospective observational	2001–2008 South Korea	227 I: 144 C: 83	Asymptomatic or minimally symptomatic	Fair: 6/9	Chemotherapy: I: 100; C: 100 Novel therapy: I: 85; C: 82 Radiation therapy: I: 10; C: 12	Median os (months): I: 22 vs. C: 14, p=ns pomri 0%, pocri 35%, ptcrc 19%, nrpc 7%, nrpi 2%
Karoui et al., 20118	Retrospective multicentre observational	1998–2007 France	208 I: 123 C: 85	Symptomatic and asymptomatic	Low: 5/9	Chemotherapy: I: 100; C: 99 Novel therapy: I: 89; C: 93 Metastasectomy I: 23; C: 29	Median os (months): I: 30.7 vs. C: 21.9, p=0.004 ptcrc 27%, nrpc 27%
Venderbosch et al., 20117 and Koopman et al., 200749 (cairo)	Retrospective multicentre cohort of a rcta	2003–2004 (recruitment period) Netherlands	399 I: 258 C: 141	Symptomatic and asymptomatic	Fair: 6/9	Novel therapy: 100 in both groups	Median os (months): I: 16.7 vs. C: 11.4
Venderbosch et al., 20117 and Tol et al., 200950 (cairo 2)	Retrospective multicentre cohort of a rcta	2005–2006 (recruitment period) Netherlands	448 I: 289 C: 159	Symptomatic and asymptomatic	Fair: 6/9	Novel therapy: 100 in both groups	Median os (months): I: 20.7 vs. C: 13.4

^aAssessed using the Ottawa–Newcastle scale for nonrandomized studies (see Appendix b for score details).

^bInformation about novel therapy (second- and third-generation anticancer therapy) was not provided. Six studies did not report postoperative mortality; eight studies did not provide postoperative morbidity; four studies did not provide information on primary tumour complication rates; six studies did not provide information on non-resection procedures in the control group, and twelve studies did not provide information on the intervention group; no study provided information about quality of life.

I = intervention group; C = control group; os = overall survival; ns = nonsignificant; pocri = postoperative nonfatal complication rate, intervention group; ptcrc = primary tumour complication rate, control group; np = not provided; pomri = postoperative mortality rate, intervention group; nrpc = non-resection procedures, control group; nrpi = non-resection procedures, intervention group; seer = Surveillance, Epidemiology and End Results; rct = randomized controlled trial.