Role of minimally invasive techniques in gastrointestinal surgery: Current status and future perspectives

Table 1 Studies on laparoscopic surgery in gastric cancer

Ref.	Study type	Comparison	Group	Endpoints	Results
Kim et al[31], KLASS-01-RCT, 2019	Randomized clinical trial	Laparoscopic distal gastrectomy vs open distal gastrectomy on long-term survival among patients with stage I gastric cancer	LADG (n = 706); ODG (n = 711)	5-yr overall survival rate and 5-yr cancer-specific survival rate	No significant difference between the two groups in the 5-yr overall survival rate (94.2% vs 93.3%) or 5-yr cancer-specific survival rate (97.1% vs 97.2%)
Lee et al[30], KLASS-02-RCT, 2019	Multicenter randomized controlled trial	Laparoscopic distal gastrectomy (LDG) vs open distal gastrectomy (ODG) for D2 lymphadenectomy	LADG (n = 526); ODG (n = 524)	Thirty-day morbidity, 90-d mortality, postoperative pain, and recovery	Laparoscopic distal gastrectomy was associated with a lower complication rate, faster recovery, and less pain (P < 0.05), and there was no significant difference in mean number of totally retrieved lymph nodes (46.6 vs 47.4, P = 0.451)
Hyung et al[24], KLASS-02-RCT, 2020	Randomized clinical trial	Laparoscopic distal gastrectomy surgery vs open distal gastrectomy surgery for locally advanced gastric cancer	LADG (n = 492); ODG (n = 482)	3-yr relapse-free survival rate	No significant difference between the two groups in the 3-yr relapse-free survival rate (80.3% vs 81.3%)
Yu et al[25], The CLASS-01 RCT, 2019	Randomized clinical trial	Laparoscopic distal gastrectomy surgery vs open distal gastrectomy for early-stage gastric cancer	LADG (n = 519); ODG (n = 520)	3-year disease-free survival rate	No significant difference between the two groups in 3-year disease-free survival rate (83.1% vs 85.2%)
Liu et al[27], The CLASS-02, 2020	Multicenter randomized clinical trial	Laparoscopic total gastrectomy (LTG) vs open total gastrectomy (OTG) for patients with clinical stage I gastric cancer	LTG (n = 105); OTG (n = 109)	Morbidity and mortality within 30 d following surgeries; recovery courses; postoperative hospital stays	No significant difference in morbidity and mortality within 30 d following surgeries
Katai et al[26], JCOG0912, 2020	A multicenter, non-inferiority, phase 3 randomized controlled trial	Laparoscopy-assisted distal gastrectomy (LADG) vs open distal gastrectomy (ODG) for patients with clinical stage I gastric cancer	LADG (n = 462); ODG (n = 459)	Relapse-free survival	LADG was non-inferior to ODG for relapse-free survival (94% vs 95.1%, P < 0.05), and LADG should be considered a standard treatment option
Kinoshitaet al[28], LOC-A Study, 2019	Multicenter cohort study	Laparoscopic gastrectomy (LC) vs open gastrectomy (OP) for locally advanced gastric cancer	LC (n = 305); Op (n = 305)	5-yr overall survival; recurrence rate; hazard ratio for recurrence (HR)	No significant difference between the two groups in the 5-yr overall survival (53.0% vs 54.2%) and recurrence rate (30.8% vs 29.8%)
Park et al[29], COACT 1001, 2018	Randomized phase II multicenter clinical trial	Laparoscopy-assisted distal gastrectomy (LADG) with D2 lymph node dissection vs open distal gastrectomy (ODG) for the treatment of advanced gastric cancer	LADG (n = 105); ODG (n = 99)	Noncompliance rate of the lymph node dissection; 3-yr disease-free survival (DFS), 5-yr overall survival, complications, and surgical stress response	No significant difference between the two groups in the noncompliance rate of lymph node dissection (47.0% vs 43.2%) and 3-yr DFS (80.1% vs 81.9%)

LADG: Laparoscopy-assisted distal gastrectomy; ODG: Open distal gastrectomy; LC: Laparoscopic gastrectomy; OP: Open gastrectomy; DFS: Disease-free survival; HR: Hazard ratio; LTG: Laparoscopic total gastrectomy; OTG: Open total gastrectomy; LDG: Laparoscopic distal gastrectomy.

Table 2 Studies on laparoscopic surgery in colorectal cancer

Ref.	Study type	Comparison	Group	Endpoints	Results
Bonjer et al[44], 2015	Randomized clinical trial	Laparoscopic vs open surgery for rectal cancer	LC (n = 699); OP (n = 345)	Locoregional recurrence 3 yr after index surgery, and disease-free and overall survival	No significant difference between the two groups in locoregional recurrence 3 yr after index surgery, or disease-free and overall survival (86.7% vs 83.6%)
Fleshman et al[43], ACOSOG Z6051 Randomized Controlled Trial, 2019	Randomized clinical trial	Laparoscopic-assisted resection vs open resection of stage II or III rectal cancer	LC (n = 243); OP (n = 243)	Disease-free survival and local recurrence	No significant difference between the two groups in disease-free survival and local recurrence
Park et al[39], 2020	Multicenter comparative study	Laparoscopic vs open surgery for small T4 colon cancer	LC (n = 149); OP (n = 300)	Blood loss, length of hospital stay, postoperative morbidity, and overall survival or disease-free survival	No significant difference between the two groups in overall survival or disease-free survival, and LC was associated with favorable short-term oncologic outcomes in patients with tumors ≤ 4.0 cm
Li et al[40], 2021	Multicenter comparative study	Laparoscopic vs open surgery for transverse colon cancer	LC (n = 181); OP (n = 235)	Operation time, postoperative hospitalization, lymph node retrieval, 5-yr overall survival	LC was associated with statistically longer operation time (209.96 vs 173.31 min, P = 0.002) and shorter postoperative hospitalization (12.05 vs 14.44 d, P = 0.001), but there was no significant difference in lymph node retrieval and 5-yr overall survival
Garbarino et al[42], 2021	Propensity score-matched analysis	Laparoscopic vs open surgery for rectal resection	LC (n = 181); OP (n = 2 35)	Operative time, postoperative morbidity, hospital stay, safe oncological adequateness	LC was associated with shorter hospital stay (P < 0.001), but there was no significant difference in safe oncological adequateness

LC: Laparoscopic gastrectomy; OP: Open gastrectomy.