Clinical comparison of laparoscopic vs open distal gastrectomy for advanced gastric cancer: Perioperative safety, recovery, and survival

Abstract

BACKGROUND

Total laparoscopic distal gastrectomy (TLDG) is increasingly used for advanced gastric cancer, but its comprehensive outcomes vs open distal gastrectomy (ODG) require further validation.

AIM

To investigate the perioperative safety, postoperative recovery, and mid-term survival between TLDG and ODG for locally advanced gastric cancer.

METHODS

This retrospective study analyzed patients admitted from January 2020 to January 2022. Patients were divided into TLDG and ODG groups on the basis of surgical approach. Perioperative outcomes, postoperative recovery, tumor pathology, preoperative and postoperative day 1 and 5 blood tests, complications, and 3-year overall survival and recurrence-free survival rates were evaluated.

RESULTS

A total of 420 patients were included, with 213 in the TLDG group and 207 in the ODG group. The TLDG group had shorter incision lengths (4.51 ± 0.52 cm vs 17.64 ± 3.25 cm, P < 0.001) and less blood loss (152.44 ± 26.55 mL vs 220.07 ± 21.58 mL, P < 0.001). Postoperative recovery was faster in the TLDG group, with earlier mobilization (1.85 ± 0.22 days vs 2.51 ± 0.24 days, P < 0.001), flatus (2.92 ± 0.24 days vs 3.52 ± 0.21 days, P < 0.001), and lower visual analog scale scores (postoperative day 5: 26.54 ± 4.20 vs 45.51 ± 10.41, P < 0.001). Inflammation was reduced in the TLDG group (postoperative day 1 white blood cell: 11.18 ± 2.11 × 10⁹/L vs 11.81 ± 2.22 × 10⁹/L, P = 0.003). Complication rates were similar, but the ODG group had more grade I–II complications (17.39% vs 10.33%, P = 0.036). Three-year overall survival (90.61% vs 90.34%, P = 0.924) and recurrence-free survival (80.28% vs 81.16%, P = 0.820) showed no significant differences.

CONCLUSION

Compared with ODG, TLDG for locally advanced cancer offers superior short-term outcomes in terms of reduced trauma, accelerated functional recovery, and pain relief without compromising oncological efficacy or survival rates.

Key Words: Totally laparoscopic distal gastrectomy; Open distal gastrectomy; Peri-operative safety; Functional recovery; Gastric cancer; Survival outcomes

Core Tip: This study demonstrates that totally laparoscopic distal gastrectomy for locally advanced gastric cancer provides short-term benefits over open distal gastrectomy, including reduced trauma, less blood loss, faster functional recovery, and lower pain scores, while achieving equivalent mid-term oncological outcomes. The 3-year overall survival and recurrence-free survival rates were comparable between the two techniques. Totally laparoscopic distal gastrectomy is a safe and effective minimally invasive alternative that does not compromise cancer control.

INTRODUCTION

Cancer constitutes a significant global health burden, with adenocarcinoma being the most common histological type[1,2]. Patients often present with non-specific symptoms, leading to locally advanced diagnoses[3]. The standard treatment for locally advanced cancer is surgical resection, with distal gastrectomy and D2 lymph node dissection forming the cornerstone of therapy[4,5]. Recent advancements in minimally invasive surgery have promoted total laparoscopic distal gastrectomy (TLDG) as an alternative to traditional open distal gastrectomy (ODG)[6]. Meta-analyses and large-scale randomized trials have shown that TLDG can achieve oncological outcomes comparable to ODG[7,8]. However, concerns about the oncological adequacy of laparoscopic surgery for advanced cancer, particularly in achieving equivalent lymph node dissection and long-term survival compared with open surgery, have limited its adoption for advanced gastric cancer[9]. The present study aims to compare the perioperative safety, postoperative functional recovery, and survival outcomes of TLDG and ODG in locally advanced cancer.

The pathophysiological progression of cancer involves complex molecular mechanisms, including dysregulation of various cellular signaling pathways[10]. Key pathways, such as those mediated by transforming growth factor β and vascular endothelial growth factor, are associated with tumor invasion, angiogenesis, and metastasis[11,12]. These molecular events support local disease progression and underscore the critical importance of achieving complete and precise surgical resection[13]. The technical nuances of laparoscopic surgery, including its magnified view and fine dissection capabilities, theoretically influence surgical performance and may affect the local biological environment, necessitating detailed comparisons with traditional open surgery[14,15].

This retrospective study aims to evaluate the efficacy of TLDG compared with ODG. The primary objective is to analyze a range of short-term outcomes, including surgical parameters, postoperative pain, functional recovery, inflammatory response, and complication rates. Additionally, this study aims to assess long-term oncological safety by comparing 3-year overall survival and recurrence-free survival rates between the two surgical groups. The novelty of this study lies in its comprehensive analysis of perioperative functional metrics and mid-term survival data in a large patient cohort. The findings are intended to provide robust clinical evidence for surgical decision-making in patients with locally advanced distal cancer.

MATERIALS AND METHODS

Case selection

This retrospective study analyzed data from 420 patients with gastric cancer admitted to Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine from January 2020 to January 2022. Demographic information was gathered through the case report system. Given that this retrospective analysis utilized de-identified patient data, it posed no potential risk to the participants. Thus, informed consent was waived. The waiver and the study protocol were reviewed and approved by Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine Institution’s Ethics Committee, adhering to pertinent regulatory and ethical guidelines.

Inclusion and exclusion criteria

Inclusion criteria: (1) Aged between 18 and 80 years; (2) Histologically confirmed adenocarcinoma of the stomach; (3) Tumors classified as cT2 to cT4a and cN0 to cN1 based on preoperative gastroscopy, endoscopic ultrasound, and/or abdominal computed tomography[16]; (4) Tumors amenable to curative resection via distal gastrectomy; (5) Eastern Cooperative Oncology Group[17] performance status of 0 or 1; (6) American Society of Anesthesiologists[18] physical status classification of I–III; and (7) Completed TLDG or ODG as per the established protocol.

Exclusion criteria: (1) Evidence of potential distant metastasis detected during preoperative evaluations; (2) History of another malignancy within the past 5 years; (3) Previous history of gastric surgery; (4) Gastric cancer-related complications such as complete obstruction or perforation; (5) Prior treatment for gastric cancer, including endoscopic resection, chemotherapy, and/or radiotherapy; and (6) Intraoperative conversion from one surgical procedure to another.

Grouping standards and surgical methods

Patients who underwent totally laparoscopic distal gastrectomy were defined as the laparoscopic group, whereas those who received ODG were defined as the open surgery group. Both groups followed the same preoperative and postoperative examination protocols.

Surgical method for laparoscopic group: The patients underwent general anesthesia, and they were placed in a supine position with legs apart. The surgical field was routinely disinfected and draped. A five-port technique was employed: A 10 mm incision below the umbilicus served as the observation port, through which a trocar was inserted to establish pneumoperitoneum, maintaining pressure at 12-13 mmHg. The primary operating ports were located subcostally on the left anterior axillary line (12 mm) and at the umbilical level on the left midclavicular line (5 mm). The auxiliary operating ports were positioned subcostally on the right midclavian line (5 mm) and at the umbilical level on the right anterior axillary line (12 mm). A 30° laparoscope was inserted to systematically examine the liver, diaphragm, peritoneum, and pelvic cavity for any signs of metastasis. In cases of ascites, samples were directly obtained; in the absence of ascites, 100 mL of normal saline was used to lavage the subdiaphragmatic and peri-gastric areas, with collected fluid sent for cytological examination. Lymph node dissection was performed in accordance with the D2[19] criteria, which involve systematic and complete removal of lymph nodes in the following stations: 1, 3, 4sb, 4d, 5, 6, 7, 8a, 9, 11p, and 12a. The duodenum was transected approximately 3 cm distal to the pylorus by using a linear stapler. Ensuring a proximal margin of ≥ 5 cm from the tumor for infiltrative types or ≥ 3 cm for expansive types, the stomach was transected using a linear stapler, followed by intracorporeal anastomosis. Standardized total laparoscopic anastomosis techniques were employed. For Billroth II anastomosis, the jejunum was transected approximately 20-30 cm distal to the Treitz ligament, and the distal jejunum was pulled up and side-to-side anastomosed with the posterior wall or greater curvature of the gastric remnant by using a linear stapler. A Braun jejunojejunostomy was routinely added. For Roux-en-Y anastomosis, the jejunum was transected distal to the Treitz ligament, and the Roux limb was pulled up and side-to-side or π-shaped anastomosed with the gastric remnant. An additional enteroenterostomy was performed about 45 cm distal to the gastrojejunal anastomosis, and all mesenteric defects were closed by suturing. For Billroth I anastomosis, after the descending duodenum was sufficiently mobilized to ensure no tension, end-to-end gastroduodenal anastomosis was completed using either laparoscopic reverse puncture technique or a circular stapler. The core surgical principle of the chosen anastomotic method is to achieve tension-free and well-vascularized gastrointestinal reconstruction under the premise of ensuring oncological radicality (R0 resection, D2 lymphadenectomy). Before and after each anastomosis was completed, its patency, blood supply, and any torsion were checked. The resected stomach and omentum specimens were placed in a specimen bag. One of the 12 mm ports, typically the one below the umbilicus, was slightly enlarged to about 3-4 cm, through which the specimen was removed under the protection of the specimen bag. The small incision and all ports were then closed layer by layer.

Surgical method for open surgery group: The patients underwent general anesthesia, and they were placed in a supine position. A midline upper abdominal incision, approximately 15-20 cm in length, was made, and the abdominal layers were sequentially opened with the placement of an incision protector. The abdominal cavity was systematically examined to rule out peritoneal seeding, distant metastases, and other signs of advanced disease. The tumor’s location, mobility, and relationship with surrounding organs were determined. Approximately 3 cm from the greater curvature vascular arcade, an electrosurgical knife was used to sequentially divide the right and left gastroepiploic vessels up to the predetermined resection line. The hepatogastric ligament was opened, and the right gastric artery was divided. The left gastric vessels were then divided upwards. In cases of ascites, samples were directly obtained; in the absence of ascites, 100 mL of normal saline was used to lavage the subdiaphragmatic and peri-gastric areas, with collected fluid sent for cytological examination. Lymph node dissection was performed in accordance with the D2[19] criteria, which involve systematic and complete removal of lymph nodes in the following stations: 1, 3, 4sb, 4d, 5, 6, 7, 8a, 9, 11p, and 12a. The duodenum was transected approximately 3 cm distal to the pylorus. Ensuring a proximal margin of at least 3-5 cm from the tumor edge, the stomach was transected, and the specimen was removed. Gastrointestinal anastomosis was performed within the abdominal cavity. The abdominal wall incision was closed layer by layer.

Postoperative follow-up

After surgery, the patients were regularly followed up in accordance with the same protocol. Data, including recurrence and mortality, were recorded. The follow-up schedule was as follows: Every 3 months for the first 2 years and then every 6 months for the subsequent 1 year. The total follow-up period for this study was 3 years. Follow-up assessments included physical examinations, laboratory tests, and imaging studies.

Observation indicators and data collection

Visual analog scale: Postoperative pain levels were evaluated using visual analog scale (VAS). The total score ranges from 0 (no pain) to 100 (extremely severe pain)[20], with higher scores indicating more severe pain. This scale demonstrates excellent intraclass correlation coefficient (ICC) reliability, with an ICC value of 0.97[21]. This high ICC value suggests that VAS is a reliable tool for measuring postoperative pain.

Postoperative complications: The severity of all complications was uniformly assessed using the Clavien-Dindo classification[22], with higher grades indicating more severe complications. Grade I refers to any deviation from the normal postoperative course without the need for pharmacological treatment or surgical, endoscopic, and radiological interventions. Grade II refers to complications requiring pharmacological treatment with drugs other than those allowed for grade I complications. Grade III involves complications requiring surgical, endoscopic, or radiological intervention. Grade IV includes life-threatening complications (including central nervous system complications) requiring intensive care units management. Grade V indicates death of a patient.

Preoperative and postoperative blood testing: The patients underwent blood tests before and after surgery. After fasting, 10 mL of venous blood was collected in the morning on an empty stomach. White blood cell (WBC) count and platelet count: Blood (2 mL) was placed in an ethylenediaminetetraacetic acid anticoagulant tube, mixed thoroughly, and loaded into the instrument. WBC and platelet counts were automatically calculated using the impedance method by a fully automated hematology analyzer (DH-800 CS, Shenzhen Dimai Biotechnology Co., Ltd., China). Hemoglobin (Hb) measurement: Blood (2 mL) was added to an ethylenediaminetetraacetic acid anticoagulant tube and gently inverted to mix. An appropriate amount of blood was added to cyanmethaemoglobin reagent at a dilution ratio of 1:200. After the mixture was thorough mixed, the absorbance was measured at 540 nm by using a spectrophotometer (Nano Drop Eight, Shenzhen Dimai Biotechnology Co., Ltd., China). The Hb concentration was then calculated on the basis of a standard curve or formula. Total bilirubin measurement: Blood (3 mL) was collected in a tube without anticoagulant and centrifuged (DT4-6C, Beijing Shidaibilin Centrifuge Co., Ltd., China) to separate the serum. An appropriate amount of serum was added to diazo reagent at a dilution ratio of 1:10. The sample and reagent were thoroughly mixed, and the absorbance was measured at 546 nm using a spectrophotometer. The total bilirubin concentration was calculated on the basis of a standard curve or formula. Amylase measurement: After centrifugation to separate the serum, an appropriate amount of serum was diluted with buffer solution at a ratio of 1:10. The diluted sample was mixed with starch solution and incubated at 37 °C for 10 minutes. Glucose oxidase and other auxiliary enzymes were added, and the mixture was further incubated for 5 minutes. The absorbance was measured at 405 nm by using a spectrophotometer, and the amylase activity was calculated on the basis of a standard curve.

Survival outcomes: At the end of the 3-year follow-up period, the mortality and overall survival rates were recorded in accordance with the follow-up data. The 3-year recurrence-free survival rate was calculated from the date of surgery to the date of recurrence detection or death from any cause.

Detailed description of survival outcomes: This includes deaths from any cause. Three-year overall survival rate: The proportion of patients surviving over the entire follow-up period was calculated. This metric provides an overview of the general survival outcomes for the patient cohort. Three-year recurrence-free survival rate: This rate is defined as the time from the date of surgery to either the date of recurrence detection or the date of death from any cause, whichever occurs first. Patients who did not experience recurrence or death within the 3-year follow-up period were censored at the end of the study[23].

Statistical analysis

Data analysis was conducted using SPSS (version 29.0) statistical software (SPSS Inc., Chicago, IL, United States). Categorical data were represented in the format n (%). χ² test was utilized when the sample size was ≥ 40 and the theoretical frequency (T) was ≥ 5, with the test statistic denoted as χ². If the sample size was ≥ 40 but the T fell within the range of 1 ≤ T < 5, χ² test was adjusted using a correction formula. For sample sizes < 40 or theoretical frequencies T < 1, statistical analysis was performed using Fisher’s exact probability method. For normally distributed continuous data, the results were presented as (mean ± SD), and t-test was employed for comparison. P < 0.05 was considered statistically significant.

Given that this study employed a retrospective design, post-hoc power analysis was conducted to verify the adequacy of the sample size to ensure that the number of cases included was sufficient to support the statistical power of the research conclusions. The sample size estimation for binary variables was based on the differences in postoperative complication rates, assuming a moderate effect size d = 0.5 and a two-tailed significance level α = 0.05. The calculation using G*Power software showed that at least 152 cases per group were required. In actuality, 213 cases (TLDG) and 207 cases (ODG) were enrolled, thus meeting and exceeding the required sample size.

RESULTS

Baseline demographic and clinical characteristics

In terms of baseline demographic and clinical characteristics, the two groups showed similar results in age, American Society of Anesthesiologists score, Eastern Cooperative Oncology Group score, proportion of comorbidities, and history of previous abdominal surgery (all P > 0.05, Table 1). These results indicate that the laparoscopic surgery group and the open surgery group are highly comparable in several important baseline characteristics, providing a solid foundation for subsequent analyses.

Table 1 Baseline demographic and clinical characteristics, n (%)/mean ± SD.

Parameters	Laparoscopy (n = 213)	Open surgery (n = 207)	t/χ2	P value
Age (years)	59.54 ± 6.12	59.58 ± 6.47	0.071	0.943
Gender			0.163	0.687
Male	152 (71.36)	144 (69.57)
Female	61 (28.64)	63 (30.43)
Body mass index (kg/m²)	23.55 ± 2.41	23.70 ± 2.54	0.635	0.525
ASA score			0.165	0.921
I	102 (47.89)	101 (48.79)
II	100 (46.95)	97 (46.86)
III	11 (5.16)	9 (4.35)
ECOG			0.067	0.796
0	184 (86.38)	177 (85.51)
1	29 (13.62)	30 (14.49)
Comorbidity	95 (44.6)	93 (44.93)	0.005	0.946
Previous abdominal operation	32 (15.02)	28 (13.53)	0.192	0.661
Clinical T stage			0.112	0.946
T2	91 (42.72)	86 (41.55)
T3	81 (38.03)	82 (39.61)
T4a	41 (19.25)	39 (18.84)
Clinical N stage			0.287	0.592
N0	94 (44.13)	86 (41.55)
N1	119 (55.87)	121 (58.45)
Clinical tumor-node-metastasis stage			0.643	0.886
I	58 (27.23)	50 (24.15)
IIA	33 (15.49)	36 (17.39)
IIB	36 (16.9)	36 (17.39)
III	86 (40.38)	85 (41.06)

ASA: American Society of Anesthesiology score; I: Normal and healthy patients; II: Patients with mild systemic diseases but no functional limitations; ECOG: Eastern Cooperative Oncology Group; 0: The activity ability is completely normal, with no symptoms or signs; 1: Can move freely and engage in light physical activities, including general household or office work, but cannot engage in heavier physical activities; Clinical T stage: T2: Tumor invades the intrinsic muscle layer; T3: Tumor penetrates the subserosal layer; T4a: Tumor invades the serosa (visceral peritoneum); Clinical N stage: N0: No regional lymph node metastasis; N1: There are 1 to 2 regional lymph node metastases; Clinical tumor-node-metastasis stage: I: Early gastric cancer, with tumor localization and no lymph node metastasis or only a small amount of lymph node metastasis; IIA and IIB: Locally advanced gastric cancer, the tumor may have invaded deeper tissue layers, and the number of lymph node metastases has increased, but distant metastases have not yet appeared; III: Locally advanced gastric cancer, the tumor may have invaded the serosal layer or adjacent organs, accompanied by significant lymph node metastasis.

Postoperative related indicators

In terms of perioperative outcomes, the incision length in the laparoscopic group was significantly shorter than that in the open surgery group (P < 0.001), indicating that laparoscopic surgery is less invasive (Table 2). The operative time in the laparoscopic group was significantly longer than that in the open surgery group (P < 0.001), suggesting that laparoscopic surgery may require more time to complete. Additionally, intraoperative blood loss was significantly lower in the laparoscopic group than in the open surgery group (P < 0.001), further demonstrating the advantage of laparoscopic surgery in reducing bleeding. Meanwhile, no significant differences were found between the two groups regarding the extent of resection and the degree of lymph node dissection. The proportions of distal gastrectomy and total gastrectomy were similar between the two groups (P = 0.797), and the proportion of D2 lymph node dissection was very close (P = 0.493). The proximal margin distance and R0 resection rate showed no significant differences between the two groups (P > 0.05). Similarly, no significant difference was noted in the distribution of anastomotic methods between the two groups (P = 0.709). These results suggest that laparoscopic surgery has clear advantages in reducing trauma and bleeding, but it may involve slightly higher surgical complexity and longer operative times.

Table 2 Perioperative outcomes, n (%)/mean ± SD.

Parameters	Laparoscopy (n = 213)	Open surgery (n = 207)	t/χ2	P value
Incision length (cm)	4.51 ± 0.52	17.64 ± 3.25	57.358	< 0.001
Operation time (minutes)	227.01 ± 54.08	164.41 ± 45.89	12.803	< 0.001
Blood loss (mL)	152.44 ± 26.55	220.07 ± 21.58	28.680	< 0.001
Extent of resection			0.066	0.797
Distal gastrectomy	207 (97.18)	202 (97.58)
Total gastrectomy	6 (2.82)	5 (2.42)
Extent of lymphadenectomy			None	0.493
< D2	0 (0.00)	1 (0.48)
D2	213 (100.00)	206 (99.52)
Proximal resection margin (cm)	5.27 ± 1.76	5.05 ± 1.63	1.320	0.188
R0 resection	206 (96.71)	196 (94.69)	1.052	0.305
Anastomosis			0.687	0.709
Billroth I	76 (35.68)	66 (31.88)
Billroth II	115 (53.99)	119 (57.49)
Roux-en-Y	22 (10.33)	22 (10.63)

Regarding postoperative functional recovery, the two groups demonstrated significant differences (Figure 1). The laparoscopic group had significantly earlier times to first ambulation than the open surgery group (P < 0.001), indicating that patients who underwent laparoscopic surgery were able to recover their mobility more quickly. The time to first flatus was significantly earlier in the laparoscopic group than in the open surgery group (P < 0.001), suggesting that laparoscopic surgery facilitates faster recovery of gastrointestinal function. The time to first oral intake was earlier in the laparoscopic group than in the open surgery group (P < 0.001). No significant difference was found in postoperative hospital stay between the two groups (P = 0.969). The frequency and dosage of analgesic use were significantly lower in the laparoscopic group than in the open surgery group (P < 0.001), suggesting less postoperative pain after laparoscopic surgery. The VAS results showed that the pain scores on the first and fifth postoperative days were significantly lower in the laparoscopic group than in the open surgery group (P < 0.001), further confirming the advantage of laparoscopic surgery in reducing postoperative pain. In summary, laparoscopic surgery demonstrated significant advantages in promoting early ambulation, restoring gastrointestinal function, and alleviating postoperative pain, although no significant difference was found in postoperative hospital stay.

Figure 1 Postoperative functional recovery. A: First event; B: Postoperative hospital stay (day); C: Times analgesic given (times); D: Dose of analgesic (mg); E: Visual analog scale scores (point). ^cP < 0.001. POD: Postoperative day; VAS: Visual analog scale.

The postoperative tumor pathology results showed that the average tumor size was similar between the two groups, and the number of resected or metastatic lymph nodes had no significant differences (all P > 0.05, Table 3). In terms of histological type and pathological stage, no significant differences were observed between the two groups (all P > 0.05). The high consistency in various postoperative tumor pathology indicators between laparoscopic surgery and open surgery indicated that the two surgical methods are comparable in terms of tumor resection effectiveness.

Table 3 Postoperative oncological pathology results, n (%)/mean ± SD.

Parameters	Laparoscopy (n = 213)	Open surgery (n = 207)	t/χ2/Fisher	P value
Mean tumor size (cm)	4.64 ± 0.95	4.63 ± 0.89	0.062	0.951
Mean number of retrieved lymph nodes			None	0.493
≥ 16 nodes	213 (100.00)	206 (99.52)
< 16 nodes	0 (0.00)	1 (0.48)
Number of metastatic lymph nodes (number)	3.54 ± 0.61	3.48 ± 0.57	1.054	0.293
Histology			0.950	0.622
Differentiated	85 (39.91)	80 (38.65)
Undifferentiated	124 (58.22)	120 (57.97)
Other	4 (1.88)	7 (3.38)
Pathologic T stage			0.494	0.920
T1	59 (27.70)	54 (26.09)
T2	45 (21.13)	48 (23.19)
T3	57 (26.76)	58 (28.02)
T4	52 (24.41)	47 (22.71)
Pathologic N stage			0.005	0.944
N0	96 (45.07)	94 (45.41)
N+	117 (54.93)	113 (54.59)
Pathologic tumor-node-metastasis stage			1.099	0.577
I	77 (36.15)	71 (34.30)
II	64 (30.05)	72 (34.78)
III	72 (33.80)	64 (30.92)

Pathologic T stage: T1: Tumor invasion of mucosal layer or submucosal layer; T2: Tumor invades the intrinsic muscle layer; T3: Tumor penetrates the subserosal layer; T4: Tumor invades deeper or adjacent organs/structures; Pathologic N stage: N0: No cancer cells were found to have spread to regional lymph nodes; N+: There is evidence to suggest that cancer cells have spread to one or more regional lymph nodes; Pathologic tumor-node-metastasis stage: I: Cancer is limited to the gastric wall or only slightly extends to adjacent structures, and no lymph node or distant metastasis has been found; II: Cancer may have spread to deeper layers of the gastric wall or adjacent structures, and may involve a small amount of lymph node metastasis, but no distant metastasis; III: Cancer significantly extends to the deep or adjacent structures of the gastric wall, accompanied by more lymph node metastasis, but there is still no distant metastasis.

The preoperative blood test results, including WBC, Hb, platelet count, total bilirubin, and amylase levels, showed no significant differences between the laparoscopic surgery group and the open surgery group (all P > 0.05), indicating that the two groups were comparable in terms of baseline blood indicators (Table 4). On the first postoperative day, the WBC level was significantly higher in the open surgery group than in the laparoscopic group (P = 0.003), suggesting that open surgery may trigger a more pronounced inflammatory response. In terms of Hb, platelet count, total bilirubin, and amylase levels, no significant differences were observed between the two groups on the first postoperative day (all P > 0.05). On the fifth postoperative day, the Hb level was significantly higher in the laparoscopic group than in the open surgery group (P = 0.013), indicating that laparoscopic surgery has a lesser effect on anemia in patients. Meanwhile, the open surgery group had a significantly higher platelet count than the laparoscopic group (P = 0.046), suggesting that open surgery may lead to a longer recovery period for platelet counts. In terms of WBC, total bilirubin, and amylase levels, no significant differences were found between the two groups on the fifth postoperative day (all P > 0.05). The open surgery group exhibited higher WBC counts on the first postoperative day and higher platelet counts on the fifth postoperative day. These results suggest that laparoscopic surgery has potential advantages in reducing inflammatory responses and maintaining Hb levels.

Table 4 Postoperative blood test results, mean ± SD.

Parameters	Laparoscopy (n = 213)	Open surgery (n = 207)	t	P value
WBC (× 109/L)
Preop	6.72 ± 1.14	6.71 ± 1.07	0.096	0.924
POD1	11.18 ± 2.11	11.81 ± 2.22	2.978	0.003
POD5	7.15 ± 2.51	7.20 ± 2.70	0.209	0.835
Hb (g/dL)
Preop	13.44 ± 2.01	13.30 ± 2.04	0.709	0.479
POD1	12.15 ± 1.64	11.89± 1.81	1.546	0.123
POD5	11.51 ± 1.41	11.14 ± 1.61	2.490	0.013
Platelet (× 109/L)
Preop	257.39 ± 66.51	258.28 ± 63.91	0.139	0.889
POD1	208.24 ± 51.99	217.14 ± 53.85	1.723	0.086
POD5	240.01 ± 66.64	253.44 ± 70.84	2.002	0.046
Total bilirubin (mg/dL)
Preop	0.76 ± 0.21	0.77 ± 0.24	0.143	0.887
POD1	0.91 ± 0.23	0.92 ± 0.26	0.278	0.781
POD5	0.84 ± 0.25	0.83 ± 0.26	0.224	0.823
Amylase (U/dL)
Preop	73.21 ± 20.68	71.42 ± 20.13	0.902	0.368
POD1	137.21 ± 33.41	133.59 ± 35.77	1.071	0.285
POD5	92.34 ± 26.51	91.35 ± 20.81	0.429	0.668

WBC: White blood cell count; POD: Postoperative day; Hb: Hemoglobin.

Patient condition during follow-up period

Comparing the incidence of postoperative complications showed that most surgery-related complications, such as wound complications, intra-abdominal fluid collection or abscess, intra-abdominal hemorrhage, ileus, anastomotic stricture, anastomotic leak, and pancreatitis/pancreatic fistula, did not differ significantly between the two groups (all P > 0.05, Table 5). The incidence of ileus in the laparoscopic group was slightly lower than in the open surgery group, but it did not reach statistical significance (P = 0.069). For gastrointestinal functional complications and systemic complications, including delayed gastric emptying, reflux symptoms, postgastrectomy syndrome, pulmonary complications, urinary tract complications, renal insufficiency, hepatic insufficiency, and cardiac complications, no significant differences were observed between the two groups (all P > 0.05). Notably, the total number of early and late complications graded as Clavien-Dindo I or II was significantly lower in the laparoscopic group than in the open surgery group (P = 0.036). However, no significant difference was observed in more severe complications graded ≥ III (P = 0.212). Additionally, no significant differences were found between the two groups in terms of re-admission rates and 90-day mortality rates (all P > 0.05). These results suggest that while laparoscopic surgery shows some advantages in certain minor complications, the overall severity of complications and major clinical outcomes are comparable between the two surgical approaches.

Table 5 Postoperative complications, n (%).

Parameters	Laparoscopy (n = 213)	Open surgery (n = 207)	χ2/Fisher	P value
Surgery related complications
Wound complications	11 (5.16)	15 (7.25)	0.784	0.376
Intraabdominal fluid collection or abscess	6 (2.82)	11 (5.31)	1.685	0.194
Intraabdominal hemorrhage	1 (0.47)	4 (1.93)	0.869	0.351
Intraluminal hemorrhage	1 (0.47)	1 (0.48)	0.000	1.000
Intestinal obstruction	7 (3.29)	15 (7.25)	3.317	0.069
Anastomotic stricture	0 (0.00)	1 (0.48)	None	0.493
Anastomotic leak	4 (1.88)	2 (0.97)	0.141	0.707
Pancreatitis/pancreatic fistula	4 (1.88)	1 (0.48)	0.753	0.386
Gastrointestinal functional complications
Delayed gastric emptying	1 (0.47)	2 (0.97)	0.001	0.980
Reflux symptoms	0 (0.00)	1 (0.48)	None	0.493
Postgastrectomy syndrome	0 (0.11)	1 (0.48)	None	0.493
Systemic complications
Pulmonary complications	5 (2.35)	6 (2.90)	0.125	0.724
Urinary tract complications	2 (0.94)	1 (0.48)	0.000	1.000
Renal insufficiency	1 (0.47)	0 (0.00)	None	1.000
Hepatic insufficiency	1 (0.47)	2 (0.97)	0.001	0.980
Cardiac complications	0 (0.00)	1 (0.48)	None	0.493
Others	6 (2.82)	8 (3.86)	0.358	0.550
Total Clavien-Dindo complication grade of early and late complications
I or II	22 (10.33)	36 (17.39)	4.399	0.036
≥ III	17 (7.98)	24 (11.59)	1.556	0.212
Readmission	8 (3.76)	9 (4.35)	0.095	0.758
90 days mortality rate	1 (0.47)	1 (0.48)	0.000	1.000

The 3-year overall survival rate was not significantly different between the two groups (P = 0.924), indicating that the two surgical methods have similar long-term survival outcomes (Figure 2). Similarly, the 3-year recurrence-free survival rate showed no significant difference between the two groups (P = 0.820), suggesting that laparoscopic surgery and open surgery are equally effective in preventing disease recurrence.

Figure 2 Survival outcomes.

DISCUSSION

This comparative study demonstrated that TLDG is a feasible and safe treatment for locally advanced cancer, offering clear short-term advantages over ODG while achieving equivalent mid-term oncological outcomes. The study provides valuable insights into the relative merits and limitations of minimally invasive surgery compared with the traditional open surgery in this challenging disease setting.

A notable observation concerns the invasiveness of the two surgical techniques. Analysis of perioperative parameters showed consistency with the inherent characteristics of laparoscopic surgery[24]. Prolonged operative time is a common phenomenon in TLDG due to the technical complexity of intracorporeal dissection and anastomosis[25]. However, this extended duration does not appear to compromise patient safety. The reduction in intraoperative blood loss observed in the TLDG group highlights a key advantage of laparoscopic surgery. The magnified view and precise dissection capabilities of laparoscopic surgery may contribute to enhanced identification and control of the vascular system[26]. The shorter skin incision translates into reduced tissue trauma, minimizing blood loss[27]. This finding is consistent with the well-documented benefits of laparoscopic surgery in abdominal procedures, where the magnified view and precise instrument handling facilitate meticulous dissection while preserving surrounding structures[28].

This study aims to compare the comprehensive outcomes of TLDG and ODG approaches. A notable detail that the specific technical pathways to achieve the same therapeutic goals differ between the two approaches. TLDG relies on intracorporeal anastomosis using laparoscopic instruments (such as side-to-side or π-shaped anastomosis), whereas ODG involves manual suturing or stapling under direct vision[29]. These technical differences are inherent attributes of the two approaches. The standardized technique used in TLDG adheres to the same core principles as open surgery: Ensuring oncological radicality and achieving tension-free, well-vascularized gastrointestinal reconstruction. Therefore, despite differences in operative methods and techniques, both groups share comparable fundamental therapeutic goals and key quality indicators. This forms a reasonable basis for subsequent comparisons of oncological and functional outcomes.

Postoperative functional recovery has emerged as a clear advantage of minimally invasive techniques. Patients who underwent TLDG experienced earlier mobilization, faster recovery of gastrointestinal motility, and earlier resumption of oral intake. These benefits are likely multifactorial. Reduced abdominal wall trauma decreases postoperative pain. Smaller incisions result in less pain and muscle damage, promoting earlier mobilization, which, in turn, reduces the risk of pulmonary complications[30]. Additionally, minimizing disruption to bowel integrity and reducing the inflammatory response may contribute to faster recovery of gastrointestinal motility[31]. Lower analgesic consumption and lower VAS scores further support the notion that laparoscopic surgery provides a more comfortable postoperative course. Pain relief is a key clinical outcome that facilitates deep breathing, coughing, and early ambulation, potentially mitigating pulmonary complications and thromboembolic events[29]. These observations are consistent with previous randomized trials and meta-analyses that reported accelerated functional recovery in the early and late phases after laparoscopic gastrectomy[32]. These notable advantages in functional recovery did not translate into shortened postoperative hospital stays, which may be influenced by social factors or cautious discharge practices following major oncological surgery[33].

Hematological parameters provide a biochemical perspective on the body’s response to surgical trauma. The reduced bleeding burden may contribute to the more favorable early inflammatory response observed in the laparoscopic cohort, evidenced by decreased postoperative WBC counts[34]. The higher WBC count in the ODG group on the first postoperative day suggests a more pronounced systemic inflammatory response due to the inherent greater tissue damage associated with open surgery. The maintenance of higher Hb levels in the TLDG group on the fifth postoperative day further supports the importance of reduced physiological insult, indicating either less initial blood loss or more effective recovery of red blood cell production[35]. The transiently increased platelet count in the ODG group can be interpreted as part of a more robust acute-phase response[36]. These differences reinforce the concept that laparoscopic surgery induces less pronounced physiological disturbances, which may underlie the observed clinical benefits in functional recovery[37].

The most critical issue in oncological surgery is the completeness of resection. This study demonstrated that the extent of lymph node dissection are comparable between the two methods. The equal average tumor size, the number of retrieved lymph nodes, and the number of metastatic lymph nodes between the two groups confirmed that the laparoscopic approach does not compromise the integrity of cancer resection. The ability to consistently perform D2 lymph node dissection in all laparoscopic cases, achieving lymph node yields that meet oncological standards, is a key finding[38]. Previous studies have shown that TLDG can achieve lymph node dissection and margin status comparable to open surgery[39]. This eliminates early concerns that laparoscopic surgery may be insufficient for the meticulous lymph node dissection required in cancer surgery. The comparable distribution of histological types and final pathological tumor-node-metastasis stages between the two groups further strengthens the validity of the comparison, indicating that both techniques are suitable for patient cohorts with similar disease burdens.

A comprehensive assessment of complications is crucial for an overall evaluation. The overall incidence of early and late complications for TLDG and ODG was statistically similar. This reassuring finding indicates that laparoscopic surgery does not introduce new or unique risks. A deeper analysis using the Clavien-Dindo classification revealed a subtle detail: The incidence of grade I-II complications was significantly higher in the open surgery group. These mild-to-moderate complications are typically associated with surgical wounds or minor systemic issues, which logically align with the consequences of larger abdominal incisions[40]. The incidence of severe complications (grade III and above) was equivalent, confirming the technical safety of TLDG. The equivalence in 90-day mortality and readmission rates further supports the conclusion that TLDG is a safe alternative to perioperative ODG.

Long-term survival rates are a crucial metric in cancer surgery[41]. The differences in 3-year overall survival and recurrence-free survival further reinforce the oncological equivalence of these two techniques. The short-term benefits of laparoscopic surgery do not come at the expense of long-term tumor efficacy, indicating that the minimally invasive approach does not compromise long-term disease control, a conclusion consistent with the results of large-scale prospective trials reporting non-inferior survival rates following laparoscopic gastrectomy for locally advanced tumors[42].

The findings of the present study were compared with those of the large randomized trial KLASS-02, which established the non-inferiority of laparoscopic treatment for locally advanced gastric cancer[43]. The results of the present study validated its core conclusions. Similar survival rates and comparable R0 resection rates support the oncological safety of laparoscopic surgery. Additionally, this study refines these findings. The higher rate of minor complications in the open surgery group specifies the complication advantages of laparoscopic surgery. Furthermore, the systematic evaluation of postoperative pain, inflammation, and rapid recovery after total laparoscopic surgery provides an important supplement to this high-level evidence from the perspective of perioperative recovery quality.

Despite these encouraging results, this study has several limitations that must be acknowledged. First, its retrospective and single-center design introduces the possibility of selection bias and limits the generalizability of the findings. Although baseline characteristics were balanced, unmeasured confounding factors may persist. Second, while the follow-up period was extended to 3 years, it may still be insufficient to capture late recurrences or long-term functional sequelae that may emerge beyond this timeframe. Finally, subjective measures, such as pain scores and functional milestones, may introduce information bias. Future studies should focus on prospective, multi-institutional randomized trials with longer follow-up periods to validate these findings. Incorporating robust quality-of-life assessments and cost-effectiveness analyses could provide a more comprehensive evaluation of the value of laparoscopic gastrectomy. Additionally, investigating the role of enhanced recovery after surgery protocols specifically tailored for laparoscopic cancer surgery can help maximize its benefits. Exploring the molecular correlates of the different inflammatory responses observed between these two methods may also provide deeper insights into cancer biology and recurrence risk.

CONCLUSION

This analysis indicates that compared with the traditional open approach for treating locally advanced cancer, TLDG offers clear perioperative and functional advantages without compromising oncological safety. The equivalence in long-term survival outcomes, combined with reduced trauma, decreased inflammatory response, and accelerated recovery, makes laparoscopic surgery a viable option.