Well-designed retrospective study versus small-sample prospective study in research based on laparoscopic and open radical distal gastrectomy for advanced gastric cancer

Laparoscopic versus open distal gastrectomy for advanced gastric cancer in elderly patients: a propensity-score matched analysis

BACKGROUND

Scarce research has reported the efficacy and safety of laparoscopic distal gastrectomy in elderly patients. This retrospective study aimed to compare the outcomes of laparoscopic and open distal gastrectomy for advanced gastric cancer in elderly patients.

METHODS

A total of 303 elderly patients who underwent distal gastrectomy for advanced gastric cancer from June 2017 to June 2021 were enrolled. Variables used to calculate propensity score matching included sex, age, body mass index, American Society of Anesthesiologists, history of diabetes, and history of hypertension. The statistical significance of continuous variables was tested using an independent sample t test. chi-square or Fisher's exact tests were used for categorical variables. Kaplan-Meier curve and log-rank test were used for the evaluation of 3-year overall survival and recurrence-free survival.

RESULTS

After performing 1:1 propensity score matching, 248 patients were included for analysis (laparoscopic = 124, open = 124). Compared with the open group, the laparoscopic group showed significant advantages in estimated blood loss (P < 0.001), pain scale on the first postoperative day (P = 0.002), time to first flatus (P = 0.004), time to first liquid diet (P = 0.005), hospital stays (P < 0.001), and total complications (P = 0.011), but devoted much more operation time (P < 0.001). No statistical difference was observed between the two groups in 3-year recurrence-free survival (P = 0.315) or overall survival (P = 0.159).

CONCLUSIONS

Our analysis demonstrated that laparoscopic surgery had the advantages of less intraoperative blood loss, fewer postoperative complications, and faster postoperative recovery in distal gastrectomy for advanced gastric, indicating that laparoscopic distal gastrectomy is safe and effective for treating elderly patients with distal gastric cancer.

Comparison of robotic versus laparoscopic versus open distal gastrectomy for locally advanced gastric cancer: a prospective trial-based economic evaluation

IMPORTANCE

It is largely unclear whether robotic distal gastrectomy (RDG) is cost-effective for locally advanced gastric cancer (LAGC).

OBJECTIVE

To evaluate the cost-effectiveness of RDG, laparoscopic distal gastrectomy (LDG), and open distal gastrectomy (ODG) for patients with LAGC.

DESIGN, SETTING, AND PARTICIPANTS

Inverse probability of treatment weighting (IPTW) was used to balance baseline characteristics. A decision-analytic model was constructed to evaluate the cost-effectiveness of RDG, LDG, and ODG.

EXPOSURES

RDG, LDG, and ODG.

MAIN OUTCOMES AND MEASURES

Incremental cost-effectiveness ratio (ICER) and quality-adjusted life year (QALY).

RESULTS

This pooled analysis of two randomized controlled trials included 449 patients: 117, 254, and 78 patients in the RDG, LDG, and ODG groups, respectively. After IPTW, RDG demonstrated its priority in terms of less blood loss, postoperative length, and complication rate (all P < 0.05). RDG also showed higher QOL with more cost, representing an ICER of $85,739.73 per QALY and $42,189.53 per QALY compared to LDG and ODG, respectively. In probabilistic sensitivity analysis, RDG achieved the best cost-effectiveness for patients with LAGC only when the willingness-to-pay threshold was > $85,739.73 per QALY, which significantly exceeded 3 times Chinese per capita GDP. Furthermore, one of the most important factors was the indirect costs of robotic surgery in terms of the cost-effectiveness of RDG compared to that of LDG or ODG.

CONCLUSIONS AND RELEVANCE

Although improved short-term outcomes and QOL were seen in patients underwent RDG, the economic burden should be considered in the clinical decision-making regarding robotic surgery use for patients with LAGC. Our findings may vary in different health care settings and affordability. Trial registration CLASS-01 trial (ClinicalTrials.gov, CT01609309) and FUGES-011 trial (ClinicalTrials.gov, NCT03313700).

Laparoscopic vs Open Distal Gastrectomy for Locally Advanced Gastric Cancer: 5-Year Outcomes of the KLASS-02 Randomized Clinical Trial

Question

What is the oncologic safety profile of laparoscopic distal gastrectomy for the treatment of clinically advanced gastric cancer in terms of 5-year survival?

Findings

In this randomized clinical trial of 1050 patients, in patients who underwent laparoscopic or open distal gastrectomy, the 5-year overall survival rates (88.9% vs 88.7%) and relapse-free survival rates (79.5% vs 81.1%) did not differ significantly. The late complication rate was significantly lower in the laparoscopic group than in the open group (6.5% vs 11.0%).

Meaning

The 5-year follow-up results of the Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS)-02 trial support the rationale for laparoscopic surgery in patients with locally advanced gastric cancer.

Importance

The long-term safety of laparoscopic distal gastrectomy for locally advanced gastric cancer (AGC) remains uncertain given the lack of 5-year follow-up results.

Objective

To compare the 5-year follow-up results in patients with clinically AGC enrolled in the Korean Laparoendoscopic Gastrointestinal Surgery Study (KLASS)-02 randomized clinical trial who underwent laparoscopic or open distal gastrectomy.

Design, Setting, and Participants

The KLASS-02, a multicenter randomized clinical trial, showed that laparoscopic surgery was noninferior to open surgery for patients with locally AGC. The present study assessed the 5-year follow-up results, including 5-year overall survival (OS) and relapse-free survival (RFS) rates and long-term complications, in patients enrolled in KLASS-02. From November 21, 2011, to April 29, 2015, patients aged 20 to 80 years diagnosed preoperatively with locally AGC were enrolled. Final follow-up was on June 15, 2021. Data were analyzed June 24 to September 9, 2021.

Interventions

Patients were treated with R0 resection either by laparoscopic gastrectomy or open gastrectomy as the full analysis set of the KLASS-02 trial.

Main Outcomes and Measures

Five-year OS and RFS rates, recurrence patterns, and long-term surgical complications were evaluated.

Results

This study enrolled a total of 1050 patients. A total of 974 patients were treated with R0 resection; 492 (50.5%) in the laparoscopic gastrectomy group (mean [SD] age, 59.8 [11.0] years; 351 men [71.3%]) and 482 (49.5%) in the open gastrectomy group (mean [SD] age, 59.4 [11.5] years; 335 men [69.5%]). In patients who underwent laparoscopic and open distal gastrectomy, the 5-year OS (88.9% vs 88.7%) and RFS (79.5% vs 81.1%) rates did not differ significantly. The most common types of recurrence were peritoneal carcinomatosis (73 of 173 [42.1%]), hematogenous metastases (36 of 173 [20.8%]), and locoregional recurrence (23 of 173 [13.2%]), with no between-group differences in types of recurrence at each cancer stage. The correlation between 3-year RFS and 5-year OS at the individual level was highest in patients with stage III gastric cancer (ρ = 0.720). The late complication rate was significantly lower in the laparoscopic than in the open surgery group (32 of 492 [6.5%] vs 53 of 482 [11.0%]). The most common type of complication in both groups was intestinal obstruction (13 of 492 [2.6%] vs 24 of 482 [5.0%]).

Conclusions and Relevance

The 5-year outcomes of the KLASS-02 trial support the 3-year results, which is the noninferiority of laparoscopic surgery compared with open gastrectomy for locally AGC. The laparoscopic approach can be recommended in patients with locally AGC to achieve the benefit of low incidence of late complications.

Trial Registration

ClinicalTrials.gov Identifier: NCT01456598

Comparison of estimated treatment effects between randomized controlled trials, case-matched, and cohort studies on laparoscopic versus open distal gastrectomy for advanced gastric cancer: a systematic review and meta-analysis

PURPOSE

In actual surgical research, case-matched studies are frequently conducted as an alternative to randomized controlled trials (RCTs). However, it is still unclear what differences there are between RCTs and case-matched studies in upper gastrointestinal surgery, and clarifying them is a very important clinical issue. Thus, the purpose of this study was to investigate estimated treatment effects between RCTs, case-matched studies, and cohort studies regarding laparoscopic distal gastrectomy (LDG) for advanced gastric cancer (AGC).

METHODS

We searched the PubMed, Cochrane Central Register of Controlled Trials, and Web of Science databases for studies that compared LDG versus open distal gastrectomy for AGC published from the inception of the databases until July 2021. A meta-analysis was performed using the Review Manager version 5.3 software program from the Cochrane Collaboration, and six short-term outcomes and three long-term outcomes were assessed.

RESULTS

Twenty-three studies with 13698 patients were included. There was no difference in estimated treatment effects between RCTs and case-matched studies for all outcomes except for the number of retrieved lymph nodes and postoperative complications. In terms of intraoperative blood loss, postoperative hospital stay, number of retrieved lymph nodes, and recurrence, observational studies tended to overestimate the treatment effects.

CONCLUSION

The estimated treatment effects of LDG for AGC in the case-matched study were almost the same as in the RCTs. However, to assess the true magnitude of the treatment effect, the design and actual implementation of the analysis must be critically evaluated.

Long-term and short-term outcomes after laparoscopic versus open surgery for advanced gastric cancer: An updated meta-analysis

BACKGROUND

The efficacy of laparoscopy for advanced gastric cancer (AGC) remains controversial.

MATERIALS AND METHODS

We conducted a literature search on the EMBASE, PubMed and Cochrane Library databases to identify relevant available articles published between the time of the databases' inception and July 2020.

RESULTS

A total of 14,689 patients were included in the 41 studies identified. A total of 6976 patients were in an laparoscopic approach group (LG) and 7713 patients were in an open approach group (OG). The meta-analysis showed that in randomized control trials (RCTs), LG were better than OG in terms of estimated blood loss, time to oral intake and time to first flatus while the operation time and proximal resection margin (PRM) were significantly worse in LG than in OG. In the non-RCTs, LG had shorter hospital stays, less blood loss, less intraoperative transfusion, less time to oral intake, time to first flatus, time to ambulation; less overall or serious complications; and better 3-year and 5-year overall or disease-free survival (DFS). Operation times and PRM were significantly worse for LGs.

CONCLUSION

The safety and effectiveness of laparoscopic surgery for AGC is not inferior to that of traditional open surgery, and to a certain extent, can reduce trauma, facilitate recovery, and be validated in RCTs and non-RCTs. In the real-world cohort, laparoscopic surgery for gastric cancer achieved a better survival rate and DFS rate. However, to evaluate the efficacy of these two methods more comprehensively, high-quality randomized controlled trials and longer follow-up times are still needed.

A good preoperative immune prognostic index is predictive of better long-term outcomes after laparoscopic gastrectomy compared with open gastrectomy for stage II gastric cancer in elderly patients

BACKGROUND

It remains inconclusive whether laparoscopic gastrectomy (LG) has better long-term outcomes when compared with open gastrectomy (OG) for elderly gastric cancer (EGC). We attempted to explore the influence of the immune prognostic index (IPI) on the prognosis of EGCs treated by LG or OG to identify a population among EGC who may benefit from LG.

METHODS

We included 1539 EGCs treated with radical gastrectomy from January 2007 to December 2016. Propensity score matching was applied at a ratio of 1:1 to compare the LG and OG groups. The IPI based on dNLR ≥ cut-off value (dNLR) and sLDH ≥ cut-off value (sLDH) was developed, characterizing two groups (IPI = 0, good, 0 factors; IPI = 1, poor, 1 or 2 factors).

RESULTS

Of the 528 EGCs (LG: 264 and OG: 264), 271 were in the IPI = 0 group, and 257 were in the IPI = 1 group. In the entire cohort, the IPI = 0 group was associated with good 5-year overall survival (OS) (p = 0.001) and progression-free survival (PFS) (p = 0.003) compared to the IPI = 1 group; no significant differences in 5-year OS and PFS between the LG and OG groups were observed. In the IPI = 1 cohort, there was no significant difference in OS or PFS between the LG and OG groups across all tumor stages. However, in the IPI = 0 cohort, LG was associated with longer OS (p = 0.015) and PFS (p = 0.018) than OG in stage II EGC, but not in stage I or III EGC. Multivariate analysis showed that IPI = 0 was an independent protective factor for stage II EGC receiving LG, but not for those receiving OG.

CONCLUSION

The IPI is related to the long-term prognosis of EGC. Compared with OG, LG may improve the 5-year survival rate of stage II EGC with a good IPI score. This hypothesis needs to be further confirmed by prospective studies.

A matched cohort study of the failure pattern after laparoscopic and open gastrectomy for locally advanced gastric cancer: does the operative approach matter?

BACKGROUND

Due to lacking evidence for confirming the efficacy of performing laparoscopic surgery for locally advanced gastric cancer (LAGC). Therefore, this study aimed to compare the static and dynamic failure patterns after laparoscopic gastrectomy (LG) and open gastrectomy (OG) in LAGC.

METHODS

A total of 1792 LAGC patients who underwent radical resection between January 2010 and January 2017 were divided into the LG group (n = 1557) and the OG group (n = 235). Propensity score matching was performed to balance the two groups. Dynamic hazard rates of failure were calculated using the hazard function. Early and late failure were defined as failure occurring before and after 2 years since surgery, respectively.

RESULTS

A total of 1175 patients with LAGC were included after matching (LG group, n = 940; OG, n = 235). The failure rate of the whole cohort was 43.2% (508/1175), accounting for 41.4% (389/940) and 50.6% (119/235) in the LG and OG groups, respectively. Although the two groups showed no significant differences in failure rate for any failure type, landmark analysis showed a lower early distant recurrence rate in the stage IIa-IIIb subgroup of the LG group (OG versus LG: 30.3% versus 21.1%, P = 0.004). The dynamic hazard rate peaked at 9.4 months (peak rate = 0.0186) before gradually declining. In stage IIa-IIIb patients, the hazard rate of the OG group remained significantly higher than that of the LG group within the first 2 years in terms of distant recurrence (peak rate: OG versus LG, 0.0091 versus 0.0055).

CONCLUSION

Given the differences in early failure between LG and OG, more intensive surveillance for distant recurrence within the first 2 years should be considered for patients with stage IIa-IIIb after OG.