Short-Term Outcomes Analysis Comparing Open, Laparoscopic, Laparoscopic-Assisted, and Robotic Distal Gastrectomy for Locally Advanced Gastric Cancer: A Randomized Trials Network Analysis.

BACKGROUND: Minimally invasive surgery for the treatment of locally advanced gastric cancer (AGC) is debated. The aim of this study was to execute a comprehensive assessment of principal surgical treatments for resectable distal gastric cancer. METHODS: Systematic review and randomized controlled trials (RCTs) network meta-analysis. Open (Op-DG), laparoscopic-assisted (LapAs-DG), totally laparoscopic (Lap-DG), and robotic distal gastrectomy (Rob-DG) were compared. Pooled effect-size measures were the risk ratio (RR), the weighted mean difference (WMD), and the 95% credible intervals (CrIs). RESULTS: Ten RCTs (3823 patients) were included. Overall, 1012 (26.5%) underwent Lap-DG, 902 (23.6%) LapAs-DG, 1768 (46.2%) Op-DG, and 141 (3.7%) Rob-DG. Anastomotic leak, severe complications (Clavien-Dindo > 3), and in-hospital mortality were comparable. No differences were observed for reoperation rate, pulmonary complications, postoperative bleeding requiring transfusion, surgical-site infection, cardiovascular complications, number of harvested lymph nodes, and tumor-free resection margins. Compared to Op-DG, Lap-DG and LapAs-DG showed a significantly reduced intraoperative blood loss with a trend toward shorter time to first flatus and reduced length of stay. CONCLUSIONS: LapAs-DG, Lap-DG, and Rob-DG performed in referral centers by dedicated surgeons have comparable short-term outcomes to Op-DG for locally AGC.

Does Thoracic Duct Ligation at the Time of Esophagectomy Impact Long-Term Survival? An Individual Patient Data Meta-Analysis.

Background: Thoracic duct ligation (TDL) during esophagectomy has been proposed to reduce the risk of postoperative chylothorax. Because of its role in immunoregulation, some authors argued that it had an unfavorable TDL effect on survival. The aim of this study was to analyze the effect of TDL on overall survival (OS). Methods: PubMed, MEDLINE, Scopus, and Web of Science were searched through December 2023. The primary outcome was 5-year OS. The restricted mean survival time difference (RMSTD), hazard ratios (HRs), and 95% confidence intervals (CI) were used as pooled effect size measures. The GRADE methodology was used to summarize the certainty of the evidence. Results: Five studies (3291 patients) were included. TDL was reported in 54% patients. The patients' age ranged from 49 to 69, 76% were males, and BMI ranged from 18 to 26. At the 5-year follow-up, the combined effect from the multivariate meta-analysis is -3.5 months (95% CI -6.1, -0.8) indicating that patients undergoing TDL lived 3.5 months less compared to those without TDL. TDL was associated with a significantly higher hazard for mortality at 12 months (HR 1.54, 95% CI 1.38-1.73), 24 months (HR 1.21, 95% CI 1.12-1.35), and 28 months (HR 1.14, 95% CI 1.02-1.28). TDL and noTDL seem comparable in terms of the postoperative risk for chylothorax (RR = 0.66; p = 0.35). Conclusions: In this study, concurrent TDL was associated with reduced 5-year OS after esophagectomy. This may suggest the need of a rigorous follow-up within the first two years of follow-up.

Long-Term Impact of Severe Postoperative Complications after Esophagectomy for Cancer: Individual Patient Data Meta-Analysis.

BACKGROUND: Severe postoperative complications (SPCs) may occur after curative esophagectomy for cancer and are associated with prolonged hospital stay, augmented costs, and increased in-hospital mortality. However, the effect of SPCs on survival after esophagectomy is uncertain. AIM: To assess the impact of severe postoperative complications (SPCs) on long-term survival following curative esophagectomy for cancer, we conducted a systematic search of PubMed, MEDLINE, Scopus, and Web of Science databases up to December 2023. The included studies examined the relationship between SPCs and survival outcomes, defining SPCs as Clavien-Dindo grade > 3. The primary outcome measure was long-term overall survival (OS). We used restricted mean survival time difference (RMSTD) and 95% confidence intervals (CIs) to calculate pooled effect sizes. Additionally, we applied the GRADE methodology to evaluate the certainty of the evidence. RESULTS: Ten studies (2181 patients) were included. SPCs were reported in 651 (29.8%) patients. The RMSTD overall survival analysis shows that at 60-month follow-up, patients experiencing SPCs lived for 8.6 months (95% Cis -12.5, -4.7; p < 0.001) less, on average, compared with no-SPC patients. No differences were found for 60-month follow-up disease-free survival (-4.6 months, 95% CIs -11.9, 1.9; p = 0.17) and cancer-specific survival (-6.8 months, 95% CIs -11.9, 1.7; p = 0.21). The GRADE certainty of this evidence ranged from low to very low. CONCLUSIONS: This study suggests a statistically significant detrimental effect of SPCs on OS in patients undergoing curative esophagectomy for cancer. Also, a clinical trend toward reduced CSS and DFS was perceived.

Effect of complete mesocolic excision (cme) on long-term survival after right colectomy for cancer: multivariate meta-analysis and restricted mean survival time estimation.

INTRODUCTION: Debate exists concerning the impact of complete mesocolic excision (CME) on long-term oncological outcomes. The aim of this review was to condense the updated literature and assess the effect of CME on long-term survival after right colectomy for cancer. METHODS: PubMed, MEDLINE, Scopus, and Web of Science were searched through July 2023. The included studies evaluated the effect of CME on survival. The primary outcome was long-term overall survival. Restricted mean survival time difference (RMSTD), hazard ratio (HR), and 95% confidence intervals (CI) were used as pooled effect size measures. GRADE methodology was used to summarize the certainty of evidence. RESULTS: Ten studies (3665 patients) were included. Overall, 1443 (39.4%) underwent CME. The RMSTD analysis shows that at 60-month follow-up, stage I-III CME patients lived 2.5 months (95% CI 1.1-4.1) more on average compared with noCME patients. Similarly, stage III patients that underwent CME lived longer compared to noCME patients at 55-month follow-up (6.1 months; 95% CI 3.4-8.5). The time-dependent HRs analysis for CME vs. noCME (stage I-III disease) shows a higher mortality hazard in patients with noCME at 6 months (HR 0.46, 95% CI 0.29-0.71), 12 months (HR 0.57, 95% CI 0.43-0.73), and 24 months (HR 0.73, 95% CI 0.57-0.92) up to 27 months. CONCLUSIONS: This study suggests that CME is associated with unclear OS benefit in stage I-III disease. Caution is recommended to avoid overestimation of the effect of CME in stage III disease since the marginal benefit of a more extended resection may have been influenced by tumor biology/molecular profile and multimodal adjuvant treatments.

Regional differences in outcomes with ablation versus drug therapy for atrial fibrillation: Results from the CABANA trial.

BACKGROUND: The finding of unexpected variations in treatment benefits by geographic region in international clinical trials raises complex questions about the interpretation and generalizability of trial findings. We observed such geographical variations in outcome and in the effectiveness of atrial fibrillation (AF) ablation versus drug therapy in the Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation (CABANA) trial. This paper describes these differences and investigates potential causes. METHODS: The examination of treatment effects by geographic region was a prespecified analysis. CABANA enrolled patients from 10 countries, with 1,285 patients at 85 North American (NA) sites and 919 at 41 non-NA sites. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Death and first atrial fibrillation recurrence were secondary endpoints. RESULTS: At least 1 primary endpoint event occurred in 157 patients (12.2%) from NA and 33 (3.6%) from non-NA sites over a median 54.9 and 40.5 months of follow-up, respectively (NA/non-NA adjusted hazard ratio (HR) 2.18, 95% confidence interval (CI) 1.48-3.21, P < .001). In NA patients, 78 events occurred in the ablation and 79 in the drug arm, (HR 0.91, 95% CI 0.66, 1.24) while 11 and 22 events occurred in non-NA patients (HR 0.51, 95% CI 0.25,1.05, interaction P = .154). Death occurred in 53 ablation and 51 drug therapy patients in the NA group (HR 0.96, 95% CI 0.65,1.42) and in 5 ablation and 16 drug therapy patients in the non-NA group (HR 0.32, 95% CI 0.12,0.86, interaction P = .044). Adjusting for baseline regional differences or prognostic risk variables did not account for the regional differences in treatment effects. Atrial fibrillation recurrence was reduced by ablation in both regions (NA: HR 0.54, 95% CI 0.46, 0.63; non-NA: HR 0.44, 95% CI 0.30, 0.64, interaction P = .322). CONCLUSIONS: In CABANA, primary outcome events occurred significantly more often in the NA group but assignment to ablation significantly reduced all-cause mortality in the non-NA group only. These differences were not explained by regional variations in procedure effectiveness, safety, or patient characteristics. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT0091150; https://clinicaltrials.gov/study/NCT00911508.

Long-Term Impact of D2 Lymphadenectomy during Gastrectomy for Cancer: Individual Patient Data Meta-Analysis and Restricted Mean Survival Time Estimation.

BACKGROUND: Debate exists concerning the impact of D2 vs. D1 lymphadenectomy on long-term oncological outcomes after gastrectomy for cancer. METHODS: PubMed, MEDLINE, Scopus, and Web of Science were searched and randomized controlled trials (RCTs) analyzing the effect of D2 vs. D1 on survival were included. Overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS) were assessed. Restricted mean survival time difference (RMSTD) and 95% confidence intervals (CI) were used as effect size measures. RESULTS: Five RCTs (1653 patients) were included. Overall, 805 (48.7%) underwent D2 lymphadenectomy. The RMSTD OS analysis shows that at 60-month follow-up, D2 patients lived 1.8 months (95% CI -4.2, 0.7; p = 0.14) longer on average compared to D1 patients. Similarly, 60-month CSS (1.2 months, 95% CI -3.9, 5.7; p = 0.72) and DFS (0.8 months, 95% CI -1.7, 3.4; p = 0.53) tended to be improved for D2 vs. D1 lymphadenectomy. CONCLUSIONS: Compared to D1, D2 lymphadenectomy is associated with a clinical trend toward improved OS, CSS, and DFS at 60-month follow-up.

Short-term Outcomes of Different Techniques for Gastric Ischemic Preconditioning Before Esophagectomy: A Network Meta-analysis.

BACKGROUND: Ischemia at the anastomotic site plays a critical role determinant in the development of anastomosis-related complications after esophagectomy. Gastric ischemic conditioning (GIC) before esophagectomy has been described to improve the vascular perfusion at the tip of the gastric conduit with a potential effect on anastomotic leak (AL) and stenosis (AS) risk minimization. Laparoscopic (LapGIC) and angioembolization (AngioGIC) techniques have been reported. PURPOSE: Compare short-term outcomes among different GIC techniques. MATERIALS AND METHODS: Systematic review and network meta-analysis. One-step esophagectomy (noGIC), LapGIC, and AngioGIC were compared. Primary outcomes were AL, AS, and gastric conduit necrosis (GCN). Risk ratio (RR) and weighted mean difference (WMD) were used as pooled effect size measures, whereas 95% credible intervals (CrIs) were used to assess relative inference. RESULTS: Overall, 1760 patients (14 studies) were included. Of those, 1028 patients (58.4%) underwent noGIC, 593 (33.6%) LapGIC, and 139 (8%) AngioGIC. AL was reduced for LapGIC versus noGIC (RR=0.68; 95% CrI 0.47-0.98) and AngioGIC versus noGIC (RR=0.52; 95% CrI 0.31-0.93). Similarly, AS was reduced for LapGIC versus noGIC (RR=0.32; 95% CrI 0.12-0.68) and AngioGIC versus noGIC (RR=1.30; 95% CrI 0.65-2.46). The indirect comparison, assessed with the network methodology, did not show any differences for LapGIC versus AngioGIC in terms of postoperative AL and AS risk. No differences were found for GCN, pulmonary complications, overall complications, hospital length of stay, and 30-day mortality among different treatments. CONCLUSIONS: Compared to noGIC, both LapGIC and AngioGIC before esophagectomy seem equivalent and associated with a reduced risk for postoperative AL and AS.

Liquid biopsy in non-small cell lung cancer: a meta-analysis of state-of-the-art and future perspectives.

Introduction: To date, tissue biopsy represents the gold standard for characterizing non-small-cell lung cancer (NSCLC), however, the complex architecture of the disease has introduced the need for new investigative approaches, such as liquid biopsy. Indeed, DNA analyzed in liquid biopsy is much more representative of tumour heterogeneity. Materials and methods: We performed a meta-analysis of 17 selected papers, to attest to the diagnostic performance of liquid biopsy in identifying EGFR mutations in NSCLC. Results: In the overall studies, we found a sensitivity of 0.59, specificity of 0.96 and diagnostic odds ratio of 24,69. Since we noticed a high heterogeneity among different papers, we also performed the meta-analysis in separate subsets of papers, divided by 1) stage of disease, 2) experimental design and 3) method of mutation detection. Liquid biopsy has the highest sensitivity/specificity in high-stage tumours, and prospective studies are more reliable than retrospective ones in terms of sensitivity and specificity, both NGS and PCR-based techniques can be used to detect tumour DNA in liquid biopsy. Discussion: Overall, liquid biopsy has the potential to help the management of NSCLC, but at present the non-homogeneous literature data, lack of optimal detection methods, together with relatively high costs make its applicability in routine diagnostics still challenging.

Pulmonary Lobectomy for Early-Stage Lung Cancer with Uniportal versus Three-Portal Video-Assisted Thoracic Surgery: Results from a Single-Centre Randomized Clinical Trial.

Video-assisted thoracic surgery (VATS) is a consolidated approach; however, there is no consensus on the number of ports leading to less postoperative pain. We compared early postoperative pain after uniportal and three-portal VATS lobectomy for early-stage NSCLC. In this randomized clinical trial, patients undergoing VATS lobectomy were randomly assigned to receive uniportal (U-VATS Group) or three-portal (T-VATS Group) VATS. The inclusion criteria were age ≤ 80 years and ASA < 4. The exclusion criteria were clinical T3, previous thoracic surgery, induction therapy, chest radiotherapy, connective tissue or vascular diseases, major organ failure, and analgesics or corticosteroids use. The postoperative analgesia protocol was based on NRS. Pain was measured as analgesic consumption; the secondary endpoints were intra- and postoperative complications, conversion rate, surgical time, dissected lymph nodes, hospital stay, and respiratory function. Out of 302 eligible patients, 120 were included; demographics were distributed homogeneously. The mean cumulative morphine consumption (CMC) in the U-VATS Group after 7 days was lower than in the T-VATS Group (77.4 mg vs. 90.1 mg, p = 0.003). Intraoperative variables and postoperative complications were comparable. The 30-day intercostal neuralgia rate was lower in the U-VATS Group, without reaching statistical significance. Patients undergoing U-VATS showed a lower analgesic consumption compared with the T-VATS Group; analgesic consumption was moderate in both groups.

Effect of gastric ischemic conditioning prior to esophagectomy: systematic review and meta-analysis.

Ischemia at the anastomotic site is thought to be a protagonist in the development of anastomosis-related complications while different strategies to overcome this problem have been reported. Gastric ischemic conditioning (GIC) prior to esophagectomy has been described with this intent. Evaluate the effect of GIC on anastomotic complications after esophagectomy. Scopus, Web of Science, MEDLINE, and PubMed were investigated up to March 31st, 2023. We considered articles that appraised short-term outcomes after GIC vs. no GIC in patients undergoing esophagectomy. Anastomotic leak (AL), anastomotic stricture (AS), and gastric conduit necrosis (GCN) were primary outcomes. Risk ratio (RR) and standardized mean difference (SMD) were used as pooled effect size measures, whereas 95% confidence intervals (95% CIs) were used to calculate related inference. Fourteen studies (1760 patients) were included. Of those, 732 (41.6%) underwent GIC, while 1028 (58.4%) underwent one-step esophagectomy. Compared with no GIC, GIC was related to a reduced RR for AL (R RR = 0.63; 95% CI 0.47-0.86; p < 0.01) and AS (RR = 0.51; 95% CI 0.29-0.91; p = 0.02), whereas no differences were found for GCN (RR = 0.56; 95% CI 0.19-1.61; p = 0.28). Postoperative pneumonia (RR = 1.09; p = 0.99), overall complications (RR = 0.87; p = 0.19), operative time (SMD - 0.58; p = 0.07), hospital stay (SMD 0.66; p = 0.09), and 30-day mortality (RR = 0.69; p = 0.22) were comparable. GIC prior to esophagectomy seems associated with a reduced risk for AL and AS. Further studies are necessary to identify the subset of patients who can benefit from this procedure, the optimal technique, and the timing of GIC prior to esophagectomy.

Short-term outcomes of different esophagojejunal anastomotic techniques during laparoscopic total gastrectomy: a network meta-analysis.

BACKGROUND: Different techniques have been described for esophagojejunostomy (EJ) during laparoscopic total gastrectomy (LTG) for gastric cancer. Linear stapled techniques include overlap (OL) and functional end-to-end anastomosis (FEEA) while single staple technique (SST), hemi-double staple technique (HDST), and OrVil® are circular stapled approaches. Nowadays, the choice among techniques for EJ depends on operating surgeon personal preference. PURPOSE: To compare short-term outcomes of different EJ techniques during LTG. METHODS: Systematic review and network meta-analysis. OL, FEEA, SST, HDST, and OrVil® were compared. Primary outcomes were anastomotic leak (AL) and stenosis (AS). Risk ratio (RR) and weighted mean difference (WMD) were used as pooled effect size measures, whereas 95% credible intervals (CrI) were used to measure relative inference. RESULTS: Overall, 3177 patients (20 studies) were included. The technique for EJ was SST (n = 1026; 32.9%), OL (n = 826; 26.5%), FEEA (n = 752; 24.1%), OrVil® (n = 317; 10.1%), and HDST (n = 196; 6.4%). AL was comparable for OL vs. FEEA (RR = 0.82; 95% CrI 0.47-1.49), OL vs. SST (RR = 0.55; 95% CrI 0.27-1.21), OL vs. OrVil® (RR = 0.54; 95% CrI 0.32-1.22), and OL vs. HDST (RR = 0.65; 95% CrI 0.28-1.63). Similarly, AS was similar for OL vs. FEEA (RR = 0.46; 95% CrI 0.18-1.28), OL vs. SST (RR = 0.89; 95% CrI 0.39-2.15), OL vs. OrVil® (RR = 0.36; 95% CrI 0.14-1.02), and OL vs. HDST (RR = 0.61; 95% CrI 0.31-1.21). Anastomotic bleeding, time to soft diet resumption, pulmonary complications, hospital length of stay, and mortality were comparable while operative time was reduced for FEEA. CONCLUSIONS: This network meta-analysis shows similar postoperative AL and AS risk when comparing OL, FEEA, SST, HDST, and OrVil® techniques. Similarly, no differences were found for anastomotic bleeding, operative time, soft diet resumption, pulmonary complications, hospital length of stay and 30-day mortality.

Effect of Anastomotic Leak on Long-Term Survival After Esophagectomy: Multivariate Meta-analysis and Restricted Mean Survival Times Examination.

BACKGROUND: Anastomotic leak (AL) is a serious complication after esophagectomy. It is associated with prolonged hospital stay, increased costs, and increased risk for 90-day mortality. Controversy exists concerning the impact of AL on survival. This study was designed to investigate the effect of AL on long-term survival after esophagectomy for esophageal cancer. METHODS: PubMed, MEDLINE, Scopus, and Web of Science were searched through October 30, 2022. The included studies evaluated the effect of AL on long-term survival. Primary outcome was long-term overall survival. Restricted mean survival time difference (RMSTD), hazard ratio (HR), and 95% confidence intervals (CI) were used as pooled effect size measures. RESULTS: Thirteen studies (7118 patients) were included. Overall, 727 (10.2%) patients experienced AL. The RMSTD analysis shows that at 12, 24, 36, 48, and 60 months, patients not experiencing AL live an average of 0.7 (95% CI 0.2-1.2; p < 0.001), 1.9 (95% CI 1.1-2.6; p < 0.001), 2.6 (95% CI 1.6-3.7; p < 0.001), 3.4 (95% CI 1.9-4.9; p < 0.001), and 4.2 (95% CI 2.1-6.4; p < 0.001) months longer compared with those with AL, respectively. The time-dependent HRs analysis for AL versus no AL shows a higher mortality hazard in patients with AL at 3 (HR 1.94, 95% CI 1.54-2.34), 6 (HR 1.56, 95% CI 1.39-1.75), 12 (HR 1.47, 95% CI 1.24-1.54), and 24 months (HR 1.19, 95% CI 1.02-1.31). CONCLUSIONS: This study seems to suggest a modest clinical impact of AL on long-term OS after esophagectomy. Patients who experience AL seem to have a higher mortality hazard during the first 2 years of follow-up.

Impact of postoperative NSAIDs administration on anastomotic leak after esophago-gastric surgery: systematic review and meta-analysis.

Anastomotic leak (AL) is a feared complication of esophago-gastric surgery. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used to treat postoperative pain. Previous analyses conveyed heterogeneous data for colorectal surgery with a tendency toward high risk for AL after NSAIDs administration. In the setting of upper gastrointestinal (GI) surgery data are even more puzzled. The purpose of the present study was to assess whether an association exists between postoperative NSAIDs administration and AL after esophago-gastric surgery. PubMed, MEDLINE, Scopus, and Web of Science were searched up to November 2022. The included studies evaluated outcomes for NSAIDs vs. no NSAIDs administration after esophago-gastric surgery. The primary outcome was anastomotic leak (AL). Risk ratio (RR) and 95% confidence intervals (95% CI) were used to assess pooled effect size and relative inference. Six studies (43,784 patients) were included. The patient age ranged from 31 to 84 years, 82.4% were males and preoperative BMI ranged from 15 to 31 kg/m2. Esophagectomy was performed in 95% of patients. NSAIDs were administered in 18,075 (41.3%) patients. The cumulative incidence of AL was similar for NSAIDs vs. no NSAIDs (13.6% vs. 13.4%). The risk for postoperative AL was similar for NSAIDs vs. no NSAIDs administration (RR 1.49; 95% CI 0.81-2.75; p = 0.19). The cumulative incidence of postoperative gastrointestinal bleeding (0.36% vs. 0.39%), acute kidney injury (0.62% vs. 0.71%), and in-hospital mortality (2.39% vs. 2.66%) were comparable. NSAIDs administration for postoperative analgesia seems not associated with an increased risk for AL after esophago-gastric surgery.

Oncological Outcomes of Segmentectomy versus Lobectomy in Clinical Stage I Non-Small Cell Lung Cancer up to Two Centimeters: Systematic Review and Meta-Analysis.

OBJECTIVE: In recent years, pulmonary segmentectomy has emerged as an alternative to lobectomy for the treatment of patients with clinical stage I non-small cell lung cancer. Considering the conflicting results reported in the literature, the oncological effectiveness of segmentectomy remains controversial. To provide new insight into oncological results, we reviewed the literature, including recent randomized trials. METHODS: We performed a systematic review for surgical treatment of stage I NSCLC up to 2 cm using MEDLINE and the Cochrane Database from 1990 to December 2022. Primary outcomes for pooled analysis were overall and disease-free survival; secondary outcomes were postoperative complications and 30-day mortality. RESULTS: Eleven studies were considered for the meta-analysis. The pooled analysis included 3074 and 2278 patients who received lobectomy and segmentectomy, respectively. The estimated pooled hazard ratio showed a similar hazard for segmentectomy compared to lobectomy in terms of overall and disease-free survival. The restricted mean survival time difference between the two procedures was statistically and clinically not significant for overall and disease-free survival. Nevertheless, the overall survival hazard ratio was time-dependent: segmentectomy was at a disadvantage starting from 40 months after surgery. Six papers reported 30-day mortality: there were no events on 1766 procedures. The overall relative risk showed that the postoperative complication rate was higher in segmentectomy compared to lobectomy, without statistical significance. CONCLUSIONS: Our results suggest that segmentectomy might be a useful alternative to lobectomy for stage I NSCLC up to 2 cm. However, this appears to be time-dependent; in fact, the risk ratio for overall mortality becomes unfavorable for segmentectomy starting at 40 months after surgery. This last observation, together with some still undefined questions (solid/non-solid ratio, depth of the lesion, modest functional savings, etc.), leave room for further investigations on the real oncological effectiveness of segmentectomy.

What is the ideal mesh location for incisional hernia prevention during elective laparotomy? A network meta-analysis of randomized trials.

BACKGROUND: Incisional hernia (IH) represents an important complication after surgery. Prophylactic mesh reinforcement (PMR) with different mesh locations [onlay (OL), retromuscular (RM), preperitoneal (PP), and intraperitoneal (IP)] has been described to possibly reduce the risk of postoperative IH. However, data reporting the 'ideal' mesh location are sparse. The aim of this study was to evaluate the optimal mesh location for IH prevention during elective laparotomy. METHODS: Systematic review and network meta-analysis of randomized controlled trials (RCTs). OL, RM, PP, IP, and no mesh (NM) were compared. The primary aim was postoperative IH. Risk ratio (RR) and weighted mean difference (WMD) were used as pooled effect size measures, whereas 95% credible intervals (CrI) were used to assess relative inference. RESULTS: Fourteen RCTs (2332 patients) were included. Overall, 1052 (45.1%) had no mesh (NM) while 1280 (54.9%) underwent PMR stratified in IP ( n =344 pts), PP ( n =52 pts), RM ( n =463 pts), and OL ( n =421 pts) placement. Follow-up ranged from 12 months to 67 months. RM (RR=0.34; 95% CrI: 0.10-0.81) and OL (RR=0.15; 95% CrI: 0.044-0.35) were associated with significantly reduced IH RR compared to NM. A tendency toward reduced IH RR was noticed for PP versus NM (RR=0.16; 95% CrI: 0.018-1.01), while no differences were found for IP versus NM (RR=0.59; 95% CrI: 0.19-1.81). Seroma, hematoma, surgical site infection, 90-day mortality, operative time and hospital length of stay were comparable among treatments. CONCLUSIONS: RM or OL mesh placement seems associated with reduced IH RR compared to NM. PP location appears promising; however, future studies are warranted to corroborate this preliminary indication.