The Impact of the Number of Ports on Perioperative Outcomes Following Video-Assisted Thoracoscopic Surgery for Non-Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Abstract

Video-assisted thoracoscopic surgery (VATS) has emerged as a less invasive technique for treating resected lung cancer compared with open surgery. In recent years, the uniportal VATS technique has gained popularity for lung resection in small nodules and ground glass lesions. However, it remains unclear whether single-port VATS offers more favorable perioperative outcomes than multi-port approaches. This study aims to evaluate the perioperative outcomes of single-port versus 2-port and 3-port VATS in patients with early-stage non-small cell lung cancer. A literature search was conducted across 5 online databases (PubMed, CENTRAL, ProQuest, SAGE, and ScienceDirect). Meta-analysis was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines. Study quality was assessed using the risk of bias tool in randomized trials (RoB 2) and the Newcastle-Ottawa Scale, while meta-analysis was conducted with Review Manager (RevMan) 5.4. This study was registered in PROSPERO under protocol number CRD42025634395. A comprehensive initial search identified 9,178 records, of which 22 studies were included in the systematic review and 19 were incorporated into the meta-analysis, with a total of 3,324 participants. Compared with 3-port VATS, single-port VATS was associated with significantly lower intra-operative blood loss (mean difference [MD], –10.52; 95% confidence interval [CI], –17.37 to –3.66; p=0.003), shorter chest tube duration (MD, –0.71; 95% CI, –1.07 to –0.35; p<0.001), lower postoperative drainage volume (MD, –68.25; 95% CI, –117.64 to –18.87; p=0.007), shorter postoperative hospital stay (MD, –1.00; 95% CI, –1.65 to –0.35; p=0.003), and lower pain scores on postoperative day 1 and day 3 (MD, –0.73; 95% CI, –1.19 to –0.28; p=0.002; MD, –0.59; 95% CI, –0.85 to –0.32; p<0.001), as well as a reduced rate of postoperative complications (MD, 0.83; 95% CI, 0.69 to 0.99; p=0.04). No significant differences were observed between single-port and 2-port or 3-port VATS regarding operation time and number of dissected lymph nodes. The risk of bias was low, and the overall certainty was moderate. Single-port VATS is safe and feasible, with short-term outcomes comparable to those of 2-port and 3-port approaches.

Introduction

Lung cancer remains the leading cause of cancer-related deaths worldwide and continues to have the highest mortality rate among pulmonary diseases. More than a quarter of all cancer fatalities are attributed to lung cancer [1]. Lung cancer is the most frequently diagnosed cancer in men and is the second leading cause of cancer-related deaths in women, with an estimated 2.09 million new cases globally in 2018 [2]. Lung cancer is classified into 2 main types: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), with NSCLC accounting for 85%–90% of all lung cancer cases. The available therapeutic modalities for lung cancer include surgical intervention, radiation therapy, chemotherapy, and targeted therapy, with surgery remaining the primary treatment for patients with early-stage NSCLC [3].

Video-assisted thoracoscopic surgery (VATS) is a minimally invasive procedure in which a small video camera is inserted through small incisions into the patient’s chest [4]. VATS lobectomy with systemic lymph node dissection has been recommended by the 2006 National Cancer Comprehensive Network guidelines as the standard surgical procedure for early-stage lung cancer. In its early adoption, the VATS technique faced criticism due to concerns about operative safety and outcomes compared with open thoracotomy. However, over the past 2 decades, studies have demonstrated that patients with early NSCLC derive greater benefits from VATS than from conventional thoracotomy, including reduced surgical trauma, shorter hospital stays, and a lower risk of postoperative complications [5].

Since the introduction of VATS as a surgical approach for lung cancer, surgeons have continually refined the technique to minimize surgical trauma [6]. The conventional approach most commonly employs the 3-port technique in thoracoscopic surgery. As surgical instruments and techniques have advanced, the number of incisions required for VATS has steadily decreased [7]. The development of single-port VATS, achieved by reducing the number of ports from 3 to 1, has become technically feasible [8]. Single-port VATS was initially reported in 2003 for treating uncomplicated pleura-related diseases, and in 2004, Rocco et al. [9] first described its use for wedge resection. In 2010, Gonzalez-Rivaz et al. [10] documented the first experience of single-port VATS lobectomy, marking the world’s first report of uniportal major lung resection. Since then, single-port VATS has been increasingly applied to various lung cancer resections, including pneumonectomy, segmentectomy, bronchial sleeve resection, and bronchoplasty [11,12].

The primary theoretical drawback of single-port VATS is the possibility of longer operation times, due to the small incision size, limited intercostal space (ICS), and the potential for interference between the thoracoscope and other instruments. The widespread use of single-port VATS in lung cancer surgery has prompted questions about its efficacy and safety compared to traditional multi-port procedures, necessitating a comprehensive review of the available literature [13]. A previous meta-analysis suggested that single-port VATS may provide superior perioperative outcomes compared with multi-port VATS [7]. However, to date, no study has separately compared 2-port and 3-port VATS with single-port VATS specifically in NSCLC patients. Moreover, no meta-analysis has compared perioperative outcomes between single-port, 2-port, and 3-port VATS anatomical resections for NSCLC based on different study designs. Therefore, this study aimed to evaluate the perioperative outcomes of single-port versus 2-port and 3-port VATS in early-stage NSCLC patients. Specifically, this study addressed the following question: In adults with early-stage NSCLC (Population), does single-port VATS (Intervention), compared with 2-port or 3-port VATS (Comparator), improve perioperative outcomes (Outcomes)?

Methods

No ethical approval was required because this review analyzed secondary data of literature. This systematic review and meta-analysis was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) 2020 guidelines and registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 6 January 2025 under registration number CRD42025634395. Although the literature search was completed on September 30, 2024, the registration was finalized slightly later due to administrative delays during the preparation phase. Importantly, registration was completed prior to data extraction and analysis. No changes were made to the predefined outcomes, inclusion criteria, or planned analyses after registration. Throughout the review process, we adhered strictly to the original protocol to ensure transparency and methodological integrity.

Search strategy

We searched for eligible studies evaluating the safety and feasibility of single-port versus 2-port and 3-port VATS anatomical resection for NSCLC from inception until 30 September 2024 in 5 online databases (PUBMED, CENTRAL, ProQuest, SAGE, and ScienceDirect). The search strategy used was as follows: ((“Non-small-cell Lung Cancer” OR “Lung Neoplasm” OR “Lung Cancer” OR “Pulmonary Cancer” OR “Pulmonary Neoplasm”) AND (“Video-assisted Thoracoscopic Surgery” OR “Video-assisted Surgery” OR “VATS” OR “Uniportal Thoracic Surgery” OR “Single-port Surgery” OR “Two-port Surgery” OR “Three-port Surgery” OR “Multiport Surgery” OR “Multiportal Surgery”)).

Study selection

Eligibility criteria for included studies were as follows: (1) randomized controlled trials (RCTs) or observational studies (cross-sectional, cohort, or case-control) evaluating perioperative outcomes of VATS anatomical resection for NSCLC; (2) studies investigating patients aged ≥18 years who underwent single-port versus 2-port and/or 3-port VATS for NSCLC; (3) no prior history of thoracic surgery; (4) no restrictions regarding gender, race, or ethnicity; and (5) studies providing quantitative results or at least 1 finding for the outcomes of interest (operation time, intraoperative blood loss, number of dissected lymph nodes, chest tube duration, postoperative drainage volume, postoperative hospital stay, postoperative pain [Visual Analog Scale, VAS] score, postoperative complications, morbidity, and conversion rate). Exclusion criteria included: (1) case reports, case series, commentaries, editorials, letters, review articles, or in vivo/in vitro studies; (2) insufficient data; (3) studies combining multiport (2-port and 3-port) groups; (4) tumor-node-metastasis stage IV prior to surgery; and (5) unclear methodology.

Data extraction

Two reviewers independently assessed the titles and abstracts of all retrieved studies to identify duplicates. Studies were excluded if their titles or abstracts did not align with the study objectives. Articles meeting the eligibility criteria underwent in-depth full-text review prior to inclusion. Discrepancies were resolved through discussion with a third reviewer. The following data were extracted: first author, year of publication, country of origin, study design, sample size, demographic characteristics (age, gender), histology, type of VATS approach (single-port, 2-port, or 3-port), measured outcomes, and study results.

Statistical analysis

Statistical analyses were performed using RevMan ver. 5.4 (Cochrane Collaboration). Mean differences (MDs) were calculated for continuous variables, and odds ratios (ORs) for dichotomous variables, with all effect measures reported with 95% confidence intervals (95% CIs). Heterogeneity among studies was assessed using the I² statistic, with values <25% considered minimal, 25%–50% low, 50%–75% moderate, and >75% high heterogeneity. An I²<50% or a p-value >0.1 indicated no substantial heterogeneity and warranted the use of fixed effects models; otherwise, random effects models were used. Where heterogeneity was present, sensitivity analyses were conducted to investigate possible causes. A p-value <0.05 was considered statistically significant. Data were presented using forest plots. When ≥10 studies were included, funnel plots were generated to assess potential publication bias.

Quality assessment

Study quality was independently assessed by 2 reviewers using the Cochrane risk of bias 2 (RoB 2) tool for RCTs and the Newcastle-Ottawa Scale (NOS) for cohort studies. Inter-rater agreement was measured using the Cohen kappa statistic. Disagreements were resolved through discussion with a third reviewer. The RoB 2 tool evaluates 5 domains: (1) bias in the randomization process, (2) deviations from intended interventions, (3) missing outcome data, (4) measurement of outcomes, and (5) selection bias. An overall low risk of bias required low risk in all domains, while concerns in multiple domains or high risk in any domain resulted in an overall high risk of bias. The NOS assesses 3 domains: (1) participant selection, (2) comparability of study groups, and (3) outcome measurement. Studies with ≥7 NOS stars were considered high quality, those with at least 5 as fair, and all others as low quality. Risk of bias plots were created using “robvis” software. To evaluate publication bias in pooled analyses, Egger’s linear regression test was performed, complemented by Begg’s rank correlation test. A p-value >0.05 in both tests indicated no statistically significant evidence of publication bias.

Certainty of evidence

The certainty of evidence for each outcome was assessed using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach, considering domains such as risk of bias, inconsistency, indirectness, imprecision, and publication bias. Risk of bias was evaluated using the Cochrane RoB 2 tool for RCTs and the NOS for cohort studies. Imprecision was judged when confidence intervals were wide or sample sizes were small, and inconsistency was indicated by substantial heterogeneity (I²>50%). Outcomes were rated as high, moderate, low, or very low certainty. High certainty indicates strong confidence that the true effect is close to the estimated effect, whereas very low certainty suggests the true effect may differ substantially from the estimate. Two reviewers independently determined GRADE assessments, with disagreements resolved by discussion with a third reviewer.

Results

Study selection

The literature search process and results obtained were summarized in a flowchart (Fig. 1). The search strategy identified a total of 9,178 relevant studies (Appendix 1). After removal of duplicates and initial screening of titles and abstracts, 97 studies were assessed for eligibility. Of these, 74 studies did not meet the inclusion criteria (Appendix 2): 23 studies combined 2-port and 3-port populations, 47 did not focus on NSCLC, and 4 were review articles. Ultimately, 22 studies were included in the qualitative synthesis, with 19 studies providing sufficient data for inclusion in the meta-analysis. Two studies were excluded due to insufficient quantitative data regarding the outcomes of interest.

Fig. 1.

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) 2020 flow diagram of included studies. NSCLC, non-small cell lung cancer.

Characteristics of the included studies

A total of 3,324 patients from 16 cohort studies and 3 RCTs were included in the meta-analysis (Appendix 3). The majority of included studies were conducted in China, with sample sizes ranging from 52 to 439 participants (Table 1) [4-6,14-32]. Among the 22 studies, the lowest reported mean age was 54.4±7.4 years (3-port group, Rao et al. [24]), and the highest was 68.8±8.7 years (Tosi et al. [31]). Lobectomy was the most commonly performed surgical procedure. Ten studies utilized population matching based on baseline characteristics at study entry. Detailed characteristics are presented in Table 1 [4-6,14-32].

Table 1.

Characteristics of included studies

No.	Author (year)	Country of origin	Study type	Sample size				Mean age (yr)				Gender (male/female)			Surgery	TNM stage	Outcome of interesta)
				1-port	2-port	3-port		1-port	2-port	3-port		1-port	2-port	3-port
1.	Li et al. [14] (2013)	China	Cohort	87	NA	75		63.86±12.10	NA	66.20±8.72		65/22	NA	52/23	Lobectomy	T1-3N0-2M0	1, 2, 3, 4, 5, 6, 10
2.	Mu et al. [15] (2015)	China	Cohort	47	NA	47		56.67±11.62	NA	60.77±11.04		25/22	NA	14/33	Lobectomy, segmentectomy, wedge resection	T1-3N0-2M0	1, 2, 3, 4, 6, 10, 12
3.	Shen et al. [16] (2015)	China	Cohort	100	NA	100		61.5±7.9	NA	60.9±7.8		56/55	NA	55/45	Lobectomy	T1-3N0M0	1, 2, 3, 7, 11, 12, 14
4.	Zhu et al. [17] (2015)	China	Cohort	33	NA	49		62 (25–79)	NA	59 (31–81)		11/22	NA	19/30	Lobectomy	T1-2N0-2M0	1, 2, 3, 4, 6, 8, 10
5.	Dai et al. [18] (2016)	China	Cohort	63	63	NA		58.68±9.24	57.11±12.22	NA		40/23	46/17	NA	Lobectomy	T1-3N0-2M0	1, 2, 3, 4, 7, 8, 9, 10, 13
6.	Han et al. [4] (2017)	Korea	Cohort	203	68	168		62.9 (33–84)	63.2 (44–86)	64.1 (40–86)		132/71	41/27	105/63	Lobectomy, segmentectomy, sleeve resection, pneumonectomy, wedge resection	T1-2N0M0	1, 3, 4, 10, 11, 12
7.	Ke et al. [19] (2017)	China	Cohort	40	NA	40		63.2±12.1	NA	61.5±10.4		7/23	NA	8/22	Lobectomy	T1a-cN0M0	1, 2, 3, 4, 5, 6, 10
8.	Song et al. [20] (2017)	Korea	Cohort	26	NA	26		64.8±9.7	NA	65.0±9.4		15/11	NA	15/11	Lobectomy	T1-4N0-2M0	1, 2, 3, 4, 6, 10, 12
9.	Yan et al. [21] (2017)	China	Cohort	NA	279	152		NA	61.45±6.17	61.05±5.56		NA	163/116	81/71	NA	T1-2N0-1M0	1, 2, 3, 5, 6, 8, 9
10.	Liu et al. [22] (2018)	China	Cohort	166	162	NA		63.4 (22–84)	62.5 (45–82)	NA		89/88	88/74	NA	Lobectomy	T1a-cN0-1M0	1, 2, 4, 6, 10, 14
11.	Wang et al. [23] (2018)	China	Cohort	153	NA	113		61.52±9.70	NA	62.27±10.08		82/71	NA	69/44	Lobectomy	T1-2N0-1M0	1, 2, 3, 4, 5, 6, 8, 9, 10
12.	Rao et al. [24] (2019)	China	Cohort	153	NA	102		56.1±8.5	NA	54.4±7.4		67/43	NA	86/59	Lobectomy, pneumonectomy	NA	1, 2, 3, 4, 6, 9, 10
13.	Ye et al. [25] (2019)	China	RCT	74	NA	82		62.67±9.16	NA	61.83±8.26		43/31	NA	59/23	Lobectomy	T1-2N0-1M0	1, 2, 3, 4, 5, 7, 8, 9
14.	Zhao et al. [26] (2019)	China	Cohort	73	NA	56		67.5±4.6	NA	67.3±5.3		59/14	NA	47/9	Lobectomy	T1-2N0M0	1, 2, 4, 7, 8, 9, 10
15.	Tian et al. [27] (2020)	China	Cohort	38	43	30		58.34±7.32	59.56±7.72	60.17±6.56		17/21	21/22	17/13	Segmentectomy	T1a-cN0M0	1,2,3,4,5,6, 10,12
16.	Xie et al. [28] (2020)	China	Cohort	454	NA	454		58.0 (50–64)	NA	58.0 (50–64)		174/280	NA	178/276	Segmentectomy	T1a-cN0M0	1, 2, 3, 4, 10
17.	Xu et al. [29] (2020)	China	Cohort	60	NA	60		61.35±10.76	NA	63.50±9.64		33/27	NA	31/29	Lobectomy	NA	1, 2, 3, 4, 6, 10
18.	Yao et al. [30] (2020)	China	RCT	35	NA	34		58.23±9.76	NA	58.71±7.49		16/19	NA	16/18	Lobectomy	T1-2N0-1M0	1, 2, 3, 4, 7, 10, 12, 14
19.	Li et al. [6] (2021)	China	Cohort	80	NA	66		61.28±8.09	NA	62.00±11.33		41/39	NA	38/28	Lobectomy	T1-3N0-1M0	1, 2, 3, 4, 5, 6, 8, 9
20.	Sun et al. [5] (2022)	China	Cohort	143	NA	143		54.6 (11.9)	NA	54.8 (13.7)		29/114	NA	30/113	Segmentectomy	T1N0M0	1, 2, 3, 4, 6, 10, 12, 14
21.	Tosi et al. [31] (2023)	Italy	RCT	60	NA	60		66.7±11.3	NA	68.8±8.7		31/29	NA	30/30	Lobectomy	T1-2N0-1M0	1, 3, 4, 7, 8, 9
22.	Mi et al. [32] (2024)	China	Cohort	57	NA	57		78 (76–79)	NA	78 (76–79)		32/25	NA	35/22	Lobectomy, segmentectomy, wedge resection	T1-3N0-2M0	1, 2, 3, 4, 5, 6

Values are presented as number, mean±standard deviation, or median (interquartile range), unless otherwise stated.

TNM, tumor-node-metastasis; NA, not available/applicable; RCT, randomized controlled trial; POD, postoperative day.

^a)1: operation time; 2: intraoperative blood loss; 3: number of dissected lymph nodes; 4: chest tube duration; 5: drainage volume; 6: postoperative hospital stay; 7: total hospital stay; 8: pain score POD-1; 9: pain score POD-3; 10: postoperative complication; 11: morbidity; 12: conversion rate; 13: satisfaction score; 14: mortalities

Risk of bias

All cohort studies assessed using the NOS were determined to have a low risk of bias. Among the 3 RCTs evaluated with the RoB-2 tool, 2 showed some concerns for risk of bias, while 1 demonstrated low risk of bias. Inter-rater agreement for the risk-of-bias assessment was substantial (κ=0.78), indicating strong consistency between the 2 reviewers. Supplementary Tables 1 and 2 present the risk of bias assessment using RoB-2 and NOS tools. Fig. 2 displays (A) a traffic light plot and (B) a summary plot of the quality assessment for the included RCTs.

Fig. 2.

(A) Traffic light plot and (B) summary plot of the quality assessment of the included randomized controlled trials.

Publication bias

For outcomes with at least 10 included studies, funnel plots were generated to assess publication bias. This applied to operation time, intraoperative blood loss, number of dissected lymph nodes, and chest tube duration when comparing single-port versus 3-port groups. The funnel plots were visually symmetrical, indicating a low risk of publication bias (Appendix 4, Supplementary Figs. 1–4). This observation was further corroborated by non-significant p-values in both the Egger and Begg tests (p>0.05).

Certainty of evidence

The certainty of evidence was evaluated using the GRADE approach (Appendix 5) and ranged from moderate to high. High certainty of evidence was assigned for operation time (single-port versus 2-port), intraoperative blood loss (2-port versus 3-port), number of dissected lymph nodes, chest tube duration (single-port versus 2-port), and postoperative complications (single-port versus 3-port). Moderate certainty was assigned for operation time (single-port versus 3-port and 2-port versus 3-port), intraoperative blood loss (single-port versus 2-port and single-port versus 3-port), chest tube duration (single-port versus 3-port and 2-port versus 3-port), postoperative drainage volume, postoperative hospital stay, VAS score on postoperative day (POD) 1 and POD 3, morbidity, and conversion rate. The primary factors contributing to moderate certainty were significant heterogeneity (I²>50%) and small sample sizes. Overall, the certainty of evidence for most outcomes was rated as moderate.

Meta-analysis results

Operation time

Nineteen studies involving a total of 3,874 subjects reported data on operation time for VATS in NSCLC treatment. Of these, 3 studies compared single-port with 2-port, 17 compared single-port with 3-port, and 3 compared 2-port with 3-port; 2 studies compared single-port with both 2-port and 3-port groups. The forest plot demonstrated no significant differences among single-port, 2-port, and 3-port approaches regarding operation time (single-port versus 2-port: MD, 10.39; 95% CI, 0.22–20.56; p=0.05; single-port versus 3-port: MD, –3.23; 95% CI, –9.49 to 3.03; p=0.31; 2-port versus 3-port: MD, –7.50; 95% CI, –22.39 to 7.40; p=0.32) (Fig. 3). Heterogeneity was minimal in the single-port versus 2-port group (I²=0%), while moderate heterogeneity was found in the single-port versus 3-port (I²=74%) and 2-port versus 3-port (I²=65%) comparisons.

Fig. 3.

Forest plot for operation time in single-port vs. 2-port (A), single-port vs. 3-port (B), and 2-port vs. 3-port (C) video-assisted thoracoscopic surgery using a fixed-, random-, and fixed-effects model, respectively. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom; RCT, randomized controlled trial.

Intraoperative blood loss

Seventeen studies comprising 2,590 subjects provided data on intraoperative blood loss following VATS for NSCLC. Among these, 2 studies compared single-port with 2-port, 14 compared single-port with 3-port, and 2 compared 2-port with 3-port; 1 study compared single-port with both 2-port and 3-port. The forest plot indicated that single-port VATS was associated with significantly lower intraoperative blood loss compared to 3-port VATS (MD, –10.52; 95% CI, –17.37 to –3.66; p=0.003). Conversely, 3-port VATS resulted in significantly less blood loss than 2-port VATS (MD, 7.19; 95% CI, 2.77 to 11.60; p=0.001). No significant difference was observed between single-port and 2-port approaches (MD, –45.49; 95% CI, –117.90 to 26.92; p=0.22) (Fig. 4). Heterogeneity was minimal in the 2-port versus 3-port comparison (I²=0%), but moderate in single-port versus 2-port and single-port versus 3-port comparisons (I²=70% and 75%, respectively).

Fig. 4.

Forest plot for intraoperative blood loss in single-port vs. 2-port (A), single-port vs. 3-port (B), and 2-port vs. 3-port (C) video-assisted thoracoscopic surgery using a fixed-effects model. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom; RCT, randomized controlled trial.

Number of dissected lymph nodes

Eighteen studies, totaling 3,745 subjects, reported the number of dissected lymph nodes following VATS for NSCLC. Three studies compared single-port with 2-port, 16 compared single-port with 3-port, and 3 compared 2-port with 3-port; 2 studies compared single-port with both 2-port and 3-port. The forest plot suggested no significant differences among single-port, 2-port, and 3-port groups for the number of dissected lymph nodes (single-port versus 2-port: MD, –0.42; 95% CI, –1.45 to 0.62; p=0.43; single-port versus 3-port: MD, –0.02; 95% CI, –0.22 to 0.19; p=0.88; 2-port versus 3-port: MD, 0.01; 95% CI, –0.17 to 0.19; p=0.90) (Fig. 5). Heterogeneity was minimal across all groups (I²=0%).

Fig. 5.

Forest plot for number of dissected lymph nodes in single-port vs. 2-port (A), single-port vs. 3-port (B), and 2-port vs. 3-port (C) video-assisted thoracoscopic surgery using a fixed-effects model. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom; RCT, randomized controlled trial.

Chest tube duration

Sixteen studies involving 2,973 subjects reported on chest tube duration following VATS for NSCLC. Among these, 3 studies compared single-port with 2-port, 15 compared single-port with 3-port, and 2 compared 2-port with 3-port; 2 studies compared single-port with both 2-port and 3-port. The forest plot indicated that single-port VATS was associated with shorter chest tube duration compared to 3-port VATS (MD, –0.71; 95% CI, –1.07 to –0.35; p<0.001). No significant differences were observed between single-port and 2-port (MD, –0.25; 95% CI, –0.64 to 0.13; p=0.19), or between 2-port and 3-port approaches (MD, –0.44; 95% CI, –1.75 to 0.88; p=0.51) (Fig. 6). Heterogeneity was minimal in the single-port versus 2-port comparison (I²=0%), but high in the single-port versus 3-port (I²=80%) and 2-port versus 3-port (I²=91%) comparisons.

Fig. 6.

Forest plot for chest tube duration in single-port vs. 2-port (A), single-port vs. 3-port (B), and 2-port vs. 3-port (C) video-assisted thoracoscopic surgery using a fixed-effects model. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom; RCT, randomized controlled trial.

Drainage volume

Five studies, including a total of 1,146 subjects, reported data on drainage volume following VATS for NSCLC. Of these, 4 studies compared single-port with 3-port approaches, and 2 studies compared 2-port with 3-port approaches. Due to insufficient data, meta-analysis comparing single-port with 2-port could not be performed. The forest plot indicated that single-port VATS resulted in a lower drainage volume compared with 3-port VATS (MD, –68.25; 95% CI, –117.64 to –18.87; p=0.007). No significant difference was observed between 2-port and 3-port groups (MD, –40.92; 95% CI, –123.61 to 41.77; p=0.33) (Fig. 7). Moderate heterogeneity was found in the single-port versus 3-port comparison (I²=59%), while high heterogeneity was observed in the 2-port versus 3-port comparison (I²=90%).

Fig. 7.

Forest plot for postoperative drainage volume in single-port vs. 3-port (A) and 2-port vs. 3-port (B) video-assisted thoracoscopic surgery using a random-effects model. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom.

Postoperative hospital stay

Eleven studies with a combined total of 1,774 subjects reported on postoperative hospital stay following VATS for NSCLC. Among these, 10 studies compared single-port with 3-port, and 2 studies compared 2-port with 3-port. Meta-analysis comparing single-port with 2-port could not be performed due to insufficient data. The forest plot demonstrated that single-port VATS resulted in a shorter postoperative hospital stay compared with 3-port VATS (MD, –1.00; 95% CI, –1.65 to –0.35; p=0.003). No significant difference was observed between 2-port and 3-port groups (MD, –0.57; 95% CI, –2.17 to 1.04; p=0.49). High heterogeneity was present in both groups (single-port versus 3-port I²=80%; 2-port versus 3-port I²=96%) (Fig. 8).

Fig. 8.

Forest plot for postoperative hospital stay in single-port vs. 3-port (A) and 2-port vs. 3-port (B) video-assisted thoracoscopic surgery using a random-effects model. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom.

Pain score on POD 1 and POD 3

Seven studies comprising 979 subjects reported pain scores on postoperative day 1, while 6 studies including 621 subjects reported pain scores on postoperative day 3 following VATS for NSCLC. Pain was evaluated using the VAS. Both subgroups compared single-port with 3-port. Meta-analysis for single-port versus 2-port and 2-port versus 3-port subgroups could not be performed due to limited data, as only 1 study evaluated these comparisons for VAS score. The forest plot showed that single-port VATS was associated with lower VAS pain scores compared with 3-port VATS on both POD-1 and POD-3 (MD, –0.73; 95% CI, –1.19 to –0.28; p=0.002; MD, –0.59; 95% CI, –0.85 to –0.32; p<0.001, respectively) (Fig. 9). High heterogeneity was observed in both groups (I²=93% and 83%, respectively).

Fig. 9.

Forest plot in single-port vs. 3-port video-assisted thoracoscopic surgery for Visual Analog Scale score postoperative day (POD)-1 (A) and POD-3 (B) using a random-effects model. SD, standard deviation; IV, inverse variance; CI, confidence interval; df, degrees of freedom; RCT, randomized controlled trial.

Postoperative complications

Ten studies with a total of 1,292 subjects provided data on postoperative complications following single-port versus 3-port VATS for NSCLC. Meta-analysis could not be performed for single-port versus 2-port and 2-port versus 3-port subgroups due to limited data. The forest plot indicated that single-port VATS was associated with fewer postoperative complications compared with 3-port VATS (MD, 0.83; 95% CI, 0.69 to 0.99; p=0.04), with minimal heterogeneity (I²=0%) (Supplementary Fig. 5).

Morbidity

Two studies comprising 571 subjects provided information on morbidity following single-port versus 3-port VATS for NSCLC. Meta-analysis for single-port versus 2-port and 2-port versus 3-port subgroups could not be performed due to limited data. The forest plot suggested no significant difference between single-port and 3-port approaches regarding morbidity (MD, 0.55; 95% CI, 0.29 to 1.02; p=0.06), with minimal heterogeneity noted (I²=0%) (Supplementary Fig. 6).

Conversion rate

Five studies, including 1,328 subjects, provided data on conversion rate following VATS in NSCLC. Among them, 5 studies compared single-port with 2-port, and 2 studies compared 2-port with 3-port; 2 studies compared both single-port with 2-port and 2-port with 3-port. No significant difference was found in either group (MD, 0.76; 95% CI, 0.39 to 1.49; p=0.42; MD, 0.73; 95% CI, 0.25 to 2.15; p=0.57, respectively). Minimal heterogeneity was observed in both comparisons (I²=0% and 0%, respectively) (Supplementary Figs. 7, 8).

Discussion

The present study demonstrated that single-port VATS results in improved perioperative outcomes compared with 3-port VATS, including lower intraoperative blood loss, shorter chest tube duration, reduced postoperative drainage volume, shorter postoperative hospital stay, lower pain scores on POD 1 and POD 3, as well as a reduced incidence of postoperative complications. These findings are consistent with major results from previous studies [33,34]. There were no significant differences between single-port versus 2-port and 3-port VATS in terms of operation time and the number of dissected lymph nodes. Morbidity and conversion rates were also similar between the single-port and 3-port groups. Additionally, no significant differences were observed between single-port and 2-port groups regarding chest tube duration and intraoperative blood loss. Overall, these results indicate that single-port VATS can provide perioperative outcomes that are comparable to, or better than, those of 2-port and 3-port VATS [34].

Single-port VATS is performed through a single 3 to 5 cm incision at the 4th or 5th ICS along the anterior axillary line, eliminating the need for both the observation and vice-operation ports that are utilized in 3-port VATS [25]. In the multi-port approach, the observation port is typically placed at the 7th ICS along the posterior axillary line, where the chest wall muscles are thicker and the ICS is narrower, increasing the risk of injury to blood vessels and nerves. Reducing the number of incisions decreases tissue trauma to intercostal muscles and nerves.

A specific advantage of single-port VATS is the operative view [30,35,36]. The perspective provided by single-port VATS closely resembles that of thoracotomy, as the camera and instruments are introduced through the same incision, creating a surgical field similar to open surgery. Inserting the thoracoscope and instruments through a single port enables a more directed view of the target tissue. This approach can facilitate assessment of surgical distance, enhance precision, and minimize accidental injury during surgery, thereby reducing intraoperative blood loss and postoperative chest tube drainage [29,37]. In our study, single-port VATS was superior to 3-port VATS with respect to intraoperative blood loss and postoperative drainage volume, consistent with previous studies [7,12,18,30,38,39]. We also found that single-port VATS was associated with shorter chest tube duration, a reduced postoperative hospital stay, and a lower complication rate, further indicating its benefit for patient recovery.

Theoretically, reducing the number of incisions may increase the technical complexity of the procedure. The principal challenge in single-port VATS is the increased likelihood of instrument interference and crowding within the single incision. As a result, single-port VATS may be perceived as requiring a longer operation time [17]. However, our meta-analysis revealed that single-port VATS was not associated with a longer duration of surgery. We propose that surgeons performing single-port thoracoscopic procedures are typically more experienced with VATS in general, which may compensate for the technical difficulties of the single-port approach.

Postoperative pain is closely related to short-term quality of life in lung cancer patients. Poorly controlled acute postoperative pain can lead to chronic pain and may delay recovery of respiratory function, which negatively impacts long-term quality of life [40]. Our findings indicate that single-port VATS is associated with significantly lower pain scores on POD 1 and POD 3 compared with 3-port VATS. This is likely attributable to the use of a single utility port, where both the thoracoscope and instruments are introduced through 1 incision, thereby minimizing trauma and reducing the risk of injury to blood vessels and intercostal nerves, and resulting in less postoperative pain.

Mediastinal lymph node dissection is a key determinant of the effectiveness of radical lung cancer surgery, as it ensures accurate postoperative staging and influences prognosis [29,32]. Complete hilar and mediastinal lymph node dissection can reveal occult metastases, thereby guiding appropriate further treatment for patients [41]. Our results align with previous studies by Liu et al. [42], Chang et al. [43], and Shen et al. [16], which reported that the total number of dissected lymph nodes did not differ significantly between single-port and multi-port VATS. These findings suggest that single-port VATS achieves equivalent lymph node dissection as other techniques.

Despite these advantages, single-port VATS can be technically demanding. Reducing the number of ports requires the surgeon to operate within a less familiar surgical field compared to multi-port VATS [31]. Surgeons who are less experienced with multi-port VATS may encounter significant challenges, including potentially catastrophic intraoperative events such as bleeding, which may necessitate conversion to open thoracotomy. In our meta-analysis, however, no significant differences were observed between single-port and 3-port VATS regarding conversion rate or morbidity. Reported conversion rates from VATS to thoracotomy range from 0% to 23%, often due to bleeding or severe pleural adhesions [16,44,45]. Successful performance of single-port VATS therefore demands advanced surgical skills, a thorough understanding of pulmonary anatomy, and extensive experience in thoracoscopic surgery.

Our study has several limitations. Most of the included studies were retrospective, introducing potential selection and observer bias in the choice of surgical approach, which may weaken the overall strength of the results. Nonetheless, eleven studies did use propensity-matched analyses to improve patient matching. Notable heterogeneity was present among included studies, particularly in surgical technique, variations in learning curve for single-port and multi-port VATS, and differences in surgeon experience, all of which may influence patient outcomes. Moreover, due to the limited number of studies, we were unable to conduct subgroup analyses comparing specific port combinations (single-port versus 2-port versus 3-port) for certain outcomes. Additionally, although comprehensive search strategies were employed, most studies included were single-center retrospective studies from East Asia, limiting the generalizability of the findings. As such, the results should be interpreted with caution, and broad clinical recommendations should be avoided. Finally, our study did not include data on long-term oncologic outcomes such as cancer recurrence or survival rate. To confirm these findings, future large-scale prospective studies from diverse regions with longer follow-up and a focus on long-term oncologic outcomes—including recurrence and survival—are warranted to provide more robust and definitive evidence.

Conclusion

In summary, single-port VATS offers favorable perioperative results and therapeutic outcomes comparable to those of multi-port VATS. By minimizing the surgical incision, single-port VATS further reduces surgical trauma and accelerates postoperative recovery. These findings suggest that single-port VATS is a safe and feasible option for appropriately selected lung cancer patients and should be considered for its advantages in minimizing invasiveness.

Supplementary materials

Supplementary materials can be found via https://doi.org/10.5090/jcs.25.037. Supplementary Table 1. Newcastle-Ottawa Scale risk of bias for included cohorts. Supplementary Table 2. Cochrane risk of bias (RoB-2) for included RCTs. Supplementary Fig. 1. Funnel plot for operation time in single-port versus 3-port. Supplementary Fig. 2. Funnel plot for intraoperative blood loss in single-port versus 3-port. Supplementary Fig. 3. Funnel plot for number of dissected lymph nodes in single-port versus 3-port. Supplementary Fig. 4. Funnel plot for chest tube duration in single-port versus 3-port. Supplementary Fig. 5. Forest plot for postoperative complications in single-port versus 3-port. Supplementary Fig. 6. Forest plot for morbidity in single-port versus 3-port. Supplementary Fig. 7. Forest plot for conversion rate in single-port versus 3-port. Supplementary Fig. 8. Forest plot for conversion rate in 2-port versus 3-port.