Pulmonary function changes after thoracoscopic lobectomy versus intentional thoracoscopic segmentectomy for early-stage non-small cell lung cancer

Pulmonary Function Recovery and Displacement Patterns After Anatomic Segmentectomy vs Lobectomy

BACKGROUND

The functional benefit of segmentectomy compared with lobectomy remains controversial. This ambispective study characterizes the changes in pulmonary function as correlated to displacement patterns of residual lung after segmentectomies vs lobectomies.

METHODS

Patients with normal preoperative pulmonary function and undergoing segmentectomy or lobectomy between 2017 and 2021 were considered. Pulmonary function testing was scheduled preoperatively and at least 3 months postoperatively. Differences in the proportions of the median forced expiratory volume in 1 second (FEV1) reduction between segmentectomy and lobectomy were calculated. Covariance analysis was used to estimate the adjusted postoperative FEV1 (apoFEV1) and compare the difference value (DV) in apoFEV1 between segmentectomy and lobectomy.

RESULTS

The study enrolled 634 patients (334 lobectomies and 300 segmentectomies). Median difference in the proportions of the FEV1 reduction between segmentectomy and lobectomy was 4.58%, with maximal difference observed in right S6 (9.08%) and minimal difference in left S1+2+3 (2.80%). For resections involving the upper lobe, apoFEV1 was significantly higher after segmentectomy than after lobectomy (DV, 0.15-0.22 L), except for left S3 and S1+2+3 segmentectomies (DV, 0.08 L and 0.06 L, respectively). Compared with a lower lobe lobectomy, S6 segmentectomy conferred a higher apoFEV1, whereas S7+8 and S9+10 had a similar apoFEV1 (DV, 0.16-0.18 L, 0.07 L, and 0.00-0.06 L, respectively). Functional recovery after segmentectomy was associated with the number of intersegment planes (P < .01) and the presence of an adjacent nonoperated on lobe (P = .03).

CONCLUSIONS

Basilar and left S3 segmentectomies did not preserve more pulmonary function compared with their corresponding lobectomies, possibly due to the presence of multiple intersegmental resection planes.

Sublobar resection for small-sized non-small cell lung cancer: A comprehensive comparison between subsegmentectomy, segmentectomy and wedge resection

OBJECTIVES

Subsegmentectomy has been adopted for non-small cell lung cancer (NSCLC) for decades. This study aimed to compare the features between subsegmentectomy, segmentectomy and wedge resection for NSCLC.

MATERIALS AND METHODS

NSCLC patients who underwent subsegmentectomy, segmentectomy, or wedge resection between 2014 and 2019 were retrospectively screened. Demographic, radiomic, and perioperative characteristics between patients were compared. Further, log-rank test, univariate and multivariate Cox regression were used for prognostic evaluation.

RESULTS

There were 276, 670, and 494 patients undergoing subsegmentectomy, segmentectomy, and wedge resection, respectively. Patients with segmentectomy and subsegmentectomy had larger tumor sizes and greater distances to the pleura than those with wedge resection. Subsegmentectomy and segmentectomy were more likely to achieve adequate surgical margins than wedge resection (82.0 % vs. 79.5 % vs. 64.7 %, P < 0.001), which was especially true for nodules away from the pleura (80.2 % vs. 81.4 % vs. 55.8 %, P < 0.001). In addition, anatomic resection allowed for more lymph node dissection and required less preoperative localization than wedge reception. Subsegmentectomy preserved about two subsegments than segmentectomy (P < 0.001). The incidence of prolonged air leakage after subsegmentectomy (3.3 %) and wedge (1.8 %) was similar (P = 0.308). Notably, 66.8 % of patients who underwent segmentectomy or subsegmentectomy were considered unsuitable for wedge. During the follow-up (55.1 months), no tumor recurrence or death occurred in patients undergoing subsegmentectomy. No significant recurrence-free survival (P = 0.140) or overall survival (P = 0.370) difference existed between these groups.

CONCLUSIONS

Subsegmentectomy could achieve more adequate surgical margins than wedge resection and showed superiority for deep nodules. Compared to segmentectomy, subsegmentectomy could preserve more lung parenchyma.

Survival and pulmonary function in stage IA non-small cell lung cancer after sublobar resection versus lobectomy: An updated meta-analysis

Traditionally, lobectomy was standard for stage IA non-small-cell lung cancer (NSCLC). Recent RCTs suggest sublobar resection's comparable outcomes. Our meta-analysis, incorporating 30 studies (including four RCTs), assessed sublobar resection's efficacy. Employing a random-effects model and I2 statistics for heterogeneity, we found sublobar resection reduced DFS (HR 1.31, p < 0.01) and OS (HR 1.27, p < 0.01) overall. However, RCT subgroup analysis showed no significant differences in DFS (p = 0.28) or OS (p = 0.62). Sublobar resection is a viable option for well-selected patients.

Segmentectomy versus lobectomy: does FEV1.0 change accurately reflect the postoperative cardiopulmonary function?

OBJECTIVE

The postoperative respiratory function has been compared between lobectomy and segmentectomy based on the resting spirometric change in many previous studies. However, spirometric change has only been assessed in static conditions, and it is unclear whether it accurately reflects the cardiopulmonary function.

METHODS

We used spirometry and a 6-min walk test to evaluate patients who underwent lobectomy and segmentectomy and examined the changes in heart rate (HR), respiratory rate (RR), and saturation of percutaneous oxygen (SpO2) before and after walking between the two groups.

RESULTS

The present study included 24 patients who underwent segmentectomy and 21 who underwent lobectomy. There was no significant difference in the reduction of the median forced expiratory volume in 1 s (FEV1.0) after surgery. In the 6-min walk test, the increase in HR and RR after surgery has no significant differences between lobectomy and segmentectomy (HR: p = 0.372 and RR: p = 0.131). However, the two groups showed a significant difference in the reduction of SpO2 (p < 0.001). In addition, correlation analysis found that the more the number of resected segments, the more the reduction of SpO2 with a statistical significance (p = 0.002).

CONCLUSIONS

Patients who received segmentectomy showed to suppress the reduction of SpO2 with a statistical difference after the 6-min walk test in comparison to those who received lobectomy. These results suggest that segmentectomy has less impact on the cardiopulmonary function and the 6-min walk test is useful for evaluating the postoperative cardiopulmonary function.

Effect of Resected Lung Volume on Pulmonary Function and Residual Lung Volume in Patients Undergoing Segmentectomy: A Retrospective Study

PURPOSE

We elucidated the effects of planned resection volume on postoperative pulmonary function and changes in residual lung volume during segmentectomy.

METHODS

This study included patients who underwent thoracoscopic segmentectomy between January 2017 and December 2022 and met eligibility criteria. Pre- and post-resection spirometry and computed tomography were performed. Three-dimensional reconstructions were performed by using computed tomography images to calculate the volumes of the resected, remaining, and nonoperative side regions. Based on the resected region volume, patients were divided into the higher and lower volume segmentectomy groups. Changes in lung volume and pulmonary function before and after the surgery were comparatively analyzed.

RESULTS

The median percentage of resected lung volume was 10.9%, forming the basis for categorizing patients into the two groups. Postoperative forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) ratios to preoperative measurements in both groups did not differ significantly (FEV1, p = 0.254; FVC, p = 0.777). Postoperative FEV1 and FVC ratios to their predicted postoperative values were significantly higher in the higher volume segmentectomy group than in the lower volume segmentectomy group (FEV1, p = 0003; FVC, p < 0.001). The higher volume segmentectomy group showed significantly greater post-to-preoperative lung volume ratio in overall, contralateral, ipsilateral, residual lobe and residual segment than the lower volume segmentectomy group.

CONCLUSIONS

Postoperative respiratory function did not differ significantly between the higher- and lower-volume segmentectomy groups, indicating improved respiratory function because of substantial postoperative residual lung expansion. Our findings would aid in determining the extent of resection during segmentectomy.

[Impact of the Size and Depth of Pulmonary Nodules on the Surgical Approach for Lung Resection in the Treatment of Early-stage Lung Cancer ≤2 cm]

BACKGROUND

Current studies suggest that for early-stage lung cancers with a component of ground-glass opacity measuring ≤2 cm, sublobar resection is suitable if it ensures adequate margins. However, lobectomy may be necessary for some cases to achieve this. The aim of this study was to explore the impact of size and depth on surgical techniques for wedge resection, segmentectomy, and lobectomy in early-stage lung cancer ≤2 cm, and to determine methods for ensuring a safe resection margin during sublobar resections.

METHODS

Clinical data from 385 patients with early-stage lung cancer ≤2 cm, who underwent lung resection in 2022, were subject to a retrospective analysis, covering three types of procedures: wedge resection, segmentectomy and lobectomy. The depth indicator as the OA value, which is the shortest distance from the inner edge of a pulmonary nodule to the opening of the corresponding bronchus, and the AB value, which is the distance from the inner edge of the nodule to the pleura, were measured. For cases undergoing lobectomy and segmentectomy, three-dimensional computed tomography bronchography and angiography (3D-CTBA) was performed to statistically determine the number of subsegments required for segmentectomy. The cutting margin width for wedge resection and segmentectomy was recorded, as well as the specific subsegments and their quantities removed during lung segmentectomy were documented.

RESULTS

In wedge resection, segmentectomy, and lobectomy, the sizes of pulmonary nodules were (1.08±0.29) cm, (1.31±0.34) cm and (1.50±0.35) cm, respectively, while the depth of the nodules (OA values) was 6.05 (5.26, 6.85) cm, 4.43 (3.27, 5.43) cm and 3.04 (1.80, 4.18) cm for each procedure, showing a progressive increasing trend (P<0.001). The median resection margin width obtained from segmentectomy was 2.50 (1.50, 3.00) cm, significantly greater than the 1.50 (1.15, 2.00) cm from wedge resection (P<0.001). In wedge resections, cases where AB value >2 cm demonstrated a higher proportion of cases with resection margins less than 2 cm compared to those with margins greater than 2 cm (29.03% vs 12.90%, P=0.019). When utilizing the size of the nodule as the criterion for resection margin, the instances with AB value >2 cm continued to show a higher proportion in the ratio of margin distance to tumor size less than 1 (37.50% vs 17.39%, P=0.009). The median number of subsegments for segmentectomy was three, whereas lobectomy cases requiring segmentectomy involved five subsegments (P<0.001).

CONCLUSIONS

The selection of the surgical approach for lung resection is influenced by both the size and depth of pulmonary nodules. This study first confirms that larger portions of lung tissue must be removed for nodules that are deeper and larger to achieve a safe margin. A distance of ≤2 cm from the inner edge of the pulmonary nodule to the nearest pleura may be the ideal indication for performing wedge resection.

Agreement between observed and predicted postoperative forced expiratory volume in one second, forced vital capacity, and diffusing capacity for carbon monoxide after anatomic lung resection

Background

Despite its importance in clinical practice, clinical guideline pathway selection and as an outcome in clinical trials, little work has been undertaken to understand the agreement between expected lung function loss and actual observed values. This is particular pertinent in view of the unexpected findings of JCOG 0802 and CALBG 140503 demonstrating no clinically meaningful difference in lung function loss between the sub-lobar resection and lobectomy arm.

Methods

We performed a retrospective analysis on preoperative and postoperative forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLCO) collated from 158 patients who underwent anatomical lung resection between January 2013 to July 2023. Patient's true preoperative and postoperative lung function was obtained via formal lung function testing while predicted postoperative lung function was derived using the 20-segment counting method. Longitudinal postoperative lung function analysis demonstrated sufficient stability over time. A formal testing of agreement between predicted and true postoperative lung function was undertaken using the Bland and Altman method and graphically demonstrated using scatter plots. We defined a deviation of more than 5% as a clinically minimally important difference.

Results

Scatter plots for effort-dependent measures suggested the tendency for underprediction (observed values were higher than predicted) for FEV1 and FVC but good agreement for DLCO. Formal agreement confirmed mean difference for FEV1 was -9.84% [95% confidence interval (CI): -39.33% to 19.65%], FVC -11.39% (95% CI: -50.14% to 27.36%) and DLCO -4.83% (95% CI: -25.59% to 15.92%).

Conclusions

Our study demonstrated that effort-dependent parameters of lung function including FEV1 and FVC tends to overestimate the amount of lung function loss after anatomic lung resection, clinicians should be cautious in using these measures to determine suitability of surgery based on current established guidelines. However, independent measures such as DLCO demonstrate good agreement suggesting that predicted lung tissue loss is consistent with a 20-segment lung model.

[Indocyanine green fluorescence in thoracoscopic segmentectomy: indications and benefits]

OBJECTIVE

To determine the role of ICG fluorescence in segmentectomies.

MATERIAL AND METHODS

One surgical team performed 178 thoracoscopic anatomical segmentectomies in two hospitals between 2017 and 2023. Of these, 93 (52.2%) patients underwent ICG fluorescence perfusion tests. This study was retrospective and consecutive. Intraoperative and early postoperative results were analyzed. Patients were divided into 3 equal periods. Ventilation and perfusion methods were used to navigate the intersegmental planes in the first period. In the second one, only ventilation methods were used due to the absence of ICG. In the third period, the choice of navigation method was determined by «surgical complexity of segment».

RESULTS

In 74% of patients, surgeries were performed for primary or metastatic lung tumors. The scheduled procedure was performed in all patients. However, 2 ones required lobectomy for total resection. Uneventful postoperative period was observed in 69.7% of patients. Other ones had complications grade I-IIIA. No reoperations or mortality were recorded.

CONCLUSION

ICG perfusion is not inferior to ventilation methods in identification of intersegmental planes. This method is also more convenient for thoracoscopy. ICG fluorescence thoracoscopy is the only method in patients with COPD scheduled for thoracoscopic segmentectomy with two or more intersegmental planes.

Changes in pulmonary function in lung cancer patients after segmentectomy or lobectomy: a retrospective, non-intervention, observation study

OBJECTIVES

Pulmonary segmentectomy (SE) became an increasingly popular method for resection of early-stage lung cancer. This study aims to compare the impact of single SE (SSE), multiple SE (MSE) and lobectomy (LE) on postoperative pulmonary function in patients with NSCLC.

METHODS

Medical records of a total of 1284 patients who underwent LE (n = 493), SSE (n = 558) and MSE (n = 233) at Shanghai Pulmonary Hospital from January 2013 to October, 2020 were retrospectively analysed. Pulmonary function tests (PFTs) were performed preoperatively and 12 months after surgery.

RESULTS

SSE was associated with a significantly smaller decline in the PFT values compared to MSE and LE. There was a poor consistency between the observed and expected (O/E) loss of pulmonary function in all study groups (P < 0.05). Both LE and SE resulted in similar O/E ratios of all PFT parameters (P > 0.05).

CONCLUSIONS

Overall loss of pulmonary function was much greater after LE than after both SSE and MSE. MSE was associated with higher postoperative pulmonary function decline compared to SSE but was still beneficial over LE. Both LE and SE groups had similar PFT loss per segment (P > 0.05).

Sublobar Resections

Sublobar resections are commonly performed operations that have seen an increase in applicability. The sublobar approach, comprising segmentectomy and wedge resections, can provide lung preservation and thus is better tolerated in select patients in comparison to lobectomy. These operations are offered for a variety of benign and malignant lesions. Understanding the indications and technical aspects of these approaches is paramount as improvements in lung cancer screening protocols and the imaging modalities has led to an increase in the detection of early-stage cancer. In this article, we discuss the anatomy, indications, technical approaches, and outcomes for sublobar resection.

Ground glass opacity resection extent assessment trial : A study protocol of multi-institutional, prospective, open-label, randomized phase III trial of minimally invasive segmentectomy versus lobectomy for ground glass opacity (GGO)-containing early-stage invasive lung adenocarcinoma

Background

With widely use of computed tomography (CT) screening, an increasing number of early-stage lung cancers appearing as ground glass opacity (GGO) have been detected. Therefore, attempts have been made to investigate the feasibility of segmentectomy instead of lobectomy for those patients with GGO. However, the two recently released phase III trials failed to distinguish between GGO-containing lesions from pure solid nodules in the inclusion criteria, and the surgical methods did not distinguish between minimally invasive surgery and open thoracotomy. In addition, total lesion size≤ 2cm was taken as the inclusion criterion, instead of the solid part size recommended in the eighth edition of Union for International Cancer Control/International Association for the Study of Lung Cancer/American Joint Committee on Cancer (UICC/IASLC/AJCC) staging system. Hence, this present trial aims to figure out whether minimally invasive segmentectomy shows superiority in perioperative outcomes and non-inferiority in oncological prognosis over minimally invasive lobectomy among patients with GGO-containing clinical stage T1a-T1b lung invasive adenocarcinoma (IADC).

Methods/design

Sample sizes are 1024 patients, who will be randomized into minimally invasive segmentectomy and lobectomy groups . Patients will be collected from 19 hospitals in China. Patients with peripheral mixed ground glass opacity (mGGO) with 0.5cm<total lesion size ≤ 3cm and 0.5cm<solid component size ≤ 2cm in lung window on CT scan are enrolled. The primary endpoint is 5-year recurrence-free survival (RFS). The secondary endpoints are 5-year overall survival (OS), perioperative outcomes and pulmonary function preservation. Kaplan-Meier curves are plotted to compare the survival outcomes between the two arms. Subgroup analyses are also performed to investigate the benefit of segmentectomy among different clinical variables.

Discussions

If the primary endpoint shows at least non-inferiority in 5-year RFS of segmentectomy to lobectomy, minimally invasive segmentectomy can be recommended as an alternative to minimally invasive lobectomy. If second endpoints show non-inferior 5-year OS along with better perioperative outcomes and/or better pulmonary function preservation of segmentectomy compared with lobectomy after the primary endpoint has reached, minimally invasive segmentectomy may become a preferred procedure for patients with GGO-containing clinical stage T1a-T1b IADCs.

Trial registration

Chinese Clinical Trial Registry. Trial registration number: ChiCTR2000037065.

Clinical trial registration

https://www.chictr.org.cn/, identifier ChiCTR2000037065.

Spread through air spaces is a powerful prognostic predictor in patients with completely resected pathological stage I lung adenocarcinoma

PURPOSE

To evaluate the frequency of spread through air spaces (STAS) in patients with early-stage primary lung cancer and to elucidate the association between STAS and various clinicopathological factors.

METHODS

We retrospectively reviewed data from a total of 265 consecutive patients who underwent lobectomy and mediastinal lymph node dissection (172 patients) or sublobar resection (93 patients) for completely resected pathological stage I lung adenocarcinoma. We evaluated clinical variables, including the preoperative serum carcinoembryonic antigen (CEA) level, tumour size, consolidation tumour ratio (CTR), maximum standardized uptake value (SUVmax) on FDG-PET, histological results, presence of STAS and vascular and lymphatic invasion.

RESULTS

The median follow-up time after surgery was 49 months. Eighty-seven patients (32.8 %) had STAS. The overall survival rates of patients in the STAS-positive and STAS-negative groups were 92.7 % and 97.1 % at 3 years, respectively (p = 0.1255), and the recurrence-free survival rates were 82.1 % and 95.9 % at 3 years, respectively (p = 0.0001). STAS was found in 73 patients (42.4 %) in the lobectomy group, which was a significantly higher proportion than the 14 patients (15.1 %) in the sublobar resection group. The STAS-positive group had significantly larger areas of invasion, higher CTRs, preoperative CEA and SUVmax levels, and more lymphatic and vascular invasion. STAS also correlated significantly with large consolidation sizes, larger invasive size, higher CTRs and the presence of a micropapillary pattern. Cox regression analysis after adjustment for important prognostic factors revealed that the presence of STAS was an independent predictor associated with postoperative recurrence, most of which was observed locoregionally.

CONCLUSIONS

STAS was an independent factor associated with postoperative recurrence after lung resection for stage I lung adenocarcinoma. Among stage IA patients, the postoperative outcomes of STAS-positive patients were worse than those of STAS-negative patients and were similar to those of stage IB patients.

Pulmonary function changes after sublobar resection in patients with peripheral non-subpleural nodules

Background

In the treatment of peripheral early-staged lung cancer and benign lesions, segmentectomy and wedge resection are both reliable treatment methods. It is debatable that how much pulmonary function will be lost after different sublobar resection in the treatment of early-staged deep-located peripheral NSCLC (non-small cell lung cancer). The purpose of this study was to explore postoperative pulmonary function changes of sublobar resection in enrolled patients with non-subpleural peripheral nodules.

Methods

We collected clinical data of patients undergoing VATS (video-assisted thoracoscopic surgery) segmentectomy or wedge resection for single nodule. These nodules were confirmed as peripheral non-subpleural nodules by preoperative 3D imaging. Patients were divided into two groups according to the operation procedure. Demographic characteristics, pulmonary function, postoperative outcomes, and others were collected. All data was gathered at the First Affiliated Hospital of Soochow University. Outcomes after wedge resection were compared with those after segmentectomy resection.

Results

A total of 88 patients were included in this study, including 46 patients with VATS wedge resection and 42 patients with VATS segmentectomy. No difference was detected when comparing FEV1 (forced expiratory volume in 1 s) loss between these two groups (17.6 ± 2.1%, wedge resection vs. 19.4 ± 5.4%, segmentectomy, P = 0.176). FVC (forced vital capacity) loss (8.7 ± 2.3%, wedge resection vs. 17.1 ± 2.2%, segmentectomy, P < 0.001) and MVV (maximum ventilatory volume) loss (11.5 ± 3.1%, wedge resection vs. 20.6 ± 7.8%, segmentectomy, P < 0.001) in segmentectomy group was significantly higher than those in wedge resection group. Discrepancies were investigated when comparing duration of surgery (70 ± 22 min, wedge resection vs. 111 ± 52 min, segmentectomy, P = 0.0002), postoperative drainage (85 ± 45 mL, wedge resection vs. 287 ± 672 mL, segmentectomy, P = 0.0123), and treatment hospitalization expenses [35148 ± 889CNY, wedge resection vs. 52,502 (38,276–57,772) CNY, segmentectomy, P < 0.0002]. No significant difference was found between air leak time (1.7 ± 0.7 days, wedge resection vs. 2.5 ± 1.7 days, segmentectomy, P = 0.062) and hospitalization time (2.7 ± 0.7 days, wedge resection vs. 3.5 ± 1.7 days, segmentectomy, P = 0.051).

Conclusions

For patients with peripheral non-subpleural nodules, we observed that patients who underwent wedge resection had less lung function loss than those who underwent segmentectomy when their lung function was reviewed at the 6th month after surgery. Patients undergoing wedge resection had partial advantages over patients with segmental resection in terms of hospitalization cost, operation time and postoperative drainage, etc. Wedge resection, as a treatment for peripheral non-subpleural pulmonary nodules, seemed to have more advantages in preserving patients’ pulmonary function.

Comparison of bronchial methylene blue staining and modified inflation-deflation method in identifying the intersegmental plane during lung segmentectomy

Background

Identification of the intersegmental plane (ISP) is the critical step in lung segmentectomy because of the complicated anatomic variations. Bronchial methylene blue staining was developed by our team in 2015 and is now commonly used at our center, it could rapidly and accurately identify the ISP. In this study, we aimed to compare bronchial methylene blue staining with the modified inflation-deflation method in terms of their perioperative characteristics and to present our experience of the methylene blue method.

Methods

From June 2020 to September 2021, the data of 112 patients with pulmonary ground-glass nodules who underwent segmentectomy by video-assisted thoracoscopic surgery were retrospectively reviewed. Sixty-two patients underwent bronchial methylene blue staining, and 50 patients underwent the modified inflation-deflation method.

Results

Both methods could accurately identify the ISP. The time taken to clearly display the ISP (82.94±28.08 vs. 868.20±145.89 seconds; P<0.001) and the surgical duration (131.69±32.05 vs. 146.08±28.11 minutes; P=0.014) were significantly shorter in the bronchial methylene blue staining group than in the modified inflation-deflation group. There were no significant differences between the two groups in the bleeding volume, drainage time, and length of postoperative hospital stay, as well as in most other perioperative characteristics.

Conclusions

Compared with the modified inflation-deflation method, the bronchial methylene blue staining method can quickly display the ISP and shorten the surgical duration. This method is safe and feasible, can be widely applied during thoracoscopic anatomic segmentectomy.

Pulmonary function changes after uniportal video-assisted thoracoscopic anatomical lung resection

OBJECTIVE

The superiority of segmentectomy over lobectomy with regard to preservation of pulmonary function is controversial. This study aimed to examine changes in pulmonary function after uniportal video-assisted thoracoscopic surgery (VATS) according to the number of resected segments.

METHODS

We retrospectively reviewed 135 consecutive patients who underwent anatomical lung resection via uniportal VATS from April 2015 to December 2020. Pulmonary function loss was evaluated using forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). Patients were grouped according to number of resected segments: one-segment (n = 33), two segments (n = 22), three segments (n = 40), four segments (n = 15), and five segments (n = 25).

RESULTS

Clinical characteristics did not significantly differ between groups, except for tumor size. Mean follow-up was 8.96 ± 3.16 months. FVC loss was significantly greater in five-segment resection (10.8%) than one-segment (0.97%, p = 0.008) and two-segment resections (2.44%, p = 0.040). FEV1 loss was significantly greater in five-segment resection (15.02%) than one-segment (3.83%, p < 0.001), two-segment (4.63%, p = 0.001), and three-segment resections (7.63%, p = 0.007). Mean FVC loss and FEV1 loss increased linearly from one-segment resection to five-segment resection. Mean loss in FVC and FEV1 per segment resected was 2.16% and 3.00%, respectively.

CONCLUSIONS

Anatomical lung resection of fewer segments was associated with better preservation of pulmonary function in patients undergoing uniportal VATS, and function loss was approximately 2%-3% per segment resected with linear relationship.

Progress in three-dimensional computed tomography reconstruction in anatomic pulmonary segmentectomy

The number of minimally invasive surgeries, such as video-assisted thoracoscopic surgery and robot-assisted thoracoscopic surgery, has increased enormously in recent years. More and more relevant studies report that anatomic pulmonary segmentectomy has the same effect as traditional lobectomy in the surgical treatment of early stage non-small cell lung cancer (diameter less than 2.0 cm). Segmentectomy requires sufficient knowledge of the location of the pulmonary nodules, as well as the anatomy of the target segments, blood vessels, and bronchi. With the rapid development of imaging technology and three-dimensional technology, three-dimensional reconstruction has been widely used in the medical field. It can effectively assess the vascular branching patterns, discover the anatomic variations of the blood vessels and bronchi, determine the location of the lesion, and clarify the division of the segments. Therefore, it is helpful for preoperative positioning, surgical planning, preoperative simulation and intraoperative navigation, and provides a reference for formulating an individualized surgical plan. It therefore plays a positive role in anatomic pulmonary segmentectomy. This study reviews the progress made in three-dimensional computed tomography reconstruction in anatomic pulmonary segmentectomy.

What Do We Talk About Now When We Talk About Segmentectomy for GGO?

Segmentectomy has been considered as a compromised procedure in patients with early-stage lung cancer who could not tolerate standard lobectomy. By computed tomography (CT) screening, lung cancers are increasingly detected in earlier stages, especially those appearing as ground glass opacity (GGO)-containing lesions on CT scan. This has led to the revival of segmentectomy as an intentional procedure with the aim of curing selected patients, as GGO-containing lesions represent a special group of diseases that are relatively indolent in nature and seldom have lymphatic involvement. Limited resections, especially anatomical segmentectomy, may, thus, be helpful in reducing perioperative risks and preserving higher pulmonary function for patients while retaining similar oncological outcomes. However, clinical trials focusing specifically on the role of segmentectomy in the treatment of GGO-containing lung cancers are still lacking, especially in the minimally invasive surgery setting. Emerging evidence suggests that for such lesions, the oncological non-inferiority of segmentectomy to standard lobectomymay not be limited to lesions with a size ≤ 2 cm. More importantly, it is still unclear whether segmentectomy could indeed minimize perioperative risks and to what extent it could help preserve higher pulmonary function in good-risk patients with less extent of lung parenchyma resection. Hence, it is critical to reevaluate the efficacies of minimally invasive segmentectomy including not only oncological outcomes but also perioperative results and pulmonary function changes compared with lobectomy in good-risk patients with GGO-containing lung cancers. All these remain to be explored in future studies and robust evidence is still needed to prove that patients would indeed benefit from the combination of segmentectomy and minimally invasive surgery.