Extent of Segmentectomy That Achieves Greater Lung Preservation Than Lobectomy

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.

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.

Feasibility of thoracoscopic monosubsegmentectomy for small ground-glass opacity dominant lung cancer

BACKGROUND

Monosubsegmentectomy (MSS) involves removal of less lung parenchyma than monosegmentectomy (MS) does. However, the clinical efficacy of MSS in lung cancer treatment remains unclear, with concerns regarding insufficient surgical margins and increased complications.

METHODS

Between February 2015 and December 2019, patients who underwent thoracoscopic MSS (n = 126) or MS (n = 678) for small ground-glass opacity (GGO) dominant lung cancer were examined. The primary endpoints were the procedure success rate (defined as resection with a surgical margin ≥2 cm or tumor size) and surgical margin.

RESULTS

There were no significant differences in age, sex, smoking history, or comorbidities between the groups. Both groups achieved a success rate of 100%. No significant group differences were observed in the number of lymph nodes removed (p = 0.060), overall complications (p = 0.147), or major complications (p = 0.450). The MSS group had a smaller surgical margin (median, 17 vs. 21mm, p < 0.001) and longer operative time (median, 138 vs. 130 min, p = 0.005) than the MS group did. Propensity score-matched analysis of 122 pairs of patients revealed consistent results. Surgical margins were further compared based on the number of resected subsegments. The 1 subsegment group had the smallest median surgical margin, followed by the 2 and 3 subsegments groups (17, 20, and 23 mm, p < 0.001).

CONCLUSIONS

Thoracoscopic MSS is an acceptable option for treating patients with small-sized GGO-dominant lung cancer. However, the close surgical margins and prolonged operative time should be considered.

Sublobar resection or lobectomy and postoperative respiratory complications in emphysematous lungs

OBJECTIVES

Pulmonary resection in patients with severe emphysema may impact postoperative respiratory complications. Low-attenuation areas evaluated using three-dimensional computed tomography to assess emphysematous changes are strongly associated with postoperative respiratory complications. Herein, we investigated the relationship between low-attenuation area, the surgical procedure and resected lung volume, which has not been explored in previous studies.

METHODS

We retrospectively evaluated patients with primary or metastatic lung cancer who underwent surgical resection. The low-attenuation area percentage (low-attenuation area/total lung area × 100) and resected lung volume were calculated using three-dimensional computed tomography software, and the relationship with postoperative respiratory complications was analysed.

RESULTS

Postoperative respiratory complications occurred in 66 patients (17%) in the total cohort (n = 383). We set the median value of 1.1% as the cut-off value for low-attenuation area percentage to predict postoperative respiratory complications, which occurred in 24% and 10% of patients with low-attenuation area >1.1% and <1.1%, respectively (P < 0.001). Postoperative respiratory complications occurred in approximately one-third of the patients with low-attenuation area >1.1%, whose resected lung volume was ≥15.8% or ≥5 resected subsegments. Multivariable analysis revealed that sublobar resection was associated with a significantly lower risk of postoperative respiratory complications in patients with low-attenuation area >1.1% (odds ratio 0.4, 95% confidence interval 0.183-0.875).

CONCLUSIONS

Emphysema is a risk factor for postoperative respiratory complications, and lobectomy is an independent predictive risk factor. Preserving more lung parenchyma may yield better short-term prognoses in patients with emphysematous lungs.

Predicting 1-year non-cancer-related adverse events after lung resection

OBJECTIVES

Assessing the risk for non-cancer-related outcomes following lung cancer surgery is crucial for high-risk patients. This study examined non-cancer-related adverse events within 1 year after lung resection, emphasizing the role of resected lung volume and postoperative atrial fibrillation (POAF).

METHODS

We conducted a retrospective analysis of 460 patients who underwent anatomical lung resection for malignant lung tumours. We assessed perioperative factors, such as the number of resected subsegments and POAF, as potential predictors of 1-year non-cancer-related adverse events. Additionally, we validated a previously published nomogram for predicting POAF.

RESULTS

One-year non-cancer-related adverse events occurred in 20% of patients. Multivariable analysis identified higher age, lower percentage-predicted forced expiratory volume in 1 second, greater number of resected subsegments and POAF as independent predictors of these adverse events. The incidence of POAF was 8.5%, with higher age, history of atrial fibrillation, and open thoracotomy as independent predictors. A temporal link between POAF and other severe postoperative complications was observed, as 71% of POAF cases preceded other complications. The nomogram's predicted risk for POAF was associated well with the actual incidence.

CONCLUSIONS

Resected lung volume and POAF are statistically significant factors associated with non-cancer-related outcomes after lung resection. Minimizing resected lung volume when oncologically and technically feasible, along with identifying patients at risk for POAF, may contribute to improved postoperative outcomes. Our results have implications for risk stratification and preoperative decision-making in lung cancer surgery.

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.

Lobectomy versus segmentectomy: a propensity score-matched comparison of postoperative complications, pulmonary function and prognosis

OBJECTIVES

To demonstrate the differences in clinical outcomes between lobectomy and segmentectomy for non-small cell lung cancer using propensity score matching.

METHODS

A single-centre, retrospective, matched cohort study was conducted in clinical T1N0M0 non-small cell lung cancer patients treated by surgery between 2012 and 2019. Differences in freedom from recurrence, overall survival, postoperative complications, chest drainage and preservation of pulmonary function between lobectomy and segmentectomy were evaluated using the propensity score model. Matched variables of patients were age, sex, comorbidity index and pulmonary function. Matched variables of tumours were tumour size, T-stage, fluorodeoxyglucose uptake on positron emission tomography, histopathology, lobe site and tumour distance ratio from the hilum.

RESULTS

Of the 112 patients treated by lobectomy and 233 patients treated by segmentectomy, 93 patients each from both groups were selected after the matching. The median tumour distance ratio from hilum was 0.7 in lobectomy and 0.8 in segmentectomy group (P = 0.59), i.e. almost outer third tumour location. There were no significant differences in freedom from recurrence (P = 0.38), overall survival (P = 0.51), postoperative complications (P = 0.94), drainage period (P = 0.53) and prolonged air leakage (P = 0.82) between the two. Median preservation of pulmonary function was 93.2% after segmentectomy, which was significantly higher than 85.9% after lobectomy (P < 0.001).

CONCLUSIONS

Freedom from recurrence, overall survival, postoperative complications and chest drainage were similar between segmentectomy and lobectomy. Segmentectomy could be one of the options for clinical T1N0M0 non-small cell lung cancer located outer third as well as being able to preserve pulmonary function better than lobectomy.

CLINICAL TRIAL REGISTRATION

Pulmonary function after segmentectomy versus lobectomy in patients with early-stage non-small-cell lung cancer: a meta-analysis

Objective

Segmentectomy is widely performed for early-stage lung cancer. However, the effects of segmentectomy versus lobectomy on pulmonary function remain unclear. We performed a meta-analysis with the aim of comparing segmentectomy and lobectomy in terms of preservation of pulmonary function in patients with early-stage non-small-cell lung cancer (NSCLC).

Methods

We conducted a literature search of PubMed using the terms ‘pulmonary function’ AND ‘segmentectomy’ AND ‘lobectomy’. The primary outcomes of interest were the forced expiratory volume in 1 second (FEV1), FEV1 as percent of predicted (%FEV1), change in FEV1 (Δ%FEV1), and the ratio of postoperative to preoperative FEV1.

Results

Thirteen studies comprising 2027 patients met the inclusion and exclusion criteria and were included for analysis, including 787 patients in the segmentectomy group and 1240 patients in the lobectomy group. Patients in the segmentectomy group showed significantly better preservation of FEV1 and %FEV1 compared with the lobectomy group. The reduction in FEV1 after surgery was significantly less in the segmentectomy group compared with the lobectomy group, and Δ%FEV1 was significantly higher in the segmentectomy group than in the lobectomy group.

Conclusion

Segmentectomy results in better preservation of pulmonary function compared with lobectomy in patients with early-stage NSCLC.