Sleeve lobectomy versus lobectomy for primary treatment of non‐small–cell lung cancer: A single‐center retrospective analysis

It is unclear how much additional perioperative risk a sleeve lobectomy could pose in comparison to lobectomy. The objective of this analysis was to compare the complication rate, 30‐day mortality, and overall survival between lobectomy and sleeve lobectomy without prior neoadjuvant treatment in non‐small–cell lung cancer (NSCLC).


| Surgical technique
Standard lobectomy was performed by means of anterolateral thoracotomy in 86% cases. Video-assisted thoracoscopy (14%) was performed for tumors less than 4 cm in size. In open lobectomy, bronchial closure was performed by double row continuous absorbable 4-0 PDS suture. A linear Endo-GIA stapling device was used during thoracoscopic lobectomy for vascular and bronchial closure. The anastomoses after sleeve resection were sutured with PDS 4-0 monofile absorbable continuous double-armed suture. In every case, complete hilar and mediastinal lymph node dissection was performed with the dissection of levels 2,4,7,8,9, and 10 on the right side and of levels 4,5,6,7,8,9, and 10 on the left side.
Angioplastic or intrapericardial resections were added when necessary.

| Postoperative management
All patients undergoing sleeve lobectomy were treated with inhalative tobramycin for 7 days as infection prophylaxis according to our internal standard management. 6 A bronchoscopic anastomosis evaluation after sleeve lobectomy was performed routinely on the 7th postoperative day. 7 The results were divided into five grades according to our formerly published classification of bronchial anastomosis healing. 7 In case of bronchial insufficiency, further diagnostic and antibiotic or surgical treatment were indicated. In the standard lobectomy group, postoperative bronchoscopy was performed only when clinical suspicion of bronchial stump insufficiency arose.

| Statistical analysis
The statistical analysis was performed using the MedCalc program, version 14.8.1.0. Overall survival was calculated as the time between surgery and death from any cause. Survival was estimated using the Kaplan-Meier method, and survival comparison between groups was performed using log-rank analysis. Univariate logistic regression analyses were used to determine the impact of patient characteristics on inhospital complications. A p-value < .05 was considered statistically significant.

| Morbidity and mortality
Postoperative complications occurred in n = 148 (29.24%) patients of the lobectomy group and in n = 76 (30.15%) of the sleeve group. All complications are depicted in  Table 1 and recurrence rates comparatively in Figure 1. The recurrence status could not be determined reliably for three patients from the lobectomy group. 5-year survival was 69.97% for the lobectomy group and 65.59% for the sleeve group (p = .829) ( Figure 2). Due to the distribution difference between the two groups regarding tumor stage, we calculated the long-term survival (5-year survival probability) for Stages I and II (early stages) patients, such as for Stage IIIA,B patients (advanced stages) (Figures 3 and 4). There was no statistically significant difference between the two groups.

| DISCUSSION
The indication for sleeve resection is determined by the central localization and extension of the tumor into the main bronchus or parabronchial lymph node metastases with bronchial or mucosal infiltration.
The surgical alternative remains pneumonectomy, which is accompanied by higher morbidity and mortality rates and may be not applicable due to impaired cardio-pulmonary function. 4 Although it has been reported that pneumonectomy patients probably have more advanced disease, long-term survival and local control are significantly better when complete resection can be achieved by sleeve lobectomy. 8  | 557 the undoubtedly risk-associated pneumonectomy but also to the standard of surgical care for NSCLC, the lobectomy.
Maurizi et al summarized postoperative complication rates after sleeve lobectomy ranging between 7.4% and 50%. 11 In our collective, the total number of postoperative complications after sleeve lobectomy was comparable and sometimes even lower than after a lobectomy. Lower pneumonia and respiratory insufficiency rates in the sleeve lobectomy group could be also attributed to routine postoperative tobramycin inhalation in our institution. The average 30-day mortality after sleeve lobectomy ranges from 2.14% to 12.6% and is reported at about 3% for lobectomy in high-volume thoracic surgery centers. [13][14][15] In our collective, 30-day mortality after sleeve resection was documented at 4.76% and at 0.78% after standard lobectomy. Both ratios are interestingly low compared to other reports. These numbers support the known fact that, even with well-established perioperative care, sleeve lobectomy is more challenging than standard lobectomy. It presents more severe and fatal complications when they arise. An additional potentially fatal complication after sleeve lobectomy is anastomotic insufficiency. 14  The groups differ significantly in terms of their oncological preoperative situation. Tumors in the sleeve lobectomy group were more advanced.
The nodal status in the sleeve lobectomy group was also higher. Such a comparison is, however, inevitable due to a lack of prospective randomized data and is also being reported in pneumonectomy versus sleeve lobectomy as well as lobectomy versus sleeve lobectomy studies from other institutions. 14,17

| CONCLUSION
Sleeve lobectomy for primary surgical treatment of NSCLC without prior neoadjuvant treatment has comparable perioperative complications with standard lobectomy. Even though 30-day mortality after sleeve lobectomy was higher in our patient collective, sleeve lobectomy is comparable to lobectomy in terms of oncological radicality and overall survival.

ACKNOWLEDGMENTS
Open access funding enabled and organized by Projekt DEAL.