Feasibility and Safety of Uniportal Thoracoscopic Segmentectomy Using a Unidirectional Dissection Approach without Dissecting a Fissure.

Background: Few original articles describe the perioperative outcomes of uniportal thoracoscopic segmentectomy using a unidirectional dissection approach. In this retrospective study, we evaluated the feasibility and safety of this procedure. Methods: This study included 119 patients who underwent uniportal thoracoscopic segmentectomy in our department between February 2019 and December 2022. The patients were divided into unidirectional (group U, n = 28) and conventional (group C, n = 91) dissection approach groups. While the dominant pulmonary vessels and bronchi were transected at the hilum without dissecting a fissure in the unidirectional (U) group, the dominant pulmonary artery was exposed and divided at a fissure in the conventional (C) group. Patient characteristics and perioperative outcomes were compared between groups U and C. Results: The proportions of simple and complex segmentectomies were statistically similar between the groups. The operating time was shorter (group U: 110 [interqurtile range: 90-140] min, group C: 135 [interqurtile range: 105-166] min, p = 0.012) and there was less blood loss (group U: 0 [interqurtile range: 0-0] g, group C: 0 [interqurtile range: 0-50] g, p = 0.003) in group U than in group C. However, there were no significant intergroup differences in other perioperative outcomes. Conclusions: The unidirectional dissection approach in uniportal thoracoscopic pulmonary segmentectomy is safe and feasible and enables a smoother operation.

[Gefitinib Monotherapy Afforded Long-Term Survival of an Octogenarian Patient with a Postoperative Recurrence of a Pulmonary Adenocarcinoma-A Case Report].

An 83-year-old(at the time of postoperative recurrence)female clinically diagnosed with primary lung cancer underwent right upper lobectomy and lymph node dissection(ND2a-2). Postoperative pathological staging revealed a Stage ⅠB (pT2aN0M0)adenocarcinoma that was EGFR mutation-positive(exon 21: L858R). Fifty-one months after surgery, the patient developed a mediastinal lymph node metastasis, and radiotherapy was delivered. Next, gefitinib(250 mg daily)was prescribed as first-line therapy. She developed mild anemia but we took a wait-and-see approach. A complete response was evident after 58 months of monotherapy. However, she then developed grade 3 anemia(Hb 6.2 g/dL)and gefitinib was discontinued. She requested(and received)follow-up computed tomography. No progressive disease was evident, but she died of non-cancer disease 16 months after discontinuation of gefitinib(thus 125 months after surgery and 74 months after the postoperative recurrence). Thus, we here present an unusual case. Gefitinib monotherapy afforded long-term survival of an octogenarian patient with a postoperative recurrence of a pulmonary adenocarcinoma.

[Recurrent Postoperative Lung Cancer with Tumor Shrinkage after Discontinuation of Pembrolizumab-A Case Report].

Our patient was a 41-year-old man with non-small cell lung cancer of grade cT3N2M0 and clinical Stage ⅢA. After induction chemoradiotherapy(weekly CBDCA plus PTX[5 courses]and concurrent radiation of 50 Gy, left upper lobectomy with lymph node dissection(ND2a-1)was performed. The postoperative pathological findings were large cell carcinoma, ypT2aN2M0, Stage ⅢA, with complete resection; the PD-L1 tumor proportion score was 50 to 74%. Consolidation chemotherapy( triweekly CBDCA plus PTX, 1 course)followed. Twelve months after surgery, he developed mediastinal lymph node recurrence(#4L), and pembrolizumab was administered every 3 weeks as a first-line treatment. Complete response was evident after 3 courses; thus, we continued this monotherapy. After 35 courses(24 months)of pembrolizumab, we discontinued the regimen. Twenty-two months later, the disease has not progressed. The patient is being followed-up in our outpatient department. We report a case of recurrent postoperative lung cancer with continuous tumor shrinkage after discontinuation of pembrolizumab.

[Multidisciplinary Treatment for Postoperative Recurrent Patients-Report of a Long-Term Survivor].

We present a long-term survivor who received multidisciplinary treatment for a postoperative recurrence. A 52-year-old female who had been clinically diagnosed with primary lung cancer underwent a right lower lobectomy, middle lobe wedge resection, and lymph node dissection(ND2a-1), and was pathologically diagnosed with primary pulmonary papillary adenocarcinoma( pT3N0M0, Stage ⅡB)positive for a sensitizing EGFR mutation(L858R). The patient was given UFT as postoperative adjuvant chemotherapy for 2 years. During the follow-up, multiple pulmonary metastases occurred in postoperative month 44. Gefitinib was administered as the first-line treatment, which resulted in a complete response for 30 months. Then, stereotactic radiotherapy was administered for 3 brain metastases, and multiple pulmonary metastases were treated with cisplatin plus pemetrexed and carboplatin plus pemetrexed for PD, but an adverse event occurred. Therefore, pemetrexed monotherapy was administered as a fourth-line treatment for 5 months. Then, afatinib, nivolumab, docetaxel, osimertinib, S-1, pembrolizumab, and atezolizumab(11th-line treatment)were administered with each PD or new lesion. Finally, the best supportive care was administered and she died on postoperative month 134, which was post-recurrent month 90.

[Video-assisted Thoracoscopic Total Pleural Adhesiolysis:Tips and Pitfalls].

PURPOSES: Here, we present the tips and pitfalls of video-assisted thoracoscopic( VATS) total pleural adhesiolysis( TPA), determined on an empirical basis. PATIENTS AND METHODS: From 2012 to 2020, VATS-TPA was performed in 33 patients undergoing pulmonary anatomic lung resection at our institute. The basic procedure was as follows:after peeling off the area of pleural adhesion surrounding the surgical ports using the fingers, the thoracoscope was inserted into the thorax and the adhesions in other areas were peeled off under thoracoscopic guidance. RESULTS: The adhesiolysis group had a longer operating time, greater blood loss, and higher rate of conversion to thoracotomy compared to the non-adhesiolysis group. However, the results were acceptable considering the extra manipulation for adhesiolysis. CONCLUSIONS: VATS-TPA is a necessary component of the standard surgical procedure for general thoracic surgeons in cases of total pleural adhesion.

Uniportal thoracoscopic mediastinal lymphadenectomy using appropriate surgical steps.

Background: Although lymphadenectomies play an important role in the surgical treatment of patients with non-small cell lung cancer (NSCLC), the quality of lymphadenectomies via a uniportal approach has only been evaluated in a few studies. We describe the surgical steps for a mediastinal lymphadenectomy via uniportal video-assisted thoracoscopic surgery (uVATS) and compare the quality of mediastinal lymphadenectomies using uVATS versus multiportal video-assisted thoracoscopic surgery (mVATS). Methods: Between April 2017 and January 2023, we analyzed data from 304 patients with NSCLC who underwent (bi-)lobectomy with nodal dissection (ND)2a-1 or greater lymphadenectomy via uVATS or mVATS. We compared patient characteristics and perioperative results, including the number of harvested lymph nodes (LNs), between the two approaches. In addition, the factors associated with N-upstage were identified. Results: No significant differences in the total number of harvested LNs were detected between the two approaches. Significantly more LN#2R/4R zone LNs were harvested in the uVATS group compared with the number harvested in the mVATS group [uVATS group: 8.5, interquartile range (IQR), 5-12.3; mVATS group: 7, IQR, 5-9, P=0.0177], while no significant differences in total nodes or nodes harvested in other zones were detected. Multivariable analysis revealed that pathologic invasion size [odds ratio: 1.0200, 95% confidence interval (CI): 1.0100-1.0400, P=0.0050], but not approach (uVATS, odds ratio: 0.6240, 95% CI: 0.3160-1.2300, P=0.1750), significantly contributed to N factor upstages. Conclusions: The use of appropriate surgical steps enabled us to achieve similar quality lymphadenectomies via mVATS or uVATS.

Standardization of intra- and peri-operative management to reduce postoperative drainage time after major thoracoscopic pulmonary resections.

Background: It is important to reduce the postoperative drainage time after thoracic surgery to relieve postoperative pain and facilitate patient mobilization. We standardized intra- and peri-operative management of major, thoracoscopic pulmonary resections in February 2019. In this study, we investigated whether this standardization reduced the postoperative drainage time. Moreover, we examined how such management affected re-admission within 30 days after operation (because of pleural complications). Methods: Between May 2012 and February 2022, 815 patients with malignant or benign disease underwent major thoracoscopic pulmonary resections in our department. The patients were classified into two groups: those who received standardized management (n=352) and those who did not (n=463). After propensity score-matching, we compared characteristics and perioperative results between the two groups (n=234 in each group) by univariate analysis. The factors affecting postoperative drainage time and re-admission within 30 days after operation (because of pleural complications) were evaluated via multivariate analysis. Standardized management was as follows: (I) intraoperatively, any dense fissures were left untreated to avoid postoperative air leakage. A fissureless or unidirectional dissection technique served as an alternative; pulmonary vessels and bronchi were divided at the hilum in patients with dense fissures. (II) The chest drain was removed when air leakage ceased, regardless of the fluid volume or surgeon's preference. Results: The standardized management group evidenced superior results in terms of operative time (P<0.0001) and postoperative drainage time (P<0.0001). There were no significant differences in the remaining perioperative parameters. Moreover, standardized management significantly reduced postoperative drainage time, as revealed by multivariate analysis [estimated regression coefficient: -0.47; 95% confidence interval (CI): -0.78 to -0.16; P=0.003]. Moreover, standardized management did not significantly increase re-admission (because of pleural complications) [odds ratio (OR) =1.76; 95% CI: 0.557 to 5.58; P=0.34]. Conclusions: Standardized intra- and peri-operative management significantly reduced the postoperative drainage time after major thoracoscopic pulmonary resections, without increasing re-admissions within 30 days among patients with pleural complications caused by insufficient drainage. Surgeons must master a fissureless or a unidirectional dissection technique, avoid dissection of fused fissures, and apply standardized perioperative drainage management.

Feasibility of tubeless thoracoscopic bullectomy in primary spontaneous pneumothorax patients.

OBJECTIVES: Although early removal of postoperative chest drains can facilitate postoperative recovery, there are risks of undetected bleeding and a need for re-drainage to treat delayed pulmonary air leaks. In this study, we aimed to prospectively examine the feasibility of tubeless thoracoscopic bullectomy in primary spontaneous pneumothorax (PSP) patients. METHODS: Between January 2021 and November 2021, 30 PSP patients were enrolled in this prospective study. The absence of air leakage was confirmed and radiographic evidence of lung expansion was acquired; the tube was then removed in the operating room. The primary endpoint was postoperative air leakage requiring re-drainage among patients who underwent tube removal in the operating room. The secondary endpoints were postoperative pain (numerical rating scale) on postoperative days (PODs) 1, 7, and 28, morbidity, and postoperative hospitalization time. RESULTS: Four (13.3%) patients were excluded because of underlying pulmonary disease (n = 2) and air leaks (n = 2) detected in the operating room. Chest drainage tubes were removed in the operating room for the remaining 26 patients; none of them required re-drainage. The mean postoperative hospitalization time was 1.2 ± 0.4 days. The mean numerical rating scale scores were 4.2 ± 2 (median: 4.5), 1.6 ± 1.6 (median: 1), and 0.4 ± 0.8 (median: 0) on PODs 1, 7, and 28, respectively. Only one case of hemoptysis occurred as a postoperative complication. CONCLUSIONS: Tubeless thoracoscopic bullectomy for PSP is feasible and may reduce the postoperative hospitalization time; however, it does not significantly reduce pain on POD1.

Supervision by an experienced surgeon can reduce the learning curve of uniportal thoracoscopic lobectomy.

Background: This retrospective study was performed to investigate the learning curve of uniportal thoracoscopic lobectomy with ND2a-1 or greater lymphadenectomy for two senior surgeons, and to evaluate how supervision affected the learning curve. Methods: Between February 2019 and January 2022, 140 patients with primary lung cancer underwent uniportal thoracoscopic lobectomy with ND2a-1 or greater lymphadenectomy in our department. Two senior surgeons (HI and NM) performed most of the operations, with junior surgeons performing the rest. HI initiated this surgical method in our department and supervised all operations performed by other surgeons. Patient characteristics and perioperative outcomes were reviewed, and the learning curve was evaluated based on operative time and the cumulative sum method (CUSUMOT). Results: No significant differences were observed in patient characteristics or perioperative outcomes between groups. Three distinct learning curve phases were identified for each senior surgeon: HI, cases 1-21, cases 22-40, cases 41-71; NM cases 1-16, cases 17-30, cases 31-49. For HI, the rate of conversion to thoracotomy was significantly higher in the initial phase (14.3%, P=0.04) although other perioperative outcomes were equivalent between phases. For NM, while the duration of postoperative drainage was significantly shorter in phase 2 and phase 3 (P=0.026), other perioperative outcomes, including conversion rate (5.3-7.1%), were equivalent between phases. Conclusions: Supervision by an experienced surgeon was important for avoiding conversion to thoracotomy during the initial period, and facilitated the surgeon rapidly gaining proficiency with the surgical method.

Early chest drain removal on the day of uniportal thoracoscopic segmentectomy.

OBJECTIVE: Although early removal of postoperative chest drains can facilitate recovery, it can be difficult to achieve in segmentectomy due to the management of air leakage in intersegmental planes. This study prospectively examined the feasibility of drain removal on the same day of uniportal thoracoscopic segmentectomy. METHODS: Twenty patients who underwent uniportal thoracoscopic segmentectomy between July 2021 and May 2022 were enrolled in this prospective study. The indications for drain removal on the day of surgery were absence of air leakage in an intraoperative sealing test, radiographic evidence of lung expansion, and continuous absence of air leakage via a drainage bottle for 4 h after the operation. The primary endpoint was rate of the patients who required re-drainage after the postoperative drainage tube was removed on the day of surgery. The secondary end points were postoperative pain evaluated using a numerical rating scale on postoperative days 1, 7, and 28; morbidity; and postoperative hospitalization period. RESULTS: Fifteen patients successfully underwent drain removal on the day of surgery. None required re-drainage. The mean postoperative hospitalization period was 2.3 ± 1.7 days. Overall, 12 of the 15 (80%) patients were discharged on postoperative day 1 or 2. The mean numerical rating scale scores were 1.2 ± 1.6, 0.4 ± 0.7, and 0.4 ± 1.5 on postoperative days 1, 7, and 28, respectively. CONCLUSION: In uniportal thoracoscopic segmentectomy, drain removal on the day of surgery is feasible and may reduce pain on postoperative day 1.

Learning curve for uniportal thoracoscopic pulmonary segmentectomy: how many procedures are required to acquire expertise?

Background: Minimally invasive surgeries are increasingly being performed. However, few studies have evaluated the learning curve for uniportal thoracoscopic segmentectomies. Therefore, we investigated the learning curve for uniportal thoracoscopic segmentectomy in our department. Methods: We retrospectively reviewed the clinical data of consecutive patients who underwent uniportal thoracoscopic segmentectomy at our institution between February 2019 and January 2022. Two senior surgeons [Hitoshi Igai (H.I.) and Natsumi Matsuura (N.M.)] performed all of the surgeries. H.I. introduced uniportal thoracoscopic segmentectomy in our department and supervised N.M. performing this operation. Resident surgeons participated in the operations as assistants. The learning curve for uniportal thoracoscopic segmentectomy was evaluated on the basis of operative time and cumulative sum (CUSUMOT). Results: The entire team, including resident surgeons, completed the learning curve by performing 60 surgeries. The learning curve consisted of three phases: initial learning (60 surgeries), accumulation of competence (16 surgeries), and acquisition of expertise (17 surgeries), respectively. The operative time, blood loss, postoperative drainage, and postoperative hospitalization time significantly improved across the phases. N.M. completed the initial learning curve faster than H.I. (16 and 29 surgeries, respectively). Conclusions: Under supervision by an experienced surgeon, a team successfully completed the learning curve for uniportal thoracoscopic segmentectomy and achieved good perioperative outcomes, which indicates the importance of appropriate supervision for acquiring expertise for this surgery.

Comparison of the Learning Curve between Uniportal and Robotic Thoracoscopic Approaches in Pulmonary Segmentectomy during the Implementation Period Using Cumulative Sum Analysis.

BACKGROUND: The aim of this retrospective study was to compare the learning curve and perioperative outcomes between the two approaches uVATS and RATS during their implementation periods. METHODS: The uVATS group included 77 consecutive uVATS segmentectomies performed by HI between February 2019 and June 2022, while the RATS group included 30 between July 2022 and September 2023. The patient characteristics, perioperative outcomes, and learning curves were compared between the two groups. The learning curve was evaluated using operative time and cumulative sum (CUSUMOT) analysis. RESULTS: Most patient characteristics and perioperative outcomes were equivalent between the two groups. In the uVATS group, after a positive slope was observed until the 14th case (initial period), a plateau was observed until the 38th case (stable period). Finally, a negative slope was observed after the 38th case (proficiency period). In the RATS group, after a positive slope was observed until the 16th case (initial period), a plateau was observed until the 22nd case (stable period). Finally, a negative slope was observed after the 22nd case (proficiency period). CONCLUSIONS: In segmentectomy, a surgeon reached the proficiency period earlier in RATS than in uVATS, although the trends to the stable period were similar.

Novel quantitative immunohistochemical analysis for evaluating PD-L1 expression with phosphor-integrated dots for predicting the efficacy of patients with cancer treated with immune checkpoint inhibitors.

Introduction: Programmed cell death ligand 1 (PD-L1) expression in tumor tissues is measured as a predictor of the therapeutic efficacy of immune checkpoint inhibitors (ICIs) in many cancer types. PD-L1 expression is evaluated by immunohistochemical staining using 3,3´-diaminobenzidine (DAB) chronogenesis (IHC-DAB); however, quantitative and reproducibility issues remain. We focused on a highly sensitive quantitative immunohistochemical method using phosphor-integrated dots (PIDs), which are fluorescent nanoparticles, and evaluated PD-L1 expression between the PID method and conventional DAB method. Methods: In total, 155 patients with metastatic or recurrent cancer treated with ICIs were enrolled from four university hospitals. Tumor tissue specimens collected before treatment were subjected to immunohistochemical staining with both the PID and conventional DAB methods to evaluate PD-L1 protein expression. Results: PD-L1 expression assessed using the PID and DAB methods was positively correlated. We quantified PD-L1 expression using the PID method and calculated PD-L1 PID scores. The PID score was significantly higher in the responder group than in the non-responder group. Survival analysis demonstrated that PD-L1 expression evaluated using the IHC-DAB method was not associated with progression-free survival (PFS) or overall survival (OS). Yet, PFS and OS were strikingly prolonged in the high PD-L1 PID score group. Conclusion: Quantification of PD-L1 expression as a PID score was more effective in predicting the treatment efficacy and prognosis of patients with cancer treated with ICIs. The quantitative evaluation of PD-L1 expression using the PID method is a novel strategy for protein detection. It is highly significant that the PID method was able to identify a group of patients with a favorable prognosis who could not be identified by the conventional DAB method.

Novel thoracoscopic segmentectomy combining preoperative three-dimensional image simulation and intravenous administration of indocyanine green.

OBJECTIVES: The aim of this study is to assess prospectively the validity and feasibility of segmentectomy using preoperative simulation and intravenous indocyanine green (ICG) with near-infrared (NIR) light thoracoscope to ensure a sufficient surgical margin. METHODS: This study was a prospective, single-centre, phase II, feasibility study. From February to July 2021, 20 patients were enrolled in this study. All patients underwent preoperative three-dimensional computed tomography angiography and bronchography using simulation software. The dominant pulmonary artery of the targeted segment was selected to determine the dissection line and measure the surgical margin to the tumour. Intraoperatively, after the planned dissection of the pulmonary artery, ICG (0.3 mg/kg) was administered intravenously and observed with NIR, and dissection was performed along the line determined by preoperative simulation. Postoperatively, the pathological margin was compared with the simulation margin. RESULTS: All surgeries were performed via an uniport (3.5-4.0-cm skin incision). The regions of segmentectomy were S2, S3, S6, S9 + 10 and S10 of the right side and S1 + 2 + 3, S3, S3 + 4 + 5, S6 and S8 of the left side. The difference between the simulation margin and the pathological margin was not significant (simulation 30.5 ± 10.1 vs pathological 31.0 ± 11.0 mm, P = 0.801). The simulation margin was well correlated with the pathological margin (R2 = 0.677). The proportion of cases successfully achieving the pathological margin of error of plus or minus 10 mm of the simulation margin was 90% (18 of 20 cases). CONCLUSIONS: The combination of preoperative three-dimensional computed tomography simulation and ICG-NIR was effective for securing a sufficient margin in segmentectomy.

Uniportal thoracoscopic pulmonary segmentectomy provides good perioperative results and early postoperative recovery.

Background: Although video-assisted thoracoscopic surgery (VATS) segmentectomy has become widespread, the advantage of uniportal VATS (U-VATS) segmentectomy over multiportal VATS (M-VATS) remains controversial. The purpose of this study was to verify the safety and usefulness of U-VATS segmentectomy compared with conventional hybrid/multiportal segmentectomy. Methods: Here, we retrospectively reviewed the data from anatomical pulmonary segmentectomy cases in a single institution from March 2010 to March 2021. Patients were divided into the U-VATS and hybrid/multiportal VATS (H/M-VATS) groups. Perioperative results were compared between the groups after matching for patient background characteristics. In addition, cases of complex segmentectomy were selected from each group and compared in terms of perioperative results. Results: A total of 180 patients underwent pulmonary segmentectomy during the study period at this institution, comprising 57 cases in the U-VATS group and 123 cases in the H/M-VATS group. After matching for age, sex, disease, tumor location, and type of segmentectomy, no significant differences between the groups were seen in blood loss, major intraoperative bleeding, rate of conversion to thoracotomy, postoperative complications, or re-hospitalization within 30 days after discharge. Operation time (141±46 vs. 174±45 min, P<0.001), postoperative drainage duration (1.5±1.2 vs. 2.3±1.8 days, P=0.007), and postoperative hospital stay (3.4±2.0 vs. 4.6±2.5 days, P=0.006) were significantly lower in the U-VATS group. Subgroup analysis of the complex segmentectomy cases also revealed that operation time (146±34 vs. 185±47 min, P<0.001), postoperative drainage duration (1.5±1.3 vs. 2.2±1.2 days, P=0.021), and postoperative hospital stay (3.0±1.4 vs. 4.9±2.1 days, P<0.001) were significantly reduced in the U-VATS group. Conclusions: U-VATS segmentectomy appears as safe and feasible as H/M-VATS segmentectomy. An experienced surgeon can make a smooth transition to U-VATS.

A dense fissure is not a contra-indication for uniportal thoracoscopic lobectomy.

Background: A dense fissure is a main cause of a postoperative prolonged air leak (PAL). Such a fissure, if exposed, sometimes incidentally injures the pulmonary artery. We investigated whether uniportal thoracoscopic lobectomy which is considered technically more difficult than the conventional multiportal approach was appropriate for patients with dense fissures. Methods: From February 2019 to January 2022, 140 patients with primary lung cancer underwent uniportal thoracoscopic lobectomy with ≥ ND2a-1 lymphadenectomy. Patients were divided into those with dense (n=22) and separated (n=118) fissures. All dense fissures were treated using a fissureless technique without exposure of the pulmonary artery. We compared the characteristics and perioperative results of the two groups. We used multivariate analysis to identify factors predictive of PAL. Results: Although dense fissures were significantly associated with right upper lobectomies, the other patient characteristics and perioperative results were similar between the two groups. No significant pulmonary artery injuries occurred in the fissureless group. In subgroup analyses of right upper lobectomy patients, we found no other significant between-group differences in patient characteristics or perioperative results. In multivariate analyses, right upper lobectomy [odds ratio (OR): 0.047, 95% confidence interval (CI): 0.0044-0.49, P=0.011] or smoking index (OR: 1.03, 95% CI: 1-1.07, P=0.048) was the factor predictive of PAL. Conclusions: A dense fissure is not a contraindication for uniportal thoracoscopic lobectomy using the fissureless technique, which is thus safe.

A "Catlike Cry" as a Symptom of Congenital Tracheoesophageal Fistula.

Congenital tracheoesophageal fistula is usually diagnosed at an early age, but may remain undetected into adulthood if atresia is absent and if the fistula is small. A tracheoesophageal fistula should be suspected in patients with unexplained episodes of respiratory distress or pneumonia; however, more subtle signs can be an important symptom for early recognition of the disease. Ono's sign is a well-known symptom of tracheoesophageal fistula, characterized by paroxysmal coughing triggered by swallowing of fluids. In the present case, air movement between the esophagus and the trachea through the fistula caused a high-pitched sound, which the patient described as a "catlike cry." The high-pitched sound ceased after surgical closure of the fistula. We report here the symptom of "catlike cry" as one manifestation of tracheoesophageal fistula.

Superior Lingular S4 Segmentectomy.

Although segmentectomy has become a routine procedure, atypical segmentectomies are less popular than their typical counterparts, probably because anatomic and surgical data are lacking. The left superior lingular S4 segment is considered relatively small, usually resected along with other segments. However S4 segment size varies among patients, and resection of this single segment can be a valuable lung-preserving procedure in carefully selected patients with tumors located at the border of the upper division and lingular segments. We present here the anatomic and surgical features required for a methodologic left S4 segmentectomy based on our experience and the literature.

Comparison of stapler and electrocautery for division of the intersegmental plane in lung segmentectomy.

BACKGROUND: We retrospectively compared the use of a stapler and electrocautery for division of the intersegmental plane during pulmonary segmentectomy. METHODS: We enrolled 156 patients who underwent pulmonary segmentectomy in our department between March 2006 and August 2020. The patients were divided into electrocautery (n=62) and stapler (n=94) groups based on the device used to divide the intersegmental plane. Patient characteristics, perioperative outcomes, and ratios of actual (calculated using software) to predicted (calculated by counting the resected segments) lung volumes were compared between the two groups. Additionally, we used multivariate analysis to identify the factors that contributed to the incidence of postoperative air leakage after cut-off value was set by receiver operating characteristic (ROC) curve analysis. Moreover, a subset analysis was performed based on the type of segmentectomy (common or uncommon). Common segmentectomies included resection of the basilar or superior segment of the lower lobe, or lingular or upper division of the left upper lobe; all other segmentectomies were classified as uncommon. RESULTS: Compared to the electrocautery group, the stapler group had shorter operative times (P=0.0027), duration of postoperative drainage (P=0.00037), and duration of postoperative hospitalization (P=0.0021). Moreover, incidence of postoperative ≥3 days drainage was significantly reduced in the stapler group (P=0.003). There were no significant differences between the stapler and electrocautery groups in the actual:predicted lung volumes at 6 months (1.01 and 1.04, respectively; P=0.28) or 12 months (1.06 and 1.07, respectively; P=0.68) after surgery. Preoperative lung volume was significantly correlated with preoperative vital capacity (VC) (γ=0.69; P<0.001) and forced expiratory volume in 1 second (FEV1) (γ=0.48; P<0.001). The multivariate analysis indicated that the use of stapler for division of intersegmental plane was the only factor that contributed to reducing the incidence of postoperative ≥3 days drainage (P=0.0027, odds ratio: 0.23, 95% CI: 0.086-0.597). In a subset analysis of uncommon segmentectomy, there were no significant differences among the groups in most perioperative results. CONCLUSIONS: Compared to electrocautery, the use of a stapler for division of the intersegmental plane was associated with better perioperative outcomes, especially reduction of postoperative drainage time, and similar postoperative remnant lung volumes and function.