Diagnostic method of mass spectrometry for detecting lymph node metastasis of non-small cell lung cancer.

BACKGROUND: Histopathology by pathologists is essential in the diagnosis of non-small cell lung cancer (NSCLC). However, auxiliary diagnostic procedures for malignant tumor have continued to evolve. Despite the poor prognosis of patients with NSCLC, the application of the latest procedures and technologies to the field of lung cancer has lagged. Mass spectrometry was used to detect trace amounts of peptides in human tissue with high accuracy. The aim of this study was to establish a method for diagnostic mass spectrometry to identify lymph node metastasis by detecting cytokeratin (CK)19, a useful biomarker in lung cancer. METHODS: We collected 81 lymph nodes with positive expression of CK19 in patients who underwent radical surgical resection in the Department of Thoracic Surgery at Iwate Medical University between May 2020 and December 2022. An X500R instrument was used for sample analysis. A positive result for lymph node metastasis as the detection at least two product ions (FGPGVAFR and ILGATIENSR) from CK19 was defined. RESULTS: Our study indicated a high diagnostic efficiency for mass spectrometry, with 87.5% sensitivity and 91.2% specificity. The mutual concordance of mass spectrometry methods and histopathological diagnosis was 90.1%. CONCLUSIONS: Mass spectrometry offers high diagnostic accuracy and can be clinically applied to auxiliary diagnostic procedures for lymph node metastasis from NSCLC.

Optimal period of smoking cessation to reduce the incidence of postoperative pulmonary complications in lung cancer.

OBJECTIVES: Postoperative pulmonary complications (PPCs) provoke an extended hospital stay and increased postoperative mortality. Although several factors can cause PPCs, smoking is the only factor that can be adjusted within a short period of time preoperatively. However, the optimal period of smoking cessation to reduce the risk of PPCs remains unclear. METHODS: A total of 1260 patients with primary lung cancer who underwent radical pulmonary resection between January 2010 and December 2021 were analysed retrospectively. RESULTS: We classified patients into 2 groups: non-smokers (patients who had never smoked) and smokers (patients who had ever smoked). The frequency of PPCs was 3.3% in non-smokers and 9.7% in smokers. PPCs were significantly less frequent in non-smokers than in smokers (P < 0.001). When smokers were classified according to the duration of smoking cessation, the frequency of PPCs was significantly lower for a duration of 6 weeks or more than for <6 weeks (P < 0.001). In a propensity score analysis performed for 6 or >6 and <6 weeks' smoking cessation in smokers, the frequency of PPCs was significantly lower for smokers with 6 or more weeks' smoking cessation than for smokers with <6 weeks' smoking cessation (P = 0.002). A multivariable analysis identified <6 weeks' smoking cessation as a significant predictor of PPCs for smokers (odds ratio: 4.55, P < 0.001). CONCLUSIONS: Smoking cessation for 6 or more weeks preoperatively significantly reduced the frequency of PPCs.

Surgical treatment for lung metastasis of inflammatory myofibroblastic tumor of the lung: A case report.

Inflammatory myofibroblastic tumor (IMT) is a rare disease that is considered an intermediate neoplasm, with the risk of recurrence and metastasis. Surgical treatment is the standard therapy for IMT, although there are only a few reports of surgery for lung metastasis of pulmonary IMT. We opine that surgical treatment might be effective not only for localized tumors, but also for cases of lung metastasis of IMT.

Evaluation of pulmonary artery bleeding during thoracoscopic pulmonary resection for lung cancer.

BACKGROUND: Bleeding from the pulmonary artery (PA) can be fatal in video-assisted thoracoscopic surgery (VATS) for lung cancer. We evaluated intraoperative PA injury and assessed precautions for thoracoscopic anatomic pulmonary resection. METHODS: We retrospectively analyzed a total of 1098 patients who underwent radical surgery for lung cancer utilizing complete VATS from January 2010 to December 2021. RESULTS: A total of 16 patients (1.5%) had PA injury during VATS, while hemostasis was performed by conversion to thoracotomy in eight patients (50.0%). Although there was a significantly greater operation time and blood loss for patients in the PA injury group (318.4 vs. 264.9 min, p = 0.001; 550.3 vs. 60.5 g, p ≤ 0.001, respectively), there was no significant different for the chest tube insertion duration and length of postoperative hospital stay (4.9 vs. 7.8 days, p = 0.157; 10.6 vs. 9.9 days, p = 0.136, respectively). There was a significant difference observed for the surgical procedure related to the left upper lobectomy in the PA injury group (43.8 vs. 18.8%, p = 0.012), with the primary causative PA determined to be the left anterior segmental PA (A3 ) (31.3%). CONCLUSIONS: VATS is both feasible and safe for lung cancer treatment provided the surgeon performs appropriate hemostasis, although fatal vascular injury could potentially occur during VATS. Surgeons need to be aware of the pitfalls regarding PA dissection management.

No-drain management after thoracoscopic lung wedge resection with a novel intraoperative sealing test.

OBJECTIVE: Although previous studies have reported the safety of no-drain management after thoracoscopic wedge resection, most of those studies were non-inferiority trials. The aim of this study was to evaluate whether no-drain management with an optimal sealing test affects post-operative complications in patients after thoracoscopic wedge resection. METHODS: A total of 906 patients who underwent thoracoscopic lung wedge resection for various disorders except secondary pneumothorax between 2011 and 2020 were analyzed. According to intraoperative findings from the sealing test, patients were divided into groups with chest drain placement (Drain group, n = 514) or no-drain management (no-drain group, n = 392). Our intraoperative sealing test used a flexible drain (Blake®, 19-Fr; Ethicon, Somerville, NJ) connected to the chest drain bag (- 10 cmH2O) to monitor intrathoracic pressure and detect occult alveolar air leakage. Propensity score matching was conducted to balance baseline characteristics of the two groups and reduce selection bias. RESULTS: A total of 250 pairs were matched and standardized differences suggested proper matching had been achieved. Mean length of post-operative hospital stay (4.6 days vs. 3.2 days, p < 0.001) was significantly lower in the no-drain group. Total post-operative complication rates were significantly lower in the no-drain group (6.4% vs. 2.4%, p = 0.03). CONCLUSIONS: No-drain management after thoracoscopic wedge resection was associated with fewer post-operative complications and shorter hospital stay in selected patients. Our novel intraoperative sealing test may be useful for no-drain management of select patients.

Utility of mass spectrometry and artificial intelligence for differentiating primary lung adenocarcinoma and colorectal metastatic pulmonary tumor.

BACKGROUND: Rapid intraoperative diagnosis for unconfirmed pulmonary tumor is extremely important for determining the optimal surgical procedure (lobectomy or sublobar resection). Attempts to diagnose malignant tumors using mass spectrometry (MS) have recently been described. This study evaluated the usefulness of MS and artificial intelligence (AI) for differentiating primary lung adenocarcinoma (PLAC) and colorectal metastatic pulmonary tumor. METHODS: Pulmonary samples from 40 patients who underwent pulmonary resection for PLAC (20 tumors, 20 normal lungs) or pulmonary metastases originating from colorectal metastatic pulmonary tumor (CRMPT) (20 tumors, 20 normal lungs) were collected and analyzed retrospectively by probe electrospray ionization-MS. AI using random forest (RF) algorithms was employed to evaluate the accuracy of each combination. RESULTS: The accuracy of the machine learning algorithm applied using RF to distinguish malignant tumor (PLAC or CRMPT) from normal lung was 100%. The algorithms offered 97.2% accuracy in differentiating PLAC and CRMPT. CONCLUSIONS: MS combined with an AI system demonstrated high accuracy not only for differentiating cancer from normal tissue, but also for differentiating between PLAC and CRMPT with a short working time. This method shows potential for application as a support tool facilitating rapid intraoperative diagnosis to determine the surgical procedure for pulmonary resection.

Validation of completion lobectomy after wedge resection for ≤20 mm non-small cell lung cancer.

BACKGROUND: Completion lobectomy after wedge resection is occasionally performed when final histopathology shows an unexpected primary lung cancer even though the primary lesion has already been resected. The objective of this study was to assess the necessity of completion lobectomy after wedge resection for ≤20 mm non-small cell lung cancer (NSCLC). METHODS: Between 2006 and 2016, a total of 112 patients with NSCLC underwent wedge resection in our department. After exclusions, 40 patients were analyzed. Of these, 17 patients underwent completion lobectomy and 23 patients underwent wedge resection alone. Age, sex, tumor size, histology, other malignant diseases and final surgical procedure were used as prognostic variables. Survival analyses were confirmed using the Kaplan-Meier method and log-rank test. RESULTS: Median follow-up was 70.4 months. No significant difference in 5-year overall survival (OS) and relapse-free survival (RFS) were seen in patients who underwent wedge resection alone compared to the completion lobectomy group (OS: 72.6% vs. 62.5%, P=0.34; RFS: 64.2% vs. 50.0%, P=0.35). Multivariate analysis identified age (>65 years old) and male sex as independent prognostic factors for OS and RFS. CONCLUSIONS: Completion lobectomy after wedge resection did not impact OS or RFS compared with wedge resection alone in patients with ≤20 mm NSCLC. These findings suggested that selected patients may not require resection of the remaining lobe or lymph node dissection after initial wedge resection.

Low-grade fibromyxoid sarcoma arising from the lung: A case report.

Low-grade fibromyxoid sarcoma (LGFMS) is a rare sarcoma subtype that most commonly arises in young adults. This tumor typically presents in the deep soft tissues of the proximal extremities or trunk as a painless mass. Although the most common site of LGFMS metastasis is the lung, it is rarely the primary site. Here, we report a case of primary pulmonary LGFMS. A 22-year-old asymptomatic man was referred to our hospital for investigation of a lung mass that had been discovered incidentally. Computed tomography (CT) showed a well-defined mass 4.0 cm in diameter in the upper lobe of the right lung. Malignancy was suggested by focal uptake of 18F-fluorodeoxyglucose positron-emission tomography (18-FDG-PET). Following surgery, postoperative histological analysis of the resected specimen demonstrated LGFMS based on histological and immunohistological findings. In particular, mucin 4 showed diffuse positivity in the spindle-shaped tumor cells. In conclusion, LGFMS can arise in the lungs, and physicians should consider this entity as a differential diagnosis for solitary lung mass in young adults.

Correlation with spontaneous pneumothorax and weather change, especially warm front approaching.

BACKGROUND: Primary spontaneous pneumothorax (PSP) occurs more frequently in young, tall men, with approximately 10,000 times video-assisted thoracoscopic surgery (VATS) annually in Japan is undergoing for surgical treatment. The underlying mechanisms remain unclear, but several reports have suggested correlation with weather conditions. This study aimed to evaluate the relationship between onset of PSP and changes in weather. METHODS: We retrospectively analyzed data from 112 patients who underwent VATS for PSP in Iwate, Japan from 1 January 2010 to 14 June 2020. Of the 3,818 days in this study period, the day on which the patient became aware of symptoms was classified as the PSP onset day (n=112), and all others were classified as PSP non-onset day (n=3,706). Meteorological data were collected from airbase station using an online source for the same place and same time. Logistic regression modeling was used to obtain predicted risks for the onset of PSP with respect to weather conditions. RESULTS: Among the meteorological parameters, significant differences were mainly found at 2 days before onset for increasing average temperature [odds ratio (OR): 1.97, P=0.018], minimum temperature (OR: 1.97, P=0.018), average humidity (OR: 1.58, P=0.043), and decreased the sunshine time (OR: 2.26, P=0.012). No significant difference was observed in atrophic pressure at 2 days before onset. CONCLUSIONS: Onset of PSP may correlate with the increased temperature and humidity, seen with an approaching of warm front.

Utility of the powered stapler for radical pulmonary resection: a propensity score-matched analysis.

PURPOSE: Anatomical pulmonary resection, such as lobectomy, is a common procedure. Staplers play an important role in dividing an incomplete interlobular fissure, especially in thoracoscopic surgery. This study evaluates the effectiveness of a powered stapler for reducing the need for intraoperative fibrin glue and the incidence of air leakage after radical pulmonary resection. METHODS: The subjects of this retrospective study were 478 patients who underwent radical pulmonary resection. Propensity score analysis generated two matched pairs of 177 patients treated using powered and manual staplers, respectively. RESULTS: The need for fibrin glue intraoperatively during radical pulmonary resection was significantly less in the powered-stapler group (47.5%) than in the manual-stapler group (58.8%, p = 0.033). The incidence of postoperative air leakage following radical pulmonary resection was also significantly lower in the powered-stapler group (2.8%) than in the manual-stapler group (10.7%, p = 0.003). Logistic regression analysis identified use of the powered stapler as a factor independently associated with both non-use of fibrin glue intraoperatively (odds ratio, 0.63; p = 0.040) and no postoperative air leakage (odds ratio, 0.26; p = 0.010). CONCLUSION: Using a powered stapler to divide the incomplete interlobular fissure decreased the need for additional intraoperative management using fibrin glue and reduced postoperative air leakage in radical pulmonary resection.

Prediction formula for predicted diffusion capacity of lung for carbon monoxide in pulmonary surgery.

OBJECTIVES: Diffusion capacity of the lung for carbon monoxide (DLCO) is a useful value for perioperative risk assessment of non-small cell lung cancer (NSCLC). The percentage of the predicted DLCO (%DLCO: DLCO/predicted DLCO × 100) is often evaluated by setting cutoff values as in the clinical field, but several formulae are available for calculating the predicted DLCO, and the %DLCO thus varies depending on the formula used to predict DLCO. We examined differences in %DLCO calculated using several commonly used prediction formulae. METHODS: A total of 490 eligible patients who underwent completed video-assisted thoracoscopic surgery (c-VATS), especially radical pulmonary lobectomy, for NSCLC were analyzed retrospectively. Predicted DLCO was calculated using the prediction formulae described by Burrows, Nishida, Cotes, and Kanagami, then the relationships with postoperative complications were evaluated. RESULTS: The %DLCO from Nishida's formula was two-thirds the value of that from Burrows' (p < 0.05). On logistic regression analysis, predicted postoperative %DLCO (ppo-DLCO) based on the formulae of Burrows, Cotes and Kanagami were independent factors related to postoperative pulmonary complications after c-VATS lobectomy for NSCLC (odds ratios 2.46, 1.79 and 2.33, p = 0.005, 0.043 and 0.009, respectively). CONCLUSIONS: The %DLCO is a useful index for surgical risk assessment of c-VATS lobectomy for NSCLC, while the results differ markedly between individual prediction formulae. Specification of the formula used is necessary in cases considering risk evaluations.

Reduction of air leakage using linear staple device with bioabsorbable polyglycolic acid felt for pulmonary lobectomy.

OBJECTIVE: Pulmonary fistula is a common complication in pulmonary lobectomy for non-small cell lung cancer (NSCLC). Although a linear staple device with bioabsorbable polyglycolic acid (PGA) is used for pulmonary wedge resection with fragile pulmonary parenchyma, the efficacy of the stapler with PGA for dividing incomplete interlobular fissure in pulmonary lobectomy has not been elucidated. This study aimed to evaluate the usefulness of the stapler with PGA in reducing postoperative air leakage when dividing incomplete interlobular fissure in pulmonary lobectomy for NSCLC. METHODS: A total of 546 patients who underwent radical lobectomy for NSCLC were analyzed retrospectively. Propensity score analysis generated two matched pairs of 125 patients in both stapler and stapler with PGA groups. RESULTS: After propensity score matching, postoperative air leakage following pulmonary lobectomy was significantly less frequent in the stapler with PGA group (9.6%) than in the stapler group (22.4%, p = 0.006). Intraoperative additional management of PGA and/or fibrin glue was decreased in the stapler with PGA group (56.0% vs. 70.4%, p = 0.018, 54.4% vs. 69.6%, p = 0.013, respectively). On logistic regression analysis, stapler with PGA was an independent factor for preventing postoperative air leakage (odds ratio, 0.38; p = 0.015). CONCLUSIONS: Using the stapler with PGA to divide the incomplete interlobular fissure in pulmonary lobectomy reduced postoperative air leakage, and decreased the need for additional intraoperative management using fibrin glue.

Influence of prophylactic antibiotic duration on postoperative pneumonia following pulmonary lobectomy for non-small cell lung cancer.

BACKGROUND: Although postoperative pneumonia after radical surgery for non-small cell lung cancer (NSCLC) carries a mortality risk, the duration of postoperative prophylactic antibiotics against pneumonia has not been elucidated. This study aimed to evaluate the influence of the duration of prophylactic antibiotics on postoperative pneumonia following radical surgery for NSCLC in patients who received antibiotics intraoperatively (short period) and in those who received antibiotics both intraoperatively and postoperatively (long period). METHODS: A total of 477 patients who underwent radical lobectomy for NSCLC were analyzed retrospectively. Propensity score analysis generated two matched pairs of 152 patients in both the short and long period groups. RESULTS: After propensity score matching, the incidence of postoperative pneumonia following pulmonary lobectomy was significantly less in the long period group than in the short period group (3.9% vs. 16.4%, P<0.001). On logistic regression analysis, short period of prophylactic antibiotic administration was the independent risk factor for postoperative pneumonia (odds ratio: 6.82, P<0.001). CONCLUSIONS: Prophylactic antibiotic administration in both the intraoperative and postoperative periods reduced the incidence of pneumonia after pulmonary lobectomy for NSCLC.

The utility of the Stapler with PGA sheet for pulmonary wedge resection: a propensity score-matched analysis.

BACKGROUND: Air leakage is a common complication after pulmonary wedge resection. The aim of this study was to evaluate the effect of staple line reinforcement in reducing air leakage after pulmonary wedge resection. METHODS: A retrospective analysis was performed on patients who underwent pulmonary wedge resection. The patients were classified into 2 groups; the Stapler with polyglycolic acid sheet was used for the reinforced and the Stapler without polyglycolic acid sheet was used for the non-reinforced group. The patients were matched one-to-one based on a propensity score that comprised several patient characteristics. A propensity score-matched analysis was performed to compare patient outcomes. RESULTS: A total of 291 patients who met the inclusion criteria were investigated. There were 165 in the reinforced group and 126 patients in the non-reinforced group. Propensity score analysis generated 104 matched pairs of patients in both the reinforced and the non-reinforced groups. The rate of non-placement of chest tube was significantly higher in the reinforced group than in the non-reinforced group (61.5% vs. 36.5%; P<0.001). The rate of postoperative air leakage was higher in the non-reinforced group than in the reinforced group (13.5% vs. 1.9%, P<0.001). On logistic regression analysis, not using the reinforcement device was one of the independent factors related to pulmonary air leakage after pulmonary wedge resection (OR: 8.58, P<0.001). CONCLUSIONS: The use of the Stapler with polyglycolic acid sheet during pulmonary wedge resection increased the rate of intraoperative chest tube removal and reduced the rate of postoperative air leakage.

Usefulness of a suction ball coagulation probe for hemostasis in complete VATS lobectomy for patients with non-small cell lung cancer.

PURPOSE: In recent years, several reports have noted that the specific coagulation mode called "soft coagulation" with modern electrosurgical tools offers superior hemostasis. The "suction ball coagulation" (SBC) device, which can achieve hemostasis using a soft coagulation mode and simultaneous suction, has been developed as a next step. This study aimed to evaluate the hemostatic effects of SBC in comparison to a conventional soft coagulation device (non-SBC) in video-assisted thoracoscopic surgery (VATS) for patients with non-small cell lung cancer (NSCLC). METHODS: This study retrospectively analyzed 351 patients who underwent complete VATS lobectomy for NSCLC. A propensity score analysis generated matched pairs from the patients in the SBC and non-SBC groups (119 patients each). RESULTS: After propensity score matching, the bleeding volume during surgery in the SBC group (27.0 g) was significantly less than that in the non-SBC group (42.0 g, p < 0.001). No significant difference was seen in the frequency of postoperative complications. A logistic regression analysis identified the non-use of SBC as an independent risk factor for greater intraoperative blood loss during complete VATS lobectomy (odds ratio 3.14, p < 0.001). CONCLUSIONS: SBC was safe for complete VATS lobectomy in patients with NSCLC, and the use of this device was associated with significantly decreased intraoperative blood loss.