A case of concurrent follicular lymphoma and lung cancer requiring differentiation from lymph node metastasis.

Lung cancer complicated by follicular lymphoma has rarely been reported in the literature. A 69-year-old male with an abnormal shadow on a chest radiograph was referred to our hospital. A mass in the right lung was seen on chest computed tomography (CT). Positron emission tomography-CT showed fluorodeoxyglucose accumulation in the esophagus and multiple intra-abdominal lymph nodes, in addition to the right lung lesion. The lung lesion was diagnosed as a pulmonary adenocarcinoma after biopsy. Upper and lower gastrointestinal endoscopies did not reveal the presence of a tumor. Open lymph node biopsy was performed to determine the course of treatment, leading to a diagnosis of follicular lymphoma. The patient finally underwent radical resection for lung cancer; the follicular lymphoma was judged to be low-grade and was followed up. When complications involving other organs are detected during systemic examination of a patient with lung cancer, it is necessary to distinguish between metastasis to other organs and complications of other malignant diseases, as this will greatly influence the treatment strategy.

Vacuum-assisted closure for chest wall reconstruction infection caused by Streptococcus mitis after surgery of lung cancer: a case report.

BACKGROUND: Among a cohort of patients who underwent chest wall resection and reconstruction by rigid prosthesis, 6% required removal of the prosthesis, and in 80% of these cases the indication for prosthesis removal was infection. Although artificial prosthesis removal is the primary approach in such cases of infection, the usefulness of vacuum-assisted closure (VAC) has also been reported. CASE PRESENTATION: A 64-year-old man with diabetes mellitus underwent right middle and lower lobectomy with chest wall (3rd to 5th rib) resection and lymph node dissection because of lung squamous cell carcinoma. The chest wall defect was reconstructed by an expanded polytetrafluoroethylene (PTFE) sheet. Three months after surgery, the patient developed an abscess in the chest wall around the PTFE sheet. We performed debridement and switched to VAC therapy 2 weeks after starting continuous drainage of the abscess in the chest wall. The space around the PTFE sheet gradually decreased, and formation of wound granulation progressed. We performed wound closure 6 weeks after starting VAC therapy, and the patient was discharged 67 days after hospitalization. CONCLUSIONS: We experienced a case of chest wall reconstruction infection after surgery for non-small cell lung cancer that was successfully treated by VAC therapy without removal of the prosthesis. Although removal of an infectious artificial prosthesis can be avoided by application of VAC therapy, perioperative management to prevent surgical site infection is considered essential.

Successful surgical treatment of an intraoperatively ruptured lung abscess rupture using free pericardial fat implantation: a case report.

BACKGROUND: Lung abscess treatment results the treatment results improved with the development of antibiotics; however, surgical treatment is indicated when pyothorax is present, surgical treatment is indicated. When a lung abscess ruptures, pyothorax and fistula occur, which are difficult to treat. CASE PRESENTATION: A 74-year-old woman who experienced exacerbated dyspnea and left back pain for 10 days was diagnosed with a lung abscess caused by an odontogenic infection. The patient's medical history included hypertension, angina pectoris, untreated dental caries, and periodontitis. Despite administration of meropenem for 5 days, inflammatory markers increased. Chest radiography revealed pleural effusion exacerbation; therefore, the patient immediately underwent chest drainage and surgery was planned. Thoracic debridement and parietal and visceral decortication were performed. However, the lung abscess in the lateral basal segment ruptured during visceral decortication. As the tissue was fragile and difficult to close with sutures, free pericardial fat was implanted in the ruptured abscess cavity and fixed with fibrin glue, and sutured to the abscess wall. No signs of postoperative air leakage or infection of the implanted pericardial fat were observed. All drainage tubes were removed by postoperative day 9. The patient was discharged on postoperative day 12 and underwent careful observation during follow-up as an outpatient. At 1 year and 2 months after surgery, empyema recurrence was not observed. CONCLUSIONS: A lung abscess that ruptured intraoperatively was successfully and effectively treated by implantation of free pericardial fat in the abscess cavity.

Prognostic factors among patients with resected non-adenocarcinoma of the lung.

INTRODUCTION: Few studies have investigated the prognostic factors for non-adenocarcinoma of the lung. We retrospectively evaluated the prognostic factors on the basis of histological type of non-adenocarcinoma of the lung treated by pulmonary resection. METHODS: We enrolled 266 patients with non-adenocarcinoma of the lung in this retrospective study: 196 with squamous cell carcinoma (SCC) and 70 with non-SCC. RESULTS: Relapse-free survival (RFS) did not differ significantly between SCC and non-SCC patients (P=.33). For SCC patients, RFS differed significantly between patients who underwent wedge resection and non-wedge resection (P<.01), and between patients with Clavien¬-Dindo grade ≥3a and 0-2 postoperative complications (P<.01). For non-SCC patients, RFS rates were significantly different in the groups divided at neutrophil neutrophil-to-lymphocyte ratio =2.40 (P=.02), maximum standardized uptake value (SUVmax)=8.39 (P<.01), between patients with pathological stage (pStage) 0-I and with pathological stage more than II (P<.01). For SCC patients, male sex (P=.04), wedge resection (P=.01), and Clavien-Dindo grade ≥3a (P=.02) were significant factors for RFS in multivariate analysis. For non-SCC patients, neutrophil-to-lymphocyte ratio >2.40 (P<.01), SUVmax >8.39 (P=.01), and pStage ≥II (P=.03) were significant factors for RFS in multivariate analysis. CONCLUSION: RFS did not differ significantly differently between SCC and non-SCC patients. It is necessary to perform more than segmentectomy and to avoid severe postoperative complications for SCC patients. SUVmax might be an adaptation criterion of adjuvant chemotherapy for patients with non-adenocarcinoma and non-SCC of the lung.

Bilateral adrenal infarction and insufficiency associated with antiphospholipid syndrome and surgery: a case report.

BACKGROUND: Antiphospholipid syndrome causes systemic arterial and venous thromboses due to the presence of antiphospholipid antibodies. Adrenal insufficiency is a rare complication of antiphospholipid syndrome that may result in fatal outcomes if left untreated. Therefore, we report adrenal insufficiency as a rare complication of bilateral adrenal infarction associated with antiphospholipid syndrome and trauma surgery. CASE PRESENTATION: A 64-year-old male patient underwent surgery for a left traumatic hemothorax. He concurrently had antiphospholipid syndrome and was receiving warfarin. Postoperatively, the patient complained of severe lumbar back pain despite resuming anticoagulation therapy, and he experienced paralytic ileus and shock. Abdominal contrast-enhanced computed tomography revealed adrenal swelling and increased surrounding retroperitoneal adipose tissue density. Diffusion-weighted abdominal magnetic resonance imaging showed high-intensity areas in the bilateral adrenal glands. Cortisol and adrenocorticotropic hormone levels were 3.30 µg/dL and 185.1 pg/dL, respectively. Subsequently, the patient was diagnosed with bilateral adrenal infarction and acute adrenal insufficiency, and hydrocortisone was immediately administered. Adrenal insufficiency improved gradually, and the patient was discharged after initiating steroid replacement therapy. CONCLUSIONS: The timing of postoperative anticoagulant therapy initiation remains controversial. Therefore, adrenal insufficiency due to adrenal infarction should be monitored while anticoagulant therapy is discontinued in patients with antiphospholipid syndrome.

Relative efficacies of EGFR-TKIs and immune checkpoint inhibitors for treatment of recurrent non-small cell lung cancer after surgery.

INTRODUCTION: The relative efficacies of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and immune checkpoint inhibitors (ICIs) for the treatment of recurrent non-small cell lung cancer (NSCLC) after surgery remain unclear. METHODS: Among 801 patients with NSCLC who underwent pulmonary resection at Kanazawa Medical University between 2017 and 2021, 64 patients had recurrence. We retrospectively compared the efficacies of EGFR-TKIs and ICIs in these patients with recurrent NSCLC who underwent pulmonary resection. RESULTS: The 3-year overall survival rates after recurrence were 79.3% in patients who received EGFR-TKIs, 69.5% in patients who received ICIs, and 43.7% in patients who received cytotoxic agents. There was no significant difference in overall survival between patients treated with EGFR-TKIs and ICIs (p=0.14) or between patients treated with ICIs and cytotoxic agents (p=0.23), but overall survival was significantly higher in patients treated with EGFR-TKIs compared with cytotoxic agents (p<0.01) The probabilities of a 2-year response were 88.5%, 61.6%, and 25.9% in patients treated with EGFR-TKIs, ICIs, and cytotoxic agents, respectively. There was no significant difference in response periods between patients treated with EGFR-TKIs and ICIs (p=0.18), but the response period was significantly better in patients treated with EGFR-TKIs (p<0.01) or ICIs (p=0.03) compared with cytotoxic agents. Percent-predicted vital capacity (p=0.03) and epidermal growth factor receptor gene mutation (p<0.01) were significant factors affecting the overall response to chemotherapy in multivariate analysis. CONCLUSION: EGFR-TKIs and ICIs are effective for treating recurrent NSCLC after surgery. Although adjuvant chemotherapy for completely resected pathological stage II to IIIA NSCLC, atezolizumab or Osimertinib, has also been recently approved as adjuvant chemotherapy, there is a risk that patients who relapse after adjuvant chemotherapy will have less choice.

Association between lower lobe location and early recurrence for non-small cell lung cancer.

OBJECTIVES: It is unclear whether a lower lobe origin is a risk factor for early recurrence of non-small cell lung cancer (NSCLC) in patients who underwent pulmonary resection. MATERIALS AND METHODS: The risk factors for early recurrence, defined as recurrence occurring within 1 year after surgery, were analyzed in 476 patients with NSCLC who underwent pulmonary resection without wedge resection. RESULTS: The proportion of men, Brinkman's index, carcinoembryonic antigen levels, and the maximum standardized uptake value (SUVmax) were significantly higher in patients with early recurrence than in those without early recurrence. Furthermore, the rates of lower lobe origin, extended resection beyond lobectomy, lymphatic invasion, vascular invasion, and advanced-stage disease were significantly higher in patients with early recurrence. Age (odds ratio [OR] = 4.46, p < 0.01), SUVmax (OR = 5.78, p = 0.02), a lower lobe origin (OR = 3.06, p = 0.01), and pathological stage (OR = 3.34, p = 0.01) were risk factors for early recurrence in multivariate analysis. Furthermore, only early recurrence (OR = 3.34, p = 0.01) was a risk factor for overall survival in multivariate analysis, and overall survival outcomes and prognoses significantly differed between patients with and without early recurrence (p < 0.01). CONCLUSIONS: Age, SUVmax, a lower lobe origin, and pathological stage are risk factors for early recurrence. These results suggest that for patients with NSCLC who underwent pulmonary resection, SUVmax and a lower lobe origin are important for deciding the indication for adjuvant chemotherapy in addition to pathological stage.

Predictive value of recurrence of solid and micropapillary subtype in lung adenocarcinoma.

INTRODUCTION: Although histological subtype in lung adenocarcinoma has been reported as a poor prognostic factor in several studies, its utility has not yet been revealed as an adaptation criterion of postoperative adjuvant chemotherapy. MATERIALS AND METHODS: Four hundred ninety-four lung adenocarcinoma patients were enrolled in this retrospective study. A sub-analysis was performed in 420 lung adenocarcinoma patients with pathological stage 0-I disease for risk factors of postoperative recurrence. RESULTS: Maximum standardized uptake value (SUVmax) (p<0.01), pathological stage ≥II (p<0.04), and adjuvant chemotherapy (p<0.01) were risk factors for recurrence in the multivariate analysis, whereas histological subtype was not a significant factor for recurrence at all stages. In the sub-analysis, univariate analysis showed that carcinoembryonic antigen expression (p<0.01), prognostic nutrition index (p=0.03), SUVmax (p<0.01), lymphatic invasion (p<0.01), vascular invasion (p<0.01), grade 3-4 differentiation (p<0.01), pathological stage ≥IA3 (p<0.01), and histological subtype (p=0.03) were significant risk factors of recurrence. SUVmax (p<0.01) was the only risk factor for recurrence in the multivariate analysis, whereas histological subtype was not (p=0.07). Relapse-free survival (RFS) was significantly worse in the micropapillary- and solid-predominant subtype groups than in the other subtypes (p=0.01). On the other hand, RFS by with or without uracil-tegafur as adjuvant chemotherapy in lung micropapillary-predominant or solid-predominant adenocarcinoma patients with pathological stage IA-IB disease was not significantly different. CONCLUSION: This study suggested that histological subtypes such as micropapillary- or solid-predominant pattern are risk factors for recurrence in pathological stage 0-I lung adenocarcinoma and may be necessary adjuvant chemotherapy instead of uracil-tegafur.

Prognostic Impact of Cancer Inflammation Prognostic Index for Non-small Cell Lung Cancer.

PURPOSE: Cancer-inflammation prognostic index (CIPI) is calculated by multiplying the concentration of carcinoembryonic antigen by neutrophil-to-lymphocyte ratio. CIPI has been reported as a prognostic factor for colorectal cancer. Although carcinoembryonic antigen and neutrophil-to-lymphocyte ratio have been reported as prognostic factors for non-small cell lung cancer (NSCLC), it has not been investigated whether CIPI is a useful marker. METHODS: We analyzed the prognostic factors, including CIPI, in 700 NSCLC patients treated by pulmonary resection. We also analyzed a subgroup of 482 patients with pathological stage I NSCLC. RESULT: CIPI > 14.59 (P < 0.01), maximum standardized uptake value (SUVmax) > 5.35 (P < 0.01), lymphatic invasion (P = 0.01), and pathological stage (P < 0.01) were significant factors for relapse-free survival (RFS) in multivariate analysis. SUVmax > 5.35 (P < 0.01) and pathological stage (P < 0.01) were revealed as significant factors for overall survival in the multivariate analysis. In the subanalysis, CIPI > 14.88 (P = 0.01) and SUVmax > 5.07 (P < 0.01) were significant factors for RFS of pathological stage I NSCLC in multivariate analysis. CONCLUSION: CIPI was a significant factor for RFS in NSCLC patients treated surgically, even in those with pathological stage I disease. SUVmax was also a significant factor for RFS and overall survival in NSCLC patients treated surgically, and for RFS in patients with pathological stage I NSCLC. TRIAL REGISTRATION: The Institutional Review Board of Kanazawa Medical University approved the protocol of this retrospective study (Approval Number: I392), and written informed consent was obtained from all patients.

Iatrogenic tracheal laceration due to rigid bronchoscopy treated by endoscopic stent placement: a case report.

Although rigid bronchoscopy may lead to tracheal injury, the incidence is unknown. A 59-year-old woman diagnosed with clinical stage IV esophageal cancer was scheduled to undergo placement of a silicon Y-stent by rigid bronchoscopy to address tracheal stenosis. When the tumor was cored out by rigid bronchoscopy, perforation of the lower trachea occurred, and a silicon Y-stent was inserted to cover the tracheal fistula. Chest X-ray revealed right pneumothorax, and chest drainage was performed. When spontaneous ventilation was confirmed, the patient was weaned from the ventilator in the operating room. Chest computed tomography immediately after surgery showed an air space on the right side of the stent. The space gradually disappeared over time, and no air leakage was observed. The chest drain was removed on postoperative Day 12. Conservative treatment using a silicon Y-stent for iatrogenic tracheal injury due to rigid bronchoscopy is safe.

The Utility of SUVmax as an Adaptation Criterion for Limited Resection in Stage IA Non-Small Cell Lung Cancer.

INTRODUCTION: Although the consolidation diameter of a tumor on computed tomography (CT) is an adaptation criterion for limited resection in early-stage non-small cell lung cancer (NSCLC), whether the maximum standardized uptake value (SUVmax) is also an adaptation criterion for limited resection has not been evaluated. METHODS: In total, 478 NSCLC patients with clinical stage IA disease were analyzed, among whom 383 were used to perform a sub-analysis. RESULTS: Multivariate analysis showed that consolidation diameter (odds ratio [OR]: 3.05, p = 0.01), SUVmax (OR: 10.74, p = 0.02), and lymphatic invasion (OR: 10.34, p < 0.01) were risk factors for lymph node metastasis in clinical stage IA NSCLC patients. Furthermore, age (OR: 2.98, p = 0.03), SUVmax (OR: 13.07, p = 0.02), and lymphatic invasion (OR: 5.88, p = 0.02) were risk factors for lymph node metastasis in clinical stage IA lung adenocarcinoma patients according to multivariate analysis. CONCLUSION: Consolidation diameter of a tumor on CT, SUVmax, and lymphatic invasion are risk factors for lymph node metastasis. However, SUVmax was a risk factor for lymph node metastasis rather than consolidation diameter on CT in lung adenocarcinoma patients. These results suggest that for early-stage lung adenocarcinoma patients, SUVmax is more important for deciding the indication of limited resection than consolidation diameter of the tumor on CT.

13019Tension pyopneumothorax caused by Parvimonas micra: a case report.

Tension pyopneumothorax is a rare and life-threatening complication of pneumonia, lung abscess, and empyema, and immediate thoracic drainage or surgery is required. A 70-year-old man presented to another hospital 2 weeks after exacerbation of dyspnea and anorexia. Chest X-ray imaging revealed leftward deviation of the mediastinum, pleural effusion, and collapse of the right lung. The patient was referred to our hospital for surgical treatment. He underwent chest drainage immediately after the transfer. The patient's blood pressure was elevated after drainage. Chest X-ray imaging showed improvement in the mediastinal deviation, but expansion failure of the lung occurred. Debridement and parietal and visceral decortications were performed under thoracotomy. The thoracic cavity was irrigated using a pulse lavage irrigation system with 12,000 mL of saline. The patient underwent fibrinolytic therapy with intrathoracic urokinase postoperatively because of persistent high inflammatory marker levels and multilocular pleural effusion. Parvimonas micra was detected in the preoperative pleural fluid culture. He was discharged on postoperative day 22 and followed up as an outpatient afterwards. Two years have passed since the surgery, and there has been no recurrence of empyema. Decortication of the parietal and visceral pleura and irrigation using a pulse lavage irrigation system were effective.

Impacts of perioperative hyponatremia relevant to outcomes and prognosis of non-small cell lung cancer in octogenarians.

BACKGROUND: A recent study reported the effect of preoperative hyponatremia on postoperative outcomes of patients with non-small cell lung cancer. However, the influence of postoperative hyponatremia on postoperative outcomes has not been completely investigated. METHODS: We retrospectively studied 75 octogenarians who underwent pulmonary surgery for non-small cell lung cancer between 2009 and 2018. We divided them into hyponatremic and non-hyponatremic groups, depending on preoperative and immediate postoperative serum sodium levels, and investigated their clinicopathological characteristics and outcomes. Disease-specific survival and cumulative incidence of relapse rates between the two groups were calculated and compared using the stratified Kaplan-Meier method. Univariable and multivariable analyses were performed to identify prognostic factors. RESULTS: Preoperative hyponatremia was associated with 66.7% of postoperative respiratory and 88.9% of non-cardiovascular complications. The long-term prognosis of the postoperative hyponatremic group was significantly worse than that of their counterpart. The 3-year disease-specific survival and 3-year cumulative incidence of relapse rate were 55.9% and 46.2%, respectively, and the median observation period after surgery was 37.4 (interquartile range, 23.7-51.0) months for the entire cohort. Kaplan-Meier curves showed that hyponatremia was associated with worse disease-specific survival and cumulative incidence of relapse. Multivariable analysis identified hyponatremia as a factor that predicted unfavorable disease-specific survival and cumulative incidence of relapse. CONCLUSIONS: Immediate postoperative hyponatremia is an independent predictor of non-small cell lung cancer outcomes among octogenarians. Preoperative hyponatremia was associated with a high frequency of postoperative respiratory and non-cardiovascular complications. Surgical indications in older patients with hyponatremia should be carefully considered with follow-up.

Temporary tracheotomy for post-intubation laryngeal edema after lung cancer surgery: a case report.

BACKGROUND: In the post-intubation period, laryngeal edema is one of the most severe complications, which can cause significant morbidity and even death. Herein, we report a case in which we performed a temporary tracheostomy during surgery because of the risk of postoperative laryngeal edema, successfully avoiding post-intubation laryngeal edema complications. CASE PRESENTATION: A 78-year-old man underwent surgery for left upper lobe lung cancer. He had a history of chemoradiotherapy for laryngeal cancer, bronchial asthma, and chronic obstructive pulmonary disease. He was diagnosed with grade 1 laryngeal edema using computed tomography, and there was a risk of developing post-intubation laryngeal edema. Additionally, there was a decrease in laryngeal and pulmonary functions; therefore, postoperative aspiration pneumonia was judged to be a fatal risk. A temporary tracheostomy was performed during surgery to avoid postoperative intubation laryngeal edema. He was found to have exacerbated laryngeal edema, which is a serious complication of airway stenosis. CONCLUSIONS: Temporary tracheostomy should be considered to avoid airway stenosis due to post-intubation laryngeal edema in patients with laryngeal edema after radiotherapy.

[Pulmonary Nodule Localization by Pleural Marking Using Virtual Thoracoscopic Imaging].

Percutaneous or transbronchial markings are performed to localize pulmonary nodules preoperatively. We present a novel intraoperative procedure that utilizes virtual thoracoscopic imaging-assisted pleural marking. In this procedure, a virtual thoracoscopic image is created preoperatively, and the coordinates of the pleural point above the tumor are determined. The pleural marker is intraoperatively placed on the coordinates, and dye is transferred to the visceral pleura with two lung ventilations. We present the specific procedures and countermeasures for cases when nodules are not palpable. Additionally, we present a comparison between the various methods of preoperative marking and this method.

Improvements in perioperative outcomes for non-small cell lung cancer: a decade-long analysis.

BACKGROUND: Video-assisted thoracic surgery (VATS) procedures for non-small cell lung cancer (NSCLC) have steadily increased and have become the gold standard, but their prognostic advantage compared with thoracotomy has not been elucidated. This study retrospectively evaluated perioperative characteristics of VATS for NSCLC over time. METHODS: We collected the clinical data of 760 patients with NSCLC who underwent pulmonary resection over the past decade, classifying patients into early (2011-2015) and late (2016-2020) periods. Changes in NSCLC patient characteristics, surgical approaches, perioperative factors, postoperative morbidities, and prognoses were analyzed. RESULTS: Patients in the late period were older (p = 0.01), had more comorbidities (p = 0.01), and had earlier-stage cancer (p < 0.01) than those in the early period. The late period had significantly fewer surgical procedures for lobectomy or extended resection beyond lobectomy (p < 0.01), open thoracotomies (p < 0.01), postoperative (p = 0.02) and severe morbidities (p < 0.01), and a significantly shorter postoperative hospital stay than the early period. Surgical procedures of lobectomy or extended resection beyond lobectomy (p < 0.01) were significant risk factors for postoperative morbidity, and being in the early period (p < 0.01) and surgical procedures of lobectomy or extended resection beyond lobectomy (p < 0.01) were significant risk factors for severe postoperative morbidities. The overall survival prognosis significantly differed between the groups (p = 0.02) but progression-free survival did not (p = 0.89). CONCLUSIONS: The incidence of postoperative morbidities decreased over time in older patients and patients with more comorbidities. The prognosis of patients with NSCLC did not change with increasing VATS or sublobar resection.

PD-L1 Expression is not a Predictive Factor for Recurrence in Resected Non-small Cell Lung Cancer.

PURPOSE: Although targeting programmed death-1 (PD-1) and its ligand, programmed death-ligand 1 (PD-L1), is an established treatment modality for non-small cell lung cancer (NSCLC), the prognostic relevance of PD-L1 expression in NSCLC patients who undergo pulmonary resection is controversial. METHODS: Two hundred thirty-seven NSCLC patients who underwent pulmonary resection were enrolled and the relationship between PD-L1 and various clinicopathological factors, as well as the prognostic relevance of PD-L1, was evaluated. RESULTS: PD-L1 expression was significantly higher in male patients (p < 0.01), lymphatic invasion (p < 0.01), vascular invasion (p < 0.01), grade 3-4 differentiation (p < 0.01), squamous cell carcinoma (p < 0.01), and pathological stage > II (p < 0.01), but significantly lower in those who were epithelial growth factor receptor (EGFR) mutation negative (p < 0.01). Relapse-free survival was significantly worse in patients with PD-L1 expression (p = 0.04). Univariate analysis showed that male sex (p = 0.04), carcinoembryonic antigen expression (CEA) (p < 0.01), maximum standardized uptake value (p < 0.01), lymphatic invasion (p < 0.01), vascular invasion (p < 0.01), grade 3-4 differentiation (p < 0.01), lower lobe disease (p = 0.04), PD-L1 expression (p = 0.03), and pathological stage (p < 0.01) were significant risk factors of recurrence. In multivariate analysis, CEA expression (p = 0.01), lymphatic invasion (p = 0.04), and pathological stage (p < 0.01) were risk factors for recurrence, whereas PD-L1 expression was not a significant factor of recurrence (p = 0.62). CONCLUSION: PD-L1 expression was not a risk factor of recurrence but tumor progression tended to increase PD-L1 expression. TRIAL REGISTRATION: The Institutional Review Board of Kanazawa Medical University approved the protocol of this retrospective study (approval number: I392), and written informed consent was obtained from all patients.

Adhesion is a risk factor for postoperative recurrence of spontaneous pneumothorax.

Background: Several risk factors for postoperative recurrence of spontaneous pneumothorax have been reported, but the identified risk factors differed among studies. Methods: A total of 183 primary spontaneous pneumothorax patients were enrolled in this retrospective study, and the risk factors for postoperative recurrence were evaluated. Results: Among the patients, more than 80% with ipsilateral postoperative recurrence (IPR) relapsed within 3 years and more than 80% with contralateral postoperative recurrence relapsed within 4 years. Compared with patients without IPR, patients with IPR had significantly more cases with history of pneumothorax (P<0.10), more cases without preoperative drainage (P=0.02), more cases with intraoperative adhesion (P<0.01), greater upward lung volume (P=0.04), more numbers of automatic sutures (P=0.04), and more cases with contralateral recurrence (P<0.01). Furthermore, compared with patients without adhesion, patients with adhesion had significantly older age (P<0.01), and more cases with adhesion on CT images (P<0.01). Patients with adhesion also had significantly greater upward lung volume (P<0.01), more cases that received covering with polyglycolic acid (PGA) sheet covering with fibrin glue (P=0.01), and more cases that received re-do surgery (P=0.04). IPR was significantly more common in the adhesion group (P<0.01), while contralateral postoperative recurrence did not differ significantly between the groups with and without adhesion (P=0.06). Univariate analyses showed that body mass index (BMI) <15.6 kg/m2 (P<0.01), history of pneumothorax (P=0.01), intraoperative adhesion (P<0.01), upward lung volume >80% (P=0.02), lateral lung volume >80% (P=0.02), 3 fire or more of automatic sutures (P=0.03), and contralateral recurrence (P=0.01) were significant risk factors for IPR. BMI <15.6 kg/m2 (odds ratio: 20.89; 95% confidence interval: 1.55-280.70; P=0.02) and intraoperative adhesion (odds ratio: 25.58; 95% confidence interval: 1.91-342.39; P=0.01) were identified as risk factors for IPR in a multivariate analysis. Conclusions: The present findings suggest that low BMI and intraoperative adhesion are risk factors for postoperative recurrence of spontaneous pneumothorax. For such patients, additional intraoperative procedures, such as covering with PGA sheet absorbable oxidized cellulose may be required to reduce postoperative recurrence.