Prolonged air leak (PAL) is one of the most common complications of lung resection. Predicting PAL in the early postoperative period, however, remains a challenge. In this study, we analyzed data from Thopaz^®, a digital chest drainage system, to determine the predictive factors of PAL. Between August 2019 and August 2020, we collected and analyzed data from 279 patients after lung resection, of which 57 were identified with postoperative air leaks. The incidence of PAL, which was defined as an air leak lasting for 5 postoperative days, was 12.3% (n=7). PAL occurred at a significantly higher rate in cases where the maximum volume of air leak in the 12 h after surgery was more than 800 mL/min, and when the average volume of air leak was lower in the first 6 h post-surgery than in the subsequent 6 h. The maximum volume and air leak trends detected by Thopaz in the 12 h after surgery may be useful for predicting PAL and the necessity of additional intervention.

A 71-year-old woman with a left upper lobe tumor of the lung was referred to us for surgical treatment. Thoracoscopic left upper lobectomy of the lung was performed without any intraoperative complication. The pathological diagnosis was typical carcinoid of the lung. Anticoagulant therapy (intravenous heparin) was initiated on the fifth postoperative day because paroxysmal atrial fibrillation appeared intermittently from the operative day to the third postoperative day, and it reappeared from the fifth to the eighth postoperative day. The patient developed sudden-onset abdominal pain at 12 days after surgery. Contrast computed tomography revealed an intra-atrial thrombus adhering to the stump of the left upper pulmonary vein. Infarction of the spleen and bilateral kidneys and thromboembolism of the superior mesenteric artery were also detected. Brain MRI revealed a cerebellar infarction. Intravenous heparin therapy was continued, with the aim of prolonging the partial prothrombin time, and oral warfarin was administered to improve anti-coagulation. The patient was discharged from the hospital a month after surgery while continuing to receive oral warfarin. She has been doing well without any sign of thromboembolism since then. For those with a high risk of thromboembolism (left upper lobectomy, obesity, high age, etc. ), post-operative contrast-enhanced CT should be readily performed, along with initiating appropriate anti-coagulation therapy if indicated.

We report the case of a 72-year-old man diagnosed with hyponatremia and an anterior mediastinal tumor of 13 mm in diameter at a nearby hospital. He was referred to our hospital for evaluation of the hyponatremia and anterior mediastinal tumor. He was diagnosed with syndrome of inappropriate secretion of antidiuretic hormone and treated with water restriction and salt intake for 6 months, after which his serum electrolyte levels improved. Eight months later, the tumor had grown, and we scheduled video-assisted thoracoscopic surgery. Although right lung adhesion was widely observed and the thoracoscopic technique for visualizing the operative field was difficult, we resected the tumor with complete thoracoscopic surgery. Histological analysis revealed the tumor to be anterior mediastinal neuroblastoma. Hyponatremia improved immediately after the operation, and the patient was discharged on the 7^th postoperative day. Postoperative radiation and chemotherapy were not performed, and he was well as of 20 months after surgery, without recurrence. Neuroblastoma is extremely rare in adults, and there are no conventional postoperative treatments or guidelines. We herein report the diagnosis and treatment of this condition, as well as discuss similar cases reported in the literature.

The case was a 73-year-old man. Positron emission tomography-computed tomography revealed two nodules with abnormal accumulation of F-18 fluorodeoxyglucose in the upper lobe of the left lung. The patient was placed in the right lateral decubitus position, and under general anesthesia, thoracoscopy assisted left upper lobectomy and mediastinal and hilar lymph node dissection (ND2a-1) were performed. Both tumors were poorly differentiated adenocarcinomas (pT1c[2]N0M0 stage IA3). From the first postoperative day, he complained of difficulty in raising his left upper limb due to weakness of the left deltoid muscle, and was diagnosed with axillary nerve palsy. Quadrilateral space syndrome was suspected as the cause; thus, physical therapy was initiated. From the first postoperative month, clenching the left hand into a fist gradually became possible. Two months after the operation, he recovered to the extent that the disability did not interfere with his daily life and soon recovered his muscle strength. Five years after the operation, he was followed up as an outpatient; no recurrence or disability in the upper left limb was noted. Quadrilateral space syndrome as a complication of chest surgery is rare. However, we should accumulate cases to further understand the anatomical structure of the axillary nerve and its surroundings, and standardize the limb position without pressure or hyperextension.

[Background] Chest wall hemangiomas account for about 1% of chest wall tumors, and intramuscular hemangioma arising from intercostal muscle is extremely rare, accounting for 0.01% of all hemangiomas. [Case] In a 54-year-old woman, a 3.0-cm chest wall mass was found between the left 3rd and 4th ribs on examination by CT. PET/CT showed FDG accumulation by the mass (SUVmax: 2.3), and CT-guided needle biopsy was performed for a definitive diagnosis, revealing no malignant findings. During a 2-month follow-up, MRI showed that the mass was not growing, a malignant tumor such as desmoid tumor was suspected, and tumor resection was performed. The chest wall mass was a mural extrathoracic lesion consisting of a collection of bluish-purple multilocular nodules under thoracoscopic view. No malignant findings were found by intraoperative biopsy. However, according to previous reports of local recurrence of intercostal hemangiomas, chest wall resection including the third rib was performed. No malignant findings were found in the final pathological diagnosis, and the lesion was diagnosed as intramuscular hemangioma arising from intercostal muscle. [Conclusion] Although it is difficult to make a definitive diagnosis of intercostal hemangioma before surgery, it is important to list hemangioma as a differential diagnosis based on preoperative radiological findings and to perform complete resection of the tumor.

We report a rare case of resection of pulmonary MALT lymphoma that occurred after resection of large cell neuroendocrine cancer. The patient was a 70-year-old woman. She underwent right lower lobectomy for stage IA2 right pulmonary large cell neuroendocrine carcinoma. On the suspicion of stage IA second lung cancer because a ground-glass nodule appeared in the middle lobe of the right lung on chest CT 5 years after the operation, thoracoscopic right middle lobe resection was performed. Histopathologically, she was diagnosed with pulmonary MALT lymphoma. Now, at 8 months after the operation, there has been no recurrence and the patient is being followed up. MALT lymphoma is associated with chronic inflammation due to various factors, but there are limited reports of lung MALT lymphoma associated with lung cancer. Further case accumulation is needed to clarify the relationship between the two diseases and treatment policy.

Concomitant surgery for a mediastinal tumor and cardiac disease by median sternotomy is rare. A 72-year-old woman who complained of dyspnea on exertion was diagnosed with severe mitral valve regurgitation. Chest CT revealed an anterior mediastinal tumor with a diameter of 57 mm. Tumor invasion to the left brachiocephalic vein was suspected by enhanced chest MRI. Examination for elevation of acetylcholine receptor antibody disclosed concomitant myasthenia gravis (MGFA type IIB). After treatment for myasthenia gravis was started, concomitant surgery for thymoma and mitral valve regurgitation was performed. Firstly, an extended thymectomy by median sternotomy was performed. The left brachiocephalic vein was partially resected and sutured because of tumor invasion. The intraoperative rapid diagnosis was type B3 thymoma, and continuously, mitral valve plasty and tricuspid valve annuloplasty were performed. She was discharged on the 14th postoperative day with no complications. Pathological findings of the resected specimen revealed type B3 thymoma with multiple metastases to lymph nodes and invasion to the left brachiocephalic vein. She received no adjuvant therapy due to concerns over cardiac toxicity of anticancer drugs or pericarditis by radiation therapy. She now continues strict follow-up.

Thoracentesis and pleurodesis are selected for difficult-to-control intractable pleural effusion, but complications associated with puncture and adverse events in pleurodesis may be fatal in patients with poor PS and elderly individuals. Therefore, it is often difficult to carry out in actual clinical practice.

We herein report three 90-year-old patients with refractory pleural effusion who were successfully treated by pleuroperitoneal shunt insertion using a Denver shunt. The cause was unknown in 2 patients and malignant pleural effusion in 1. All patients underwent shunt insertion under general anesthesia. There were no complications associated with surgery, and pleural effusion symptoms were well-controlled in the outpatient clinic thereafter.

Pleuroperitoneal shunt insertion may be a very effective palliative treatment option to improve the QOL of patients with refractory pleural effusion by freeing the patient from symptoms of respiratory distress and frequent thoracentesis procedures. In addition, it will reduce the labor of caregivers, including family members. We consider that the benefits will be marked for both patients and caregivers.

Anticoagulant is used to treat pulmonary vein stump thrombus after left upper lobectomy. However, the optimal length of anticoagulant therapy remains controversial. We report a case of pulmonary vein stump thrombus that regenerated after discontinuation of anticoagulation therapy despite the fact that the thrombus had disappeared after such therapy. A 71-year-old man underwent left upper lobectomy for lung cancer. Three months after the operation, contrast-enhanced CT showed a thrombus in the left superior pulmonary vein stump, and anticoagulant therapy was administered for three months. Irrespective of the disappearance of the left superior pulmonary vein stump thrombus, it regenerated 3 months after the discontinuation of anticoagulant. The newly regenerated thrombus disappeared after readministration of the anticoagulant. There is no report on patients with a recurred pulmonary vein stump thrombus after primary anticoagulant therapy. This case alerts us to the possibility of late postoperative development of pulmonary vein thrombus after successful primary treatment.

In January 2020, a 79-year-old man underwent laparoscopic low anterior resection and covering ileostomy for rectal cancer. Seven months later, chest contrast-enhanced computed tomography (CT) showed a 30-mm nodule in segment 10 of the left lung that had not been present before the operation. Thoracoscopic wedge resection of segment 10 was performed. Histopathologically, the nodule was infiltrated with IgG4-positive plasma cells. The rate of IgG4-positive to IgG-positive cells was about 55%, and the nodule was diagnosed as showing IgG4-related pulmonary disease. However, other lesions of IgG4-related disease were not found.

A 55-year-old man had pain in his left shoulder and scapula. CT showed a tumor at the apex of the left lung, and PET-CT showed a high accumulation with SUVmax 9.74. CT-guided tumor biopsy revealed adenocarcinoma. He was diagnosed with left upper lobe lung cancer cT3N0M0 c-stage IIB. We performed a left upper lobectomy and resected the first to third ribs and dissected hilar and mediastinal and left supraclavicular lymph nodes. The size of the resected specimen was 6.0 × 5.0 × 3.6 cm. Pathological examination revealed that the center of the lesion was the parietal pleura that invaded the ribs and lungs. Tumor cells were arranged in trabecular, glandular, papillary, and microtubular growth patterns, partially with abundant stroma. Immunohistochemical staining revealed a localized malignant pleural mesothelioma of the epithelial type. Lymph node metastasis was found only in the left supraclavicular lymph node, and the diagnosis was pT4N2M0 pStage IIIB. He has been followed up for nine months since surgery without signs of recurrence.

Tuberculosis is one of the rare causes of descending necrotizing mediastinitis. We report a case of descending necrotizing mediastinitis resulting from tuberculous retropharyngeal abscess.

A 70-year-old female who was previously diagnosed with military tuberculosis with polymyositis visited our hospital. She presented with dysphagia and was diagnosed with a retropharyngeal abscess. She started taking antituberculosis medications; however, after one month, the abscess had spread to the posterior mediastinum and was diagnosed as descending necrotizing mediastinitis. We performed surgical drainage of both cervical and mediastinal abscesses. Since tuberculosis was detected in both abscesses, we made an overall diagnosis of descending necrotizing mediastinitis of tuberculosis. After surgical drainage, we performed additional drainage of the dorsal subcutaneous abscesses. The purulent fluid was regularly extracted via thoracic drainage for 53 days until the fluid became normal. She continued to take antituberculosis medications, and was discharged 1 year later.

Descending necrotizing mediastinitis of tuberculosis most likely takes a long course, which would be specific to tuberculosis.

A 47-year-old man with complaints of right back pain and dyspnea was admitted to our hospital. A blood test showed an increased inflammatory response, and chest computed tomography showed right pleural effusion and a 4.0-cm mass on the right posterior mediastinum. After the administration of antibiotics, the inflammatory response improved. Because a mediastinal tumor was suspected, surgical resection was performed. Histopathological findings revealed extralobar pulmonary sequestration (EPS) with hemorrhagic necrosis. We report a rare case of EPS which was detected by the symptom of pleuritis with an adult onset.

A 67-year-old woman with cough and fever visited a nearby clinic. Chest contrast-enhanced computed tomography (CT) revealed an aberrant artery with a diameter of 20 mm arising from the descending aorta and entering the left basal segment. She was diagnosed with anomalous systemic arterial supply to the basal segment and referred to our institution for surgical intervention. Surgery was performed through two access windows (5th and 7th intercostal spaces) and two ports (7th and 8th intercostal spaces). Suture of the aortic wall was performed under both direct and thoracoscopic views, while other intrathoracic procedures were performed only under a thoracoscopic view. The diameter of the aberrant artery was large, as can be noted on the preoperative CT, and we were concerned about an aneurysm at the site of the vascular cut end; therefore, the aberrant artery was dissected and sutured at the descending aorta wall after side-clamping at the origin of the aberrant artery. After the aberrant artery was dissected, blood flow from the pulmonary artery to left lower lobe was confirmed using the indocyanine green fluorescence method. Thus, a decrease in the blood flow to the entire left lower lobe was confirmed, and the left lower lobe was resected. Postoperative pathological examination revealed a thin tunica media and thick tunica intima of the aberrant artery. Disrupted elastic fibers and myxoid change were also observed in the tunica media. Her postoperative course was uneventful, and no abnormality was observed in the aortic wall at 19 months postoperatively. Our case suggested the possibility of tissue fragility of the vessel wall if the diameter of the aberrant artery was large. The method of treating the aberrant artery should be considered carefully for each case.

In the case of surgery for advanced thymic epithelial tumors invading the superior vena cava (SVC) or left brachiocephalic vein (LBCV), combined resection and revascularization with a vascular graft may be required. However, the graft may be obstructed due to thrombosis and anatomical factors. We report a case of resection of thymic carcinoma infiltrating SVC and LBCV, while preserving the collateral circulation via the azygos vein. An 80-year-old woman was referred to our hospital after being diagnosed with an anterior mediastinal tumor. Enhanced computed tomography (CT) showed the tumor obstructing SVC and LBCV. Although upper body swelling and facial edema were absent, three-dimensional reconstruction CT showed an expanded azygos vein and marked collateral circulation. Focusing on preservation of the collateral circulation via the azygos vein, we resected the tumor that infiltrated SVC and LBCV without vascular reconstruction. The final pathological diagnosis was thymic carcinoma. Postoperative CT showed preserved flow through the azygos vein without compression. In cases of advanced thymic tumor infiltrating SVC and LBCV with marked collateral circulation via the azygos vein, preservation of the azygos vein may be an alternative to vascular reconstruction.

We report a rare case of pleural tuberculosis after lobectomy for lung cancer. A 67-year-old man without a history of pleural tuberculosis developed lung cancer with cStage IA2 (T1bN0M0). We performed thoracoscopic right upper lobectomy with the dissection of lymph nodes. Intraoperative pleural effusion cytology confirmed malignant cells, and the pathological stage was IVA (T1bN1M1a). The patient was treated with postoperative chemotherapy (Carboplatin+Pemetrexed 6 courses). Rt. pleural effusion disappeared 4 months after the surgery, but a follow-up chest radiograph and chest computed tomography (CT), 8 months after surgery, showed rt. pleural effusion. Pleural effusion cytology did not confirm malignant findings, but a polymerase chain reaction (PCR) test of pleural effusion and pleural effusion culture for Mycobacterium tuberculosis were positive. Anti-tuberculosis drugs were administered for 6 months. He has been followed up without the relapse of pleural tuberculosis. We must include pleural tuberculosis in the differential diagnosis of pleural effusion in patients receiving surgery for lung cancer.

A 63-year-old man was admitted to our hospital for refractory empyema due to anastomotic leakage after bronchoplasty. The patient underwent distal gastrectomy for gastric ulcer and right lower sleeve lobectomy for pulmonary squamous cell carcinoma 30 and 2 years ago, respectively. The pathological stage of the patient was confirmed as stage IIB (pT2aN1M0) after the pulmonary resection, and four courses of postoperative chemotherapy with cisplatin and docetaxel were performed. Nine months after the pulmonary resection, the patient developed empyema due to bronchial anastomotic leakage. Open window thoracotomy was then performed. Although the patient's intrathoracic cavity reduced after open window thoracotomy, his dyspnea and dysphonia worsened due to exacerbation of the bronchial fistula. Therefore, the patient was referred to our hospital for thoracic stoma closure. A free left rectus abdominis musculocutaneous flap was prepared for stoma closure. A pedicle of the left inferior epigastric artery and vein was anastomosed to the right subscapular artery and vein, respectively. The free musculocutaneous flap was transposed to the thoracic cavity and the fistula was sealed with this flap. Appropriate precautions were taken to prevent occlusion of the tracheal lumen. Postoperative bronchoscopy revealed no airway obstruction due to the filling flap. Moreover, no evidence of recurrence of empyema was reported during 2 years of observational follow-up.

Intrathoracic schwannomas account for approximately 20% of mediastinal tumors; however, vagus nerve-derived schwannomas are rare. Herein, we report a vagus nerve-derived schwannoma under the aortic arch that showed marked accumulation of fluorodeoxyglucose (FDG), presented with intermittent hoarseness, and was completely resected by thoracoscopic surgery. The patient, a 78-year-old woman, presented with hoarseness and was found to have a 60-mm mediastinal tumor that was diagnosed as a schwannoma by ultrasound bronchoscopic biopsy. Considering the marked accumulation of FDG, nerve compression syndrome, and malignant potential, the tumor (including nerve sheath) was resected. The histopathological diagnosis was a benign schwannoma. The hoarseness resolved after the surgery. Vagus nerve-derived schwannomas abutting surrounding vital organs may be resectable by thoracoscopic surgery.