Background: Currently, inhaled nitric oxide (NO) therapy for lung transplantation is not covered by public health insurance in Japan. In this study, we evaluated the perioperative use and safety of inhaled NO therapy for lung transplantation.

Methods: Data regarding the duration of treatment and adverse events of inhaled NO therapy were collected for all lung transplantations performed from January 1, 2015, to December 31, 2019, at nine lung transplant facilities in Japan.

Results: During the study period, lung transplants were performed for 357 patients, among whom inhaled NO therapy was administered to 349 patients (98%). The median initial and median maximum inhaled NO doses were 10 and 20 ppm, respectively. Inhaled NO therapy was introduced during surgery and continued postoperatively in 313 patients (90%) for a median of 4 days. Significant improvements in oxygenation and decreases in pulmonary arterial pressure were observed in patients receiving inhaled NO therapy. Side effects of inhaled NO therapy, such as methemoglobinemia, were observed in 15 patients (4%), with a significant incidence in patients aged < 18 years.

Conclusions: Inhaled NO therapy was performed for almost all patients who underwent lung transplantation in Japan and showed reasonable efficacy. Therefore, public health insurance coverage for inhaled NO therapy during lung transplantation is recommended.

Background: Pulmonary embolism associated with deep vein thrombosis is widely known to cause pulmonary artery thrombosis. However, the significance of pulmonary artery stump thrombosis after pulmonary resection remains unclear because of the lack of published information. The aim of this study was to identify risk factors of pulmonary artery stump thrombosis after anatomical pulmonary resection.

Methods: We retrospectively investigated 58 patients who were examined using contrast-enhanced computed tomography after anatomical pulmonary resection between December 2019 and December 2021, and analyzed the risk factors of pulmonary artery stump thrombosis.

Results: Pulmonary artery thrombosis was observed in 10 (17%) patients, including one patient with multiple pulmonary embolisms with deep vein thrombosis and nine patients with pulmonary artery stump thrombosis. All nine patients showing pulmonary arteries with confirmed stump thrombosis had significantly longer stumps and were resected using staplers.

Conclusions: Most cases of pulmonary artery thrombosis were caused by pulmonary artery stump thrombosis after anatomical pulmonary resection. A longer stump was one of the risk factors.

The left ventricular ejection fraction (LVEF) is a common indicator of the left ventricular systolic function. We studied the perioperative outcomes of seven patients with LVEF of <40% during lung cancer surgery conducted between 2020 and 2021. There were six males and one female with a mean age of 75.7 years. One patient had mild preoperative heart failure (NYHA classification II) with a mean LVEF of 31.7% (24.6-38.4%), and there were two patients with LVEF of <30% (24.6 and 25.2%). The decrease in LVEF was caused by (some overlapping) ischemic heart disease in five patients, atrial fibrillation in four patients, dilated cardiomyopathy in two patients, ventricular tachycardia in one patient, and aortic valve stenosis in one patient. The histological classifications were adenocarcinoma in four patients and squamous cell carcinoma in three patients. The pathological stages were stage 0 in one patient, stage IA in three patients, stage IIB in one patient, stage IIIB in one patients and stage IVA in one patient. As the surgical techniques, three patients underwent pulmonary lobectomy, two patients underwent segmentectomy, and two patients underwent wedge resection. Regarding postoperative complications, one patient experienced an exacerbation of heart failure (preoperatively NYHA class I, LVEF: 24.6%), but the condition improved with noninvasive positive-pressure ventilation (NPPV) and diuretics. All patients were discharged between postoperative days 7 and 10. If heart failure symptoms can be well-controlled preoperatively, lung cancer surgery may be safely performed by careful perioperative management, including patients with decreased LVEF.

Inflammatory myofibroblastic tumor (IMT) is a rare low-grade tumor that is caused by proliferation of myofibroblasts with infiltration of inflammatory cells and is sometimes diagnosed as ALK-positive. We report two cases of IMT resected at our hospital. Case 1: A woman in her 60s. Chest CT performed as a postoperative follow-up for her right femoral liposarcoma revealed a nodule in the upper lobe of the left lung. We performed wedge resection because it was suspected of being a metastatic lung tumor. While immunohistochemical staining showed no characteristic features of IMT, histological findings of the resected specimen showed proliferation of spindle cells with inflammatory cells. We diagnosed the tumor as IMT by the morphology and excluding other diseases. Case 2: A woman in her 20s. A mass shadow had been pointed out by chest radiograph on medical examination. We performed chest CT, which showed a mass in her right middle lobe that compressed part of her pulmonary arteries and veins. We first conducted a thoracoscopic biopsy. Histological findings of the resected specimen showed the proliferation of spindle cells with lymphocyte infiltration, and immunohistochemical staining showed the tumor cells to be ALK-positive. We diagnosed the tumor as IMT by the morphology and excluding other diseases, and performed thoracotomy to facilitate right middle and lower lobectomy for radical cure.

Langerhans cell histiocytosis (LCH) is a rare neoplastic disorder that occurs because of Langerhans cell infiltration of affected organs. Although LCH can occur anywhere in the body, it frequently affects the lungs in adults. Herein, we report the case of a patient with colorectal cancer who was diagnosed with LCH during the postoperative follow-up. The patient was a man in his 60s with a history of smoking one pack of cigarettes per day for 46 years. Chest computed tomography revealed multiple nodules in the lungs during the follow-up for colorectal cancer, for which the patient was operated on five years ago. Surgical biopsy was planned for suspected lung metastases; however, the histological examination revealed nodules composed of fibrous scar tissue with infiltration of eosinophils and CD1a-positive histiocytes, confirming the diagnosis of LCH. A skin biopsy was performed after lung biopsy; the results of the biopsy confirmed infiltration of the skin lesion with Langerhans cells. The nodule sizes remained stable for two years until he stopped visiting the outpatient clinic. The radiological features of LCH vary with each stage and complicate the differential diagnosis; therefore, surgical biopsy can be effective in treatment planning.

A 38-year-old woman was referred to our hospital with a diagnosis of left pneumothorax during menstruation. Despite outpatient thoracentesis and inpatient thoracic drainage, the air leak did not improve, and surgery was performed for definitive diagnosis and pneumothorax treatment. Intraoperative findings included a single bulla-like lesion at the left S5, confirmed by preoperative imaging, from which visible leakage was confirmed, with no other abnormalities, including the diaphragm. The lesion was resected, and pathological examination revealed the presence of short spindle-shaped to round-shaped small cells in the central visceral pleural thickening area and positive findings on various immunostains (CD10, ER, PgR), leading to the diagnosis of left catamenial pneumothorax. Pathologically diagnosed left catamenial pneumothorax is rare, and this time we confirmed the leakage from the left side single visceral pleural lesion during surgery, and pathologically proved and treated it.

Neuroendocrine carcinoma of the thymus is classified as a subtype of thymic carcinoma and accounts for only 2 to 4% of all anterior mediastinal neoplasms. Large cell neuroendocrine carcinoma (LCNEC) is a poorly differentiated neuroendocrine carcinoma and is associated with a poorer prognosis than other types of thymic tumors. We herein describe a resected case of thymic LCNEC. A 72-year-old man was referred to our hospital because of a mediastinal tumor that had been found during a medical checkup. Chest computed tomography showed an anterior mediastinal tumor with a diameter of 46 mm, which was heterogeneously enhanced with contrast medium and suspected of infiltrating adjacent tissue. Positron emission tomography-CT showed high FDG accumulation in the tumor. We diagnosed the tumor as a stage-III thymic tumor according to Masaoka's classification and performed total thymectomy via a median sternotomy. The final pathological diagnosis was LCNEC of the thymus in Masaoka's stage-II. The patient received adjuvant chemotherapy with cisplatin and etoposide, and has been observed without any sign of recurrence for 18 months.

A 72-year-old man underwent right upper lobectomy and right S9+10 segmentectomy for synchronous multiple primary lung cancer in 2012. As a result of repeated intrathoracic infections due to chronic pulmonary fistula, he developed empyema and open-window thoracostomy was performed in 2019. It closed within 4 months after surgery; however, bloody sputum appeared in 2021, and he was diagnosed with empyema with fistula, and open-window thoracostomy was performed again. Chest pain appeared after the secondary open-window thoracostomy, and chest CT showed an increasing low-density area in the right thoracic cavity. Multiple biopsies were performed from the empyema cavity via the thoracic window, and angiosarcoma was diagnosed by the third biopsy. Chronic empyema-associated angiosarcoma is known to be difficult to diagnose; however, if a mass appears in the thoracic cavity after treatment for chronic empyema, it is important to suspect a malignant tumor and repeatedly examine it.

We herein report a case of inflammatory myofibroblastic tumor (IMT) of the lung which caused hemothorax and hemoptysis metachronously. A 26-year-old man who had a past history of right hemothorax 2 years ago was referred to our hospital because of repeated hemoptysis. Contrast-enhanced chest computed tomography revealed a poorly-demarcated nodule in the right middle lobe with pulmonary hemorrhage. Based on the clinical course and radiological findings, we considered that the nodule caused hemothorax and hemoptysis metachronously. We therefore performed right middle lobectomy. The final pathological diagnosis of the resected specimen was IMT. He has been relapse-free for 39 months since the lung resection.

An 81-year-old male with a history of chronic atrial fibrillation, idiopathic interstitial pneumonia, and chronic obstructive pulmonary disease was treated with prednisolone and apixaban. Chest computed tomography (CT) revealed a 1.7-cm nodule in the left lower lobe. CT-guided needle biopsy (CTNB) with an 18-gauge biopsy needle was performed more than 24 h after discontinuing apixaban. We inserted a small-bore chest tube (12 Fr), because of pneumothorax. Consequently, the patient developed shock three hours after CTNB. Chest CT revealed a massive left-sided hemothorax. We performed video-assisted thoracic surgery and removed approximately 600 mL of blood. Blood oozing from the visceral pleura and underlying pulmonary parenchyma was detected at the left lower lobe, possibly at the biopsy needle insertion site, and was coagulated with electrocautery. He was discharged 9 days after the thoracic surgery. CTNB-induced hemothorax, which is often attributed to intercoastal or internal mammary arteries or veins, can be induced from visceral pleura and underlying pulmonary parenchyma, as in this case, but this is a rare and fatal complication.

Lung basaloid squamous cell carcinoma (BSC) was recognized as a subtype of squamous cell lung cancer in the eighth Edition of the General Rules for the Clinical and Pathological Classification of Lung Cancer of the Japan Lung Cancer Society. BSC is relatively rare and has many unclear points. We encountered three patients with BSC who were diagnosed by surgery. The first was a 66-year-old man. Chest computed tomography (CT) showed a tumor in the left S9 segment. He was diagnosed with limited disease small cell lung cancer by transbronchial biopsy. Left lower lobectomy was performed and a diagnosis of BSC made by histological examination of the operative specimen. Although relapse occurred 6 months after surgery, he is responding to chemotherapy. The second case was a 72-year-old man whose chest CT showed a nodule in the left S3 segment. He was diagnosed with non-small cell lung cancer by transbronchial biopsy. Left upper lobectomy was performed and a diagnosis of BSC was made by histological examination of the operative specimen. He remains alive without recurrence. The third case was a 69-year-old man with a history of interstitial pneumonia. Chest CT showed a nodule in the left S6 segment. He was diagnosed with squamous cell lung cancer by CT-guided lung biopsy. Left S6 segmentectomy was performed and a diagnosis of BSC was made by histological examination of the operative specimen. He died 6 months after surgery from an acute exacerbation of interstitial pneumonia.

A 58-year-old man diagnosed with stage IA2 pulmonary squamous cell carcinoma underwent left upper lobectomy. Although he favorably recovered, he had symptoms of right heart failure after 41 postoperative days and was emergently hospitalized due to cardiac tamponade on postoperative day 48. We administered pericardial drainage and obtained 1400 mL of bloody effusion, and removed the drain tube in three days because pericardial hemorrhage rapidly stopped. After ruling out a complication of cardiovascular disease, analysis of the intraoperative video revealed that the pericardial hemorrhage was caused by involvement of pericardial reflection by an auto stapler cutting the pulmonary vein. Cardiac tamponade after pulmonary lobectomy is an extremely rare complication and there is no report of pericardial hemorrhage from the stump of the pulmonary vein over one month after surgery. Herein, we report cardiac tamponade after lobectomy, a life-threatening complication, which emerged even though an intrapericardial procedure was not performed.

We report the case of a woman in her 50s, who presented with an abnormal shadow on a chest radiograph. Computed tomography revealed a left pleural cavity tumor (15 cm in maximum diameter), which showed a mixture of cystic and solid components. We performed a thoracotomy for complete en bloc tumor removal, together with a thymectomy. A postoperative histopathological examination confirmed the diagnosis of a type B3 thymoma, Masaoka stage I. At the time of writing this report, no tumor recurrence had been observed over a postoperative period of 24 months. This study describes a rare case of the successful surgical resection of a giant thymoma.

A 41-year-old man was referred to our department because MRI revealed a nodule with low T1 and high T2 signal intensities in the left fourth rib. CT showed internal hypo-absorption and bone destruction, and PET-CT showed hyperaccumulation in the same area. Therefore, we suspected a primary malignant tumor of the left 4th rib, and performed rib resection and chest wall reconstruction for diagnosis and treatment. The pathological diagnosis was Langerhans cell histiocytosis. Langerhans cell histiocytosis primarily occurring in the rib is rare, and there are only a few reports of such surgical cases in Japan. These lesions require careful follow-up since there have been reports of their recurrence.

An 82-year-old man underwent radical total prostatectomy for prostate cancer (pT3aN0M0, Gleason score 3+4) at the age of 75. The preoperative serum PSA level was high at 6.71 ng/mL, but the postoperative level was maintained below 0.1 ng/mL. However, at four years and eight months postoperatively, his PSA rose to 0.27 ng/mL, so he was diagnosed with PSA recurrence. At five years and nine months postoperatively, simple chest computed tomography (CT) revealed a 10-mm nodule in the right lower lobe. At seven years and two months postoperatively, the nodular shadow had increased to 14 mm, which was considered an indication for surgery. The first suspicion was lung metastasis of prostate cancer, but considering the possibility of primary lung cancer, a thoracoscopic right lower lobectomy and lymph node dissection (ND2a-1) were performed. Histopathology showed adenocarcinoma morphology, and immunohistochemical staining was positive for PSA, leading to the diagnosis of lung metastasis from prostate cancer.

Although solitary lung metastasis from prostate cancer is rare, monitoring the serum PSA level is useful for its detection, and it is important to suspect lung metastasis on observing lung nodules that appear after radical total prostatectomy, with a PSA of 0.2 ng/mL or higher as PSA recurrence.

A 75-year-old man visited his family doctor in 20XX-7 owing to an abnormal shadow on a chest radiograph revealed in a health check-up. Chest computed tomography (CT) showed a positive extrapleural sign for a 2.0-cm-diameter nodule in the left thoracic cavity. The nodule grew to a diameter of 2.9 cm in 20XX. Fluorodeoxyglucose positron emission tomography-CT showed weak accumulation. Thoracoscopic surgery was performed. The pedunculated tumor attached to the visceral pleura of the left lower lobe was removed by wedge resection. Histologically, the tumor had both a low-grade area and a high-grade sarcomatous area with high mitotic counts. From the above histological features, the tumor was diagnosed as a dedifferentiated SFT that originated from the visceral pleura. Timely follow-ups are mandatory as dedifferentiated SFT has a higher rate of recurrence or metastasis than conventional SFT.

A solitary fibrous tumor (SFT) rarely causes hypoglycemia. We report a patient with gastric cancer and an SFT, in whom marked hypoglycemia developed during the perioperative period. Chest radiograph findings showed an abnormal shadow in the left lower lung field of an 80-year-old man, which was diagnosed as an SFT based on bronchoscopy biopsy results. Additionally, gastric cancer was detected during that time; thus, a total gastrectomy was performed before treatment for the tumor. Mild fasting hypoglycemia was observed prior to the gastrectomy and it remained postoperatively, although it was asymptomatic and could be controlled with diet therapy. After discharge, the patient was brought back to the hospital due to unconsciousness and his fasting blood glucose level was extremely low. This was considered to be a symptom associated with the SFT, and resection of the tumor was performed. Following surgery, hypoglycemia was found to have resolved. High-molecular-weight insulin-like growth factor II (IGF-II) was detected in preoperative serum, and hypoglycemia as a tumor-associated symptom was diagnosed. It should be noted that hypoglycemia due to an SFT can be exacerbated during the course of the disease.

We report a patient with pre-existing interstitial pneumonia, who underwent right lower lobectomy for lung cancer, after successful recovery from COVID-19. A 75-year-old man tested positive for COVID-19, but was asymptomatic. However, his respiratory status worsened a week later, with chest CT depicting ground-glass opacities in all lung lobes, and reticular opacities, predominantly in the bilateral lung bases. A pure solid tumor, measuring 4.1 cm, was incidentally identified in the right lower lobe. After 17 days of hospitalization, he was discharged home in a satisfactory condition. Preoperative CT indicated improvement of lung opacities, and gadolinium-enhanced brain magnetic resonance imaging (MRI) and whole-body MRI revealed no metastases. Right lower lobectomy was performed 13 weeks after the initial diagnosis of COVID-19. Postoperatively, dyspnea on exertion persisted. Oxygen therapy, prescribed at hospital discharge, was administered postoperatively for 4 months, after which, it was deemed no longer necessary. At the one-year follow-up, no recurrence or metastasis was detected on examination, and the forced expiratory volume in 1 second was approximately consistent with the preoperative value.