In general, primary spontaneous pneumothorax (PSP) rarely shows a serious clinical course in young patients. Therefore, conservative therapy is normally selected to treat a first episode of pneumothorax. The recurrence rate in several publications has been reported to range from 32.1-55.6%. We often perform surgical treatment for recurrent pneumothorax. In the present study, we discuss the surgical indication for the first episode of pneumothorax with severe collapse. The recurrence rate and collapsed volume in the second episode of PSP were compared between cases with non-severe collapse and those with severe collapse. The recurrence rate in the non-severe and severe groups was 45.3 and 51.5%, respectively, while the rate of severe collapse for the second episode of PSP in the non-severe and severe groups was 9.8 and 40.0%, respectively. As a result, when managing the first episode of pneumothorax with severe collapse, surgical treatment should be selected instead of conservative therapy.

A 74-year-old woman underwent surgery for a parotid tumor 7 years earlier and was histologically diagnosed with pleomorphic adenoma. She had a medical history of Sjögren's syndrome and scleroderma and was under observation for enlargement of multiple lung nodules. CT revealed pulmonary nodules measuring 1.0 cm in the S1+2 left upper lobe, 1.4 cm in the S8 left lower lobe, and 0.6 cm in the S2 right upper lobe. All of these showed high FDG accumulation on PET-CT. First, wedge resection of the S8 and S1+2 left lung was performed, and after 3 months, wedge resection of the S2 right lung was performed. Pathological re-evaluation revealed parotid tumors that appeared 7 years before and metastases were diagnosed as myoepithelial carcinoma ex pleomorphic adenoma, and immunostaining for Ki-67 was critical in the diagnosis. We report a case of myoepithelial carcinoma ex pleomorphic adenoma with a review of the literature.

Emphysema usually progresses with prolonged exposure to tobacco smoke, which is rare in young patients. Lung cancer often occurs in patients with emphysema, which also rarely occurs in young patients. We report a case of lung cancer discovered in a pneumothorax bullectomy specimen from a young patient with severe emphysema. The patient was a 34-year-old man who had smoked 20 cigarettes/day for 4 years from the age of 14 to 17 and for 15 years from the age of 20 to 34. He had worked as a shipbuilding painter, and his older brother had a history of pneumothorax. He developed a pneumothorax (secondary to severe emphysema) for which a bullectomy was performed. Two nodules were detected in the widely resected bullae, one of which was diagnosed as poorly differentiated squamous cell carcinoma. Lung cancer may occasionally be seen in patients with pneumothorax, but most cases have been reported in elderly patients (and rarely in young patients). However, severe emphysema is common in people with a history of marked exposure to tobacco smoke, which is also known to increase the risk of lung cancer. Therefore, caution should be taken to rule out lung cancer when managing pneumothorax in young patients with severe emphysema, as seen in this case.

We report two surgical cases of pneumothorax caused by COVID-19 pneumonia due to new occurrence of bullae or blebs. Case 1: The patient was a man in his late 50s with no history of smoking. He had recovered from severe COVID-19 with the administration of oxygen, remdesivir, and dexamethasone; however, he developed right pneumothorax on the 21st day after onset and required emergency hospitalization. Computed tomography (CT) showed a lung cyst that was not found during the treatment for pneumonia. The patient's condition did not improve with drainage treatment, and he underwent thoracoscopic pulmonary cystectomy on the 10th day of admission. The pathological diagnosis was a bleb with active inflammatory changes. Case 2: The patient was a man in his early 60s with no history of smoking. Severe illness due to COVID-19 was treated, and the patient recovered as in case 1; however, on the 36th day after onset, he developed left pneumothorax and was urgently hospitalized. CT showed a lung cyst that was not found during the treatment for pneumonia. The patient's condition did not improve with drainage treatment, and he underwent thoracoscopic pulmonary cystectomy on the 20th day of admission. The pathological diagnosis was fibroelastosis, a bulla, and the healing process of bleeding and hematoma.

The main symptoms of posterior reversible encephalopathy syndrome (PRES) are caused by brain edema triggered by the breakdown of the blood-brain barrier, which includes impaired consciousness, seizures, headache, and visual impairment. This is a case of PRES, which developed postoperatively. A 62-year-old woman underwent lung resection due to a metastatic pulmonary tumor. Moreover, there was no apparent abnormality except for pain-induced hypertension (184/114 mmHg) on the second postoperative day. Head MRI was performed on the same day due to sudden generalized convulsions and visual disturbance. A hypertension-induced PRES diagnosis was made because of predominant subcortical white matter high-signal areas in the bilateral frontal, parietal, and occipital lobes. She was then treated with an antihypertensive drug and anticonvulsant. She was discharged without sequelae. In this paper, we report on PRES and its differentiation from cerebral infarction, a complication after thoracic surgery, along with a review of the literature.

The patient was a 77-year-old male who had attended our hospital for combined pulmonary fibrosis and emphysema. He was diagnosed with left pneumothorax by chest radiograph with a chief complaint of exertional dyspnea after cough. Thoracic drainage was initiated, and slight air leakage was identified only on exertion. On the seventh day, a chest radiograph revealed an infiltrative shadow in the right upper lung field, and chest computed tomography revealed consolidation in the right upper lobe of the lung and a thoracic drain in the left upper lobe of the lung. However, the patient showed respiratory failure due to concurrent pneumonia; hence, we decided to improve his respiratory condition while the drain was in place. The thoracic drain was removed under general anesthesia on the 28th day. Intraoperative findings revealed a fistula at the lung puncture site due to the thoracic drain; however, there was no evidence of air leakage or bleeding from the site. The patient was discharged on postoperative day 43.

Lung injury caused by the placement of a thoracic drain is often treated with emergency surgery, but elective surgery, as in this case, is rare. It is thus suggested that elective thoracic drain removal should be a treatment option if the patient's respiratory condition is unstable but the pneumothorax is under control.

A 25-year-old female was referred to our hospital with an abnormal shadow on a chest radiograph during a medical check-up. She had no past medical history. Chest computed tomography revealed a posterior mediastinal tumor. Contrast-enhanced chest magnetic resonance imaging showed strong staining of the tumor. Iodine-123 metaiodobenzylguanidine scintigraphy (¹²³I-MIBG) showed no abnormal accumulation of ¹²³I-MIBG in the tumor. She underwent thoracoscopic mediastinal tumor resection. During the resection, her systolic blood pressure increased to over 200 mmHg, but it quickly returned to the normal range after the resection. The postoperative course was good; the chest tube was removed on the first postoperative day, and she was discharged on the third postoperative day. She is currently under follow-up without treatment, and no recurrence has been observed. We encountered a case of posterior mediastinal paraganglioma in a young woman who had a negative preoperative ¹²³I-MIBG scintigram. Although paragangliomas in the posterior mediastinum are rare, the possibility of false-negative ¹²³I-MIBG scintigraphy should be kept in mind during surgery.

Herein, we report a case where negative pressure wound therapy (NPWT) was used for recurrent chronic expanding hematoma. An 83-year-old man underwent a right lower lobectomy for primary lung cancer. Postoperative computed tomography (CT) revealed encapsulated pleural effusion in the right thoracic cavity that slowly increased over 3 years. Cytological examination of the pleural fluid revealed no malignancy, and a diagnosis of chronic expanding hematoma (CEH) was made. Thoracoplasty (resection of the 5th to 10th ribs) was performed. Five months after the thoracoplasty, contrast-enhanced CT showed a 14 × 10 cm area of fluid accumulation in the right subcutaneous region of the chest, which was diagnosed as recurrence of CEH. There was no improvement, despite pleurodesis with OK-432. Thus, the patient underwent open-window thoracostomy, followed by NPWT for 9 weeks. The wound had almost completely healed, and the patient was free of CEH recurrence for 1 year and 1 month after the third surgery. To the best of our knowledge, there have been no reports of patients undergoing NPWT for recurrent CEH. In conclusion, NPWT is useful for treating CEH.

Lung transplantation is used for end-stage respiratory failure, often resulting in improvement in the quality of life (QOL) as well as prognosis. On the other hand, when physical symptoms continue or a life-threatening condition is presented, such as a malignant tumor associated with immunosuppression, lung transplant recipients with a serious illness may benefit from palliative care, although they rarely receive it. Here, we report a patient who was able to continue employment because of collaboration between a university hospital and a palliative home care provider. A 60s female with lymphangioleiomyomatosis underwent left lung transplantation, after which a polymorphic post-transplant lymphoproliferative disorder developed in the ascending colon eight years later. Although tumor regression did not occur with immunosuppressant adjustment and rituximab treatment, the patient requested not to receive any further chemotherapy. While continuing immunosuppressive therapy at the outpatient department of a university hospital, a home doctor began palliative care, although PTLD-induced perforated peritonitis developed one year six months later. Conservative treatment was continued and immunosuppressant therapy was adjusted, resulting in improvement in the peritonitis. Palliative care at home enabled the patient to continue working. Complementary intervention with the combination of therapeutic treatment and palliative care made it possible for the patient to live at home, resulting in a good QOL along with ensured safety, even under these conditions. Palliative care may maximize the benefits of lung transplantation.

<Case>

A 69-year-old man with left chest pain consulted a previous hospital. Chest computed tomography (CT) revealed a 9-cm tumor in the lower lobe of the left lung. The serum level of IL-2R -a tumor marker- was high (1310 U/mL). Transbronchial biopsy was performed, but it did not lead to any definitive diagnosis. A blood test showed an inflammatory response. Suspecting a pulmonary abscess, antibiotic therapy was initiated. CT performed a month later revealed a larger tumor and complete atelectasis of the left upper lobe. The patient was admitted to our hospital. We planned an operation for diagnosis and treatment. We eventually performed biopsies due to adhesion around the hilus of the lung. The histological diagnosis was EBV-positive pulmonary LYG. The patient received chemotherapy corresponding to that administered for diffuse large B-cell lymphoma and achieved a partial response and re-expansion of the left upper lobe. The IL-2 level has been normal since (421 U/mL).

<Conclusion>

Clinicians should be aware of LYG when suspected cases of lung abscess show no improvement despite antibiotic administration.

A 79-year-old man with lung cancer underwent robot-assisted right upper lobectomy. An endoscopic stapler divided the interlobar fissure between the upper and middle lobes. On postoperative day 3, a chest radiograph showed middle-lobe atelectasis. Contrast-enhanced computed tomography showed the absence of blood flow in the pulmonary vein and obstruction of the middle-lobe bronchus. The staple line on the middle lobe was observed on the interlobar plane in the lower lobe, which led to the diagnosis of middle lobar torsion. Emergency video-assisted thoracoscopic surgery was performed. A 90-degree counterclockwise rotation of the middle lobe was noted with a dark violet surface, suggestive of congestion. The middle lobe was repositioned uneventfully. After reviewing the video of the first surgery, the staple line on the middle lobe had already been found on the interlobar plane of the lower lobe at the end of surgery. Middle lobar torsion after right upper lobectomy may be prevented and diagnosed by paying attention to the staple line on the middle lobe.