The effect of polyglycolic acid sheet in preventing postoperative recurrent pneumothorax: a prospective cohort study.

BACKGROUND: Primary spontaneous pneumothorax occasionally relapses, even after bullectomy; therefore, coverage of the bullectomy staple line for pleural reinforcement is common in Japan. However, the appropriate covering materials have not yet been determined. METHODS: This was a longitudinal prospective cohort study. Data were available for patients aged < 40 years with primary spontaneous pneumothorax who underwent their first thoracoscopic bullectomy between July 2015 and June 2021. We used oxidized regenerated cellulose (ORC) sheets from July 2015 to June 2018, and polyglycolic acid (PGA) sheets from July 2018 to June 2021. The postoperative recurrence-free survival rate was evaluated. The characteristics of the recurrent cases (radiographic, intraoperative, and pathological findings) were also evaluated. The extent of pleural adhesions was classified into the following three groups: none, medium, or extensive. RESULTS: A total of 187 patients were included in the study. There were 92 and 95 participants in the ORC and PGA sheet groups, respectively. The postoperative recurrence-free survival rates were significantly higher in the PGA sheet group than in the ORC sheet group (ORC group vs. PGA group, 82.9% vs. 95.4%, p = 0.031). In recurrent cases, there was a significant difference in terms of pleural adhesion (0.0% [12 of 12, none] vs. 100.0% [four of four, extensive], p < 0.001). CONCLUSIONS: Compared with ORC sheets, PGA sheets are an effective material for preventing early recurrence of primary spontaneous pneumothorax. Strong local pleural adhesions potentially contribute to decreasing recurrence.

Lymph node dissection in thymic carcinomas and neuroendocrine carcinomas.

OBJECTIVES: Although lymph node (LN) metastases are not uncommon in thymic carcinomas, preoperative LN evaluation, intraoperative lymph node dissection (LND) and postoperative outcomes remain unknown. The aim of this study was to elucidate the characteristics of and outcomes in patients with thymic carcinomas and thymic neuroendocrine carcinomas undergoing LND. METHODS: A retrospective chart review was performed using our multi-institutional database to identify patients who underwent resection and LND for thymic carcinoma or thymic neuroendocrine carcinoma between 1991 and 2018. An enlarged mediastinal LN was defined as having a short-axis diameter >1 cm. We assessed survival outcomes using the Kaplan-Meier analysis. RESULTS: N1-level LND was performed in 41 patients (54.6%), N2-level LND in 14 patients (18.7%) and both-level LND in 16 patients (21.3%). Pathological LN metastasis was detected in 20 patients (26.7%) among the 75 patients undergoing LND. There was a significant difference in the number of LN stations (P = 0.015) and metastasis factor (P = 0.0042) between pathologically LN-positive and pathologically LN-negative patients. The sensitivity of enlarged LNs on preoperative computed tomography was 18.2%. There was a tendency towards worse overall survival of pathologically N2-positive patients, although the difference was not statistically significant (P = 0.15). CONCLUSIONS: Preoperative CT appears to play a limited role in detecting pathological LN metastases. Our findings suggest that the significance of N1- and N2-level LND should be evaluated in prospective studies to optimize the postoperative management of patients with thymic carcinomas and neuroendocrine carcinomas.

Are volume-dependent parameters in positron emission tomography predictive of postoperative recurrence after resection in patients with thymic carcinoma?

This study aimed to investigate the association between the volume-dependent parameters in 18F-fluorodeoxyglucose-positron emission tomography (18F-FDG PET/CT) and a recurrence of thymic carcinoma. A retrospective chart review was performed based on our multi-institutional database to identify patients undergoing PET prior to resection of thymic carcinoma or neuroendocrine carcinoma between 1991 and 2018. The PET parameters (metabolic tumor volume and total lesion glycolysis) were evaluated retrospectively. The relevant factors were extracted and a survival analysis was performed using the Kaplan-Meier method. Sixteen patients were thus deemed to be eligible for analysis. The median follow-up period following resection was 2.65 years (range: 0.96-0.68 years). The recurrence-free survival was significantly longer in patients with a metabolic tumor volume < = 22.755 cm3 and with total lesion glycolysis < = 105.4006 g/mL (p = 0.001 and 0.001, respectively, by a log-rank test). The metabolic tumor volume and total lesion glycolysis may, therefore, be predictive of the postoperative recurrence of thymic carcinoma.

The treatment and survival of patients with postoperative recurrent thymic carcinoma and neuroendocrine carcinoma: a multicenter retrospective study.

PURPOSE: There are few data available on the outcomes of postoperative recurrent thymic carcinoma (TC) and thymic neuroendocrine carcinoma (TNEC). The aim of this study is to evaluate the treatment and survival in patients with recurrent TC and TNEC after undergoing surgical resection. METHODS: A retrospective chart review was performed using our multicenter database to identify patients with a postoperative recurrence of TC and TNEC from 1995 to 2018. The clinicopathological factors were reviewed and the survival outcomes were analyzed. RESULTS: Sixty patients were identified among 152 patients who underwent resection of TC and TNEC. The median follow-up period from the first recurrence was 14.8 months (range 0-144). The 5-year post-recurrence survival was 23% for the whole cohort. According to a univariable analysis, advanced stage [hazard ratio (HR) 2.81, 95% confidence interval (CI) 1.09-9.54], interval between primary surgery and recurrence (HR 0.97, 95% CI 0.95-0.99), any treatment for recurrence (HR: 0.27, 95% CI 0.13-0.58) and chemotherapy for recurrence (HR: 0.46, 95% CI 0.22-0.95) were significant factors related to post-recurrence survival. CONCLUSIONS: Chemotherapy rather than surgery appears to be the mainstay treatment for managing patients with postoperative recurrent TC and TNEC and it may also be considered in multidisciplinary management. Further studies with a larger sample size are required to confirm our findings.

Clinicopathological significance of staple line coverage with an oxidized regenerated cellulose sheet after bullectomy for primary spontaneous pneumothorax.

BACKGROUND: Oxidized regenerated cellulose (ORC) sheet, in surgery of primary spontaneous pneumothorax, is used to reinforce the visceral pleura around the staple line coverage aiming to prevent a postoperative recurrence. We evaluated the effect of ORC on recurrence within 2 years after surgery. METHODS: A total of 201 patients aged < 40 years who underwent bullectomy for primary spontaneous pneumothorax at our institution were retrospectively reviewed. They were classified into an ORC sheet coverage group (ORC group, n = 100) and a non-coverage group (n-ORC group, n = 101). Two-year recurrence-free survival rates are assessed between the two groups with associated analysis of radiographical and operative findings. RESULTS: ORC had no effect on the recurrence rate. CT images and re-operative findings showed regenerated bullae in 19 and 14 patients, close to staple lines in 14 and 11 patients, respectively. White pleural thickening within the covered area was observed in all patients of the ORC group. Pathological findings also showed pleural thickening in eight patients and bulla regeneration under pleural thickening in six patients. CONCLUSIONS: Coverage with an ORC sheet after bullectomy did not prevent the regeneration of bullae and postoperative recurrence, regardless of exerting a reinforcement effect on the visceral pleura histologically.

Survival outcomes of resection for pulmonary malignancies including non-small cell lung cancer and pulmonary metastasis after esophagectomy for esophageal carcinoma.

OBJECTIVES: This study investigated survival outcomes of resection for pulmonary malignancies after esophagectomy for esophageal carcinoma, comparing non-small cell lung cancer and pulmonary metastases. METHODS: We retrospectively reviewed consecutive patients who underwent resection for pulmonary malignancies after esophagectomy for esophageal carcinoma between 2009 and 2018. The overall survival and relapse-free survival rate were assessed using Kaplan-Meier analysis. RESULTS: Eleven patients had non-small cell lung cancer and eight patients had pulmonary metastases from esophageal carcinoma. The 5-year overall survival rate was 92.9% in all patients with a median follow-up period of 50.4 (range: 9.1-130.2) months. While the 5-year overall survival rate was 100.0% in patients with non-small cell lung cancer, it was 85.7% in patients with pulmonary metastases from esophageal carcinoma. The 5-year relapse-free survival rate was 85.7% in patients with non-small cell lung cancer. CONCLUSIONS: Our data suggest that resection for pulmonary malignancies after esophagectomy for esophageal carcinoma is associated with favorable survival outcomes and should be considered in selected patients.

Survival outcomes of patients with high-grade and poorly differentiated thymic neuroendocrine carcinoma.

High-grade and poorly differentiated thymic neuroendocrine carcinoma is the rarest entity in thymic epithelial tumours. The aim of this study is to report survival data in a multi-institutional database in comparison to data in the literature. Retrospective chart review was performed on the basis of our multi-institutional database to identify patients undergoing the resection of poorly differentiated thymic neuroendocrine carcinoma between 1991 and 2018. Relevant factors were extracted, and survival analysis was performed using the Kaplan-Meier method. Twenty-one patients were identified. Five-year overall survival and recurrence-free survival were 64.6% and 51.8%, respectively. Twelve (57.1%) patients had recurrences. Due to the scarcity of data reported in the literature, our data may be used as a standard in high-grade and poorly differentiated thymic neuroendocrine carcinoma.

Efficacy and safety of surgery for spontaneous pneumothorax in elderly patients.

OBJECTIVES: There is no clear consensus on the surgical indications for spontaneous pneumothorax in elderly patients. In this study, we aimed to assess the efficacy and safety of surgical treatment of spontaneous pneumothorax in patients aged ≥70 years. We also sought to identify the risk factors for postoperative prolonged air leaks and complications in such patients. METHODS: Data pertaining to 104 elderly patients who underwent surgery out of 206 patients (aged ≥70 years) who were diagnosed with spontaneous pneumothorax at our institution between 1994 and 2018 were retrospectively reviewed. The incidences of postoperative persistent air leaks (≥2 days) and postoperative complications (≥grade 3; Clavien-Dindo classification) were analysed for efficacy and safety assessment, respectively. RESULTS: Median postoperative air leaks continued for 0 days (range 0-25); 14.4% patients developed ≥grade 3 postoperative complications. On the basis of results of multivariable analysis, it was observed that a higher PaCO2 level was significantly associated with prolonged postoperative air leaks [odds ratio (OR) 1.08, 95% confidence interval (CI) 1.00-1.17; P = 0.047]. Poorer performance status was associated with a significantly increased risk of postoperative complications, as assessed by multivariable analysis (OR 6.13, 95% CI 1.38-27.3; P = 0.017). The recurrence rate was 4.8%; mortality rate of patients was 2.9%. Three-year survival rate after surgery was 73.8%. CONCLUSIONS: Surgical treatment of spontaneous pneumothorax may be effective and safe in selected elderly patients. Moreover, higher PaCO2 and poorer performance status were independent risk factors for postoperative persistent air leaks and complications, respectively.

Low incidence of and mortality from a second malignancy after resection of thymic carcinoma†.

OBJECTIVES: Previous studies have suggested that a second malignancy often develops after resection of thymoma; however, it remains unknown whether this is applicable to thymic carcinoma. METHODS: A retrospective chart review was performed based on our multi-institutional database of resected thymic epithelial tumours between 1991 and 2016. A second malignancy was defined as newly diagnosed after thymic tumour resection. The cumulative incidence of and related death from a second malignancy after thymic and neuroendocrine carcinoma resections were estimated using a competing risk model and were compared to those of patients undergoing a thymoma resection. RESULTS: Two hundred and thirty-eight patients were identified (thymic carcinoma 59; thymoma 179). A second malignancy developed in 1 patient (1.7%) with thymic carcinoma and in 17 patients (9.5%) with thymoma. Deaths from second malignancies were noted in 7 patients with thymoma. There was a tendency towards a lower cumulative incidence of and a lower cumulative death from a second malignancy after thymic carcinoma resection (P = 0.139 and P = 0.20, respectively) than after thymoma resection. The cumulative incidence of a second malignancy in patients with thymic carcinoma was 2.8% at 5 years and at 10 years (8.0% at 5 years and 11.8% at 10 years in patients with thymoma). CONCLUSIONS: After resection of thymic and thymic neuroendocrine carcinoma, the probability of developing a second malignancy, as well as mortality from a second malignancy, is very low. A prospective study with a larger sample size is required to validate our results.

Survival outcomes after minimally invasive thymectomy for early-stage thymic carcinoma.

Minimally invasive surgery (MIS) has occasionally been used for selected patients with thymoma, but there is little information on the MIS approach for thymic carcinoma. The aim of this study was to evaluate survival outcomes after MIS for early-stage (Masaoka stage I-II) thymic carcinoma and thymic neuroendocrine carcinoma. A retrospective chart review of the cases recorded in our multi-institutional database was performed to identify patients who underwent resection for thymic carcinoma between 1995 and 2017. MIS thymectomy was performed in 17 cases (VATS, n = 14; RATS, n = 3. male, 41%; median age, 72 years). The median follow-up period was 32.7 (range 7.4-106) months. The five-year overall survival and relapse-free survival rates were 84.4% and 77.8%, respectively. The present study demonstrated encouraging preliminary results regarding MIS for the treatment of early-stage thymic carcinoma and thymic neuroendocrine carcinoma. Further studies with a larger sample size are required to evaluate the indications for this surgery.

Multifocal thymic cysts with cholesterol granuloma.

A 56-year-old female presented to our department with chest discomfort. Contrast-enhanced computed tomography (CT) revealed a cyst and nodule in the anterior mediastinum; positron emission tomography-CT showed an increased uptake in the nodule. Total thymectomy was performed to obtain a definitive diagnosis and treatment. A pathological diagnosis of multifocal thymic cysts with cholesterol granuloma was made. Microscopic examination revealed different-sized cysts scattered in the thymus. These cysts were filled with cholesterol clefts and manifested three different phase characters. The nodule comprised granuloma-containing cholesterol clefts. We report a rare case of a patient whose histopathology presented a series of cholesterol granuloma formations.

Second malignancy versus recurrence after complete resection of thymoma.

Background Patients undergoing complete resection of thymoma occasionally develop a recurrence of thymoma; they are also at risk of developing a second malignancy. The objective of our study was to compare the incidence and mortality of a second malignancy versus a recurrence of thymoma during the postoperative follow-up period after complete resection of thymoma. Methods A retrospective chart review was performed on our prospectively maintained database to identify patients undergoing complete resection of thymoma at our institution between 1991 and 2016. The incidence and related mortality of a second malignancy or recurrence of thymoma were recorded. Results One hundred and sixty-four patients were identified. Follow-up ranged from 1 to 239 months (median 54 months). During follow-up, 12 patients had a recurrence of thymoma and 14 developed a second malignancy. The mean risk ratio of recurrence to second malignancy was 0.58 (95% confidence interval: 0.48-0.69) at 5 years, 0.58 (95% confidence interval: 0.49-0.68) at 10 years, and 0.51 (95% confidence interval: 0.43-0.60) at 15 years. The mean risk ratio of recurrence versus second malignancy for related death was 0.59 (95% confidence interval: 0.50-0.70) at 5 years and 0.61 (95% confidence interval: 0.52-0.72) at 10 years. Conclusion It appears that patients undergoing complete resection of thymoma have a higher incidence of a second malignancy and a greater related mortality rate than a recurrence of thymoma. A multiinstitutional database is required to more rigorously evaluate both risks and to confirm our results.

Anterior mediastinal tissue volume is correlated with antiacetylcholine receptor antibody level in myasthenia gravis.

OBJECTIVES: Extended thymectomy is a treatment option for myasthenia gravis (MG), but the surgical indications are controversial. Pathologic features of the thymus can be used to predict surgical outcomes, but there is no reliable method for evaluating these characteristics preoperatively. The purpose of this study was to determine whether anterior mediastinal tissue volume, as measured via 3-dimensional computed tomography (3DCT) volumetry, correlates with serum anti-acetylcholine receptor antibody (AChRAb) levels in patients undergoing thymectomy for myasthenia gravis. Therefore, we investigated the relationships among anterior mediastinal tissue volume determined by 3DCT volumetry and AChRAb levels. METHODS: The subjects were 28 patients who underwent extended thymectomy and were enrolled retrospectively. We measured volume of the anterior mediastinum and calculated the volumes of more than -30 Hounsfield units (V-30) by using 3DCT volumetry and compared them with perioperative AChRAb levels. The significance of their volumes in MG was examined by comparison with 53 patients without MG. RESULTS: V-30 values were related to age and were significantly greater in patients with MG than in patients without MG (P < .001). V-30 values were correlated positively with preoperative AChRAb levels (ρ = 0.505, P = .006) and inversely with the post/preoperative AChRAb ratio (ρ = -0.453, P = .018). The histologic nonadipose tissue ratio was correlated with the V-30/volume of the anterior mediastinum (ρ = 0.700, P < .001). CONCLUSIONS: This method for evaluation of the anterior mediastinal tissue volume and AChRAb production may be helpful in establishing a treatment plan for MG.

JLCS medical practice guidelines for thymic tumors: summary of recommendations.

The Guideline Committee of the Japan Lung Cancer Society (JLCS) for Thymic Tumors published the Medical Practice Guideline for Thymic Tumors in Japanese as Chapter 3 of the Medical Practice Guidelines for Lung Cancers according to evidence-based medicine in December 2016. This medical practice guideline is the first for thymic epithelial tumors in Japan, and comprises a set of recommendations covering clinical diagnosis, treatment and pathological diagnosis. Thymic epithelial tumors include thymoma, thymic carcinoma and thymic neuroendocrine tumor. The recommendations for clinical diagnosis concern detection of the symptoms, blood and serum tests according to clinical presentation, essential imaging for differential diagnosis and staging, and the necessity and methods of definitive diagnosis. The recommendations for treatment are dependent on tumor stage and recurrence status, and the treatment modalities included surgery, radiation therapy, chemotherapy and multimodality therapy. Those for pathological diagnosis deal with the handing methods of resected specimen and essential reporting contents for pathological diagnosis. Since data from large-scale analyses or clinical studies of thymic epithelial tumor are limited due to its low prevalence, the relevant recommendations and grading were based on available reported evidence and expert opinions as well as diagnostic methods and treatments commonly used in Japan. This report summarizes the recommendations concerning each topic addressed by this JLCS guideline for thymic tumors.

Three-dimensional imaging for thoracoscopic resection of complex lung anomalies.

BACKGROUND: Building surgical strategies for complex lung anomalies such as congenital pulmonary venolobar syndrome is difficult because of their rarity and variance. Using three-dimensional computed tomography (3D-CT), we can determine strategies safely. We describe a 27-year-old man with multifocal pulmonary malformations who underwent video-assisted thoracoscopic surgery (VATS) using 3D-CT. CASE PRESENTATION: A 27-year-old man presented with hemoptysis associated with complex pulmonary malformations, including a triple-arched vein connecting the superior and inferior pulmonary veins with partial drainage into the inferior vena cava, a systemic and numerous arterial supply to the right lower lobe from the abdominal aorta, abnormal lobulation, and a tracheal bronchus in the right lung. Preoperative simulation using 3D-CT helped to determine the optimal surgical strategy, allowing for successful and safe completion of semi-emergent middle and lower bilobectomy via minimally invasive VATS. CONCLUSIONS: Preoperative simulation using 3D-CT helped to determine the optimal surgical strategy, allowing for successful and safe completion of surgery even in a complex case.

Surgery of a nocardia lung abscess presenting as a tension pyopneumothorax.

While some cases of nocardial pneumonia develop secondary empyema, tension pyopneumothorax is a very rare and lethal complication. A 74-year-old man who exhibited thrombocytopenia during steroid therapy for autoimmune hepatitis, presented to our department with a nocardial tension pyopneumothorax. He underwent a left lower lobectomy after chest drainage, and was discharged without any complication other than reoperation to remove a postoperative hematoma.

Efficacy of Ramelteon for delirium after lung cancer surgery.

OBJECTIVES: The aim of the study was to evaluate the feasibility of Ramelteon for the prevention of delirium after lung cancer surgery in elderly patients. METHODS: Medical records of patients over 70 years old, who underwent anatomical pulmonary resection for lung cancer at our institution from January 2013 to December 2015, were reviewed. Patients treated in 2013 and 2014 were used as a control group. Ramelteon was administered daily for 7 days after surgery. The incidence of delirium was determined based on the Intensive Care Delirium Screening Checklist (ICDSC). Scores of ≥4 and 1-3 points were used for the diagnoses of delirium and a pre-delirious state, respectively. RESULTS: There were 24 patients in the Ramelteon group and 58 patients in the control group. ICDSC scores of ≥4 points were found for no patients in the Ramelteon group and 5 (9%) in the control group, whereas 21 (88%) and 49 (85%) patients, in the respective groups, had ICDSC scores of 0 points. The average incidence of events, associated with delirium, showed a trend of being lower in the Ramelteon group (0.25 ± 0.74 vs 1.58 ± 4.93, P = 0.061), and all events in the Ramelteon group occurred on the day of surgery. Thus, only one day was required for complete recovery from delirium in the Ramelteon group, whereas 8 days were needed in the control group. The peak delirious state occurred after 5 days in the control group. CONCLUSIONS: Ramelteon is likely to reduce the incidence and intensity of delirium after surgery for lung cancer in elderly patients.

Completion lobectomy after radical segmentectomy for pulmonary malignancies.

OBJECTIVE: Completion lobectomy after radical segmentectomy is relatively rare, with no systematic evaluation of this challenging procedure. We aimed to clarify the details of this operation performed in 3 Japanese institutions. METHODS: Completion lobectomy after segmentectomy in the same lobe was performed in 11 patients (9 lung cancers and 2 metastatic lung tumors) between 2007 and 2013. Surgical outcomes were analyzed retrospectively. RESULTS: The 11 patients accounted for 1.37% of the 805 segmentectomies performed in the 3 institutions. The reasons for completion lobectomy were postoperative complications in the remaining lobe (n = 3), positive pathological lymph node metastasis found by permanent section (n = 3), and malignancy in the remaining lobe (n = 5). The patients were divided into two groups according the interval between segmentectomy and completion lobectomy: group A (3-35 days, n = 5) and group B (56-1470 days, n = 6). There was a tendency for more severe adhesions around the hilum (p = 0.061) in group B, resulting in increased operative bleeding (p = 0.055), more usage of fibrin glue (p = 0.080), and significantly longer operative time (p = 0.036). Injury to the pulmonary arteries was experienced only in group B (3/6 cases). There was no operation-related mortality. CONCLUSIONS: Completion lobectomy may become more difficult approximately 5 weeks after segmentectomy, due to severe adhesions, but it can be performed safely with careful manipulation.

Successful resection of recurrent mediastinal liposarcoma using preoperative evaluation of organ invasion by four-dimensional computed tomography.

We report the case of a 64-year-old woman with recurrent mediastinal dedifferentiated liposarcoma. She had undergone surgical resection twice. Subsequently, on regular follow-up visits, chest computed tomography demonstrated a third local recurrence of the tumor with invasion into adjacent intrathoracic organs. Adhesion of the heart to the anterior chest wall through a pericardial defect that had been inadvertently created at the second operation was suspected. We decided to use a thoracoabdominal approach with four-dimensional computed tomography (4DCT) for preoperative guidance. The patient had also undergone MRI; however, the result was equivocal regarding adhesion of intrathoracic organs. The use of 4DCT enabled successful en bloc resection of the tumor. Results of the pathology examination showed complete resection of a dedifferentiated liposarcoma. The patient's postoperative course was uneventful, and she was discharged on postoperative day 19.

Postoperative pulmonary function and complications in living-donor lobectomy.

BACKGROUND: Successful living-donor lobar lung transplantation largely depends on the donor's outcome. Because surgical skills and peri-operative management have evolved over time, this study evaluated the recent outcomes of donor lobectomies. METHODS: Between 2008 and 2014, 48 consecutive living-donor lobar lung transplantations with 85 donor lobectomies were performed at Kyoto University. All donors were prospectively followed up regularly until 1 year after surgery. RESULTS: Right and left lower lobectomies were performed in 49 and 36 donors, respectively. Pulmonary arterial branches were sacrificed at equal frequency in both lobectomies, whereas pulmonary arterioplasty was only performed in left lower lobectomy (n = 9). All donors were discharged after the lobectomies, and none died during follow-up. Post-operative complications occurred in 24 donors (28%) overall, without a significant difference between donor sides. Intraoperative complications were found in 2 donors. Early and late post-operative complications were noted in 17 and 6 donors, respectively. Pneumothorax, pleuritis, and pleural effusion were the most frequent. Post-operative pulmonary function sequentially recovered more than expected and was not significantly affected by the sacrifice of pulmonary arterial branches during lobectomy. By contrast, pulmonary function at 1 year after donor lobectomy in the donors who had peri-operative complications was significantly lower than that in the donors who did not, although even post-operative pulmonary function in the donors with peri-operative complications still recovered more than expected. CONCLUSIONS: Living-donor lobectomies have been safely performed in recent decades with low morbidities and without mortality.