Real-world data on efficacy/safety and economic impact of nivolumab administered every 2 and 4 weeks among Japanese patients

AIM

A new treatment interval for nivolumab administration at 480 mg every 4 weeks, in addition to 240 mg every 2 weeks, was approved in Japan in 2020. Using model-based evaluation, it was speculated that the effects or safety of nivolumab do not differ between the two treatment intervals; however, real-world data on nivolumab efficacy, safety, and economic impact are lacking. Accordingly, we aimed to examine the effects of nivolumab treatment intervals (2 weeks vs. 4 weeks) in terms of efficacy, safety, and economic impact in Japanese patients with cancer.

METHODS

We retrospectively analyzed 126 patients treated with nivolumab. The patients were divided into two groups depending on whether they received nivolumab at 240 mg every 2 weeks (2-week group) or 480 mg every 4 weeks (4-week group).

RESULTS

Efficacy results found no significant difference between the 4- and 2-week groups considering median overall survival (p = 0.70) and median progression-free survival (p = 0.57). The incidence of any grade and ≥  grade 3 immune-related adverse events did not differ between the 4-week and 2-week groups (any grade, p = 0.13; ≥  grade 3, p = 0.36). Excluding drug costs, the 4-week group had significantly lower medical costs than the 2-week group (2-week vs. 4-week: mean, 94,659 JPY [679.0 USD] vs. 58,737 JPY [421.3 USD]; p < 0.05).

CONCLUSION

Collectively, our findings suggest that nivolumab 480 mg every 4 weeks may be more effective than nivolumab 240 mg every 2 weeks in terms of economic impact.

Eosinophil may be a predictor of immune-related adverse events induced by different immune checkpoint inhibitor types: A retrospective multidisciplinary study

BACKGROUND

Immune checkpoint inhibitors (ICIs) can cause severe immune-related adverse events (irAEs). However, biomarkers for irAEs common to different types of ICIs and cancers have not been reported. This study examined whether eosinophils can be used as a predictor of irAEs.

METHODS

Six hundred fourteen patients with cancer (esophageal, gastric, head and neck, lung, melanoma, renal cell, urothelial, and other cancer) received anti-PD-1, anti-PD-L1, or anti-CTLA-4 plus anti-PD-1 therapy. The patients were divided into two groups depending on whether they experienced irAEs (irAE group) or not (non-irAE group). Eosinophils were examined before the two-course treatment.

RESULTS

Patients in the irAE group who received anti-PD-1 or anti-CTLA-4 plus anti-PD-1 therapy had higher eosinophils before the two-course treatment than those in the non-irAE group (p < 0.05). The eosinophils in the anti-PD-L1 therapy group tended to increase in the irAE group. Furthermore, eosinophils in gastric, head and neck, lung, melanoma, renal, and urothelial cancers were significantly higher in the irAE group than in the non-irAE group (p < 0.05). The optimal cutoff value for eosinophils against irAEs was 3.0% (area under the curve = 0.668). In multivariate analyses, eosinophils of ≥3.0% were an independent factor for irAEs (odds ratio: 2.57, 95% CI: 1.79-3.67).

CONCLUSION

An increased eosinophil before the two-course treatment may be a predictor of irAEs in various cancers treated with different ICIs.

Heat-stable spores of carotenoid-producing Bacillus marisflavi and non-pigmented Bacillus subtilis cooperatively promote growth, quality, and gut microbiota of white-leg shrimp

We evaluated the benefits of heat-stable carotenoid-producing Bacillus marisflavi SH8 spores individually and in combination with non-pigmented Bacillus subtilis SH23 spores on growth, colour change, nutritional content, innate immunity, and gut microbiota of white-leg shrimp. White-leg shrimp (Litopenaeus vannamei; n = 30 per tank; 2 tanks per group) were provided feed without (control group) or with SH8, SH23, or mixed spores (total, 1 × 106 cfu/g pellet) for 28 d. The SH8 and SH8-23 combination groups had significantly higher specific growth rates (9.6 and 11.0%), improved red-colour score (4 scores), astaxanthin concentration (1.8- and 2.3-fold), lipid contents (30 and 50%), and superoxidase dismutase activity (8.5 and 12.3%) than that of the control group. Analysis of shrimp's gut microbiome using 16S rRNA metagenome sequencing revealed increased abundance of four useful species and reduced abundance of four harmful species in the combination group than in the control group. Heat-stable Bacillus spore combination improved growth parameters, nutrient content, red-colour score, live counts, and abundance of useful bacteria in the gut of L. vannamei. This is the first study to show the benefits of combining highly heat-stable pigmented and non-pigmented Bacillus spores and their possible mechanisms in a shrimp model.

Thoracoscopic Anatomical Sublobar Resection Including Subsegmentectomy for Non-Small Cell Lung Cancer

BACKGROUND

Among anatomical sublobar resection techniques for non-small cell lung cancer (NSCLC), the clinical benefit of subsegmentectomy remains unclear. We investigated whether anatomical sublobar resection including subsegmentectomy-segmental resection with subsegmental additional resection or subsegmental resection alone-is an effective and feasible surgical procedure for NSCLC.

METHODS

We retrospectively reviewed data of 285 patients with clinical stage I NSCLC who underwent anatomical sublobar resection at our institution from January 2013 to March 2021 and compared surgical outcomes between patients who underwent anatomical sublobar resection including (IS; n = 50) and excluding (ES; n = 235) subsegmentectomy.

RESULTS

No significant intergroup differences were noted in terms of age, sex, smoking, comorbidities, tumor size or location, consolidation tumor ratio, and preoperative pulmonary function. The IS group had more preoperative computed tomography-guided markings (34 vs. 15%; p = .004) and smaller resected lung volumes converted to the total subsegment number [3 (2-4) vs. 3 (3-6); p = .02] than the ES group. No significant differences in margin distance [mm, 20 (15-20) vs. 20 (20-20); p = .93], readmission rate (2% vs. 3%; p > .99), and intraoperative (8% vs. 7%; p = .77) or postoperative (8% vs. 10%; p = .80) complication rates were observed, and the 5-year local recurrence-free survival (91% vs. 90%; p = .92) or postoperative pulmonary function change were comparable between both groups.

CONCLUSIONS

Although further investigations are required, anatomical sublobar resection including subsegmentectomy for clinical stage I NSCLC could be an acceptable therapeutic option.

Prognostic value of systemic inflammatory markers and the nutrition status in thymic epithelial tumors with complete resection

Background

Recent studies have shown that several systemic inflammatory markers and the nutrition status, including the neutrophil‐to‐lymphocyte ratio (NLR), monocyte‐to‐lymphocyte ratio (MLR), platelet‐to‐lymphocyte ratio (PLR), and prognostic nutritional index (PNI), are useful prognostic factors in several malignant tumors. The present study explored the prognostic value of the NLR, MLR, PLR, and PNI in thymic epithelial tumor (TET) patients who underwent complete resection.

Methods

A total of 158 TET patients who underwent complete resection were involved in the analysis. Their NLR, MLR, PLR, and PNI values were obtained from a blood examination within one month before the initiation of treatment. A receiver operating characteristic curve analysis was conducted to determine the optimal cutoff values.

Results

The enrolled patients were stratified by cutoffs of 4.35 for the NLR, 0.22 for the MLR, 130.18 for the PLR, and 44.02 for the PNI. A univariate analysis revealed that high‐grade malignant TET, including type B2 and B3 thymoma, thymic carcinoma, and thymic neuroendocrine tumor; an advanced Masaoka stage; a high NLR; a high MLR; and a low PNI were significant predictors of a poor disease‐free survival (DFS). A multivariate analysis confirmed that an advanced Masaoka stage (HR = 5.5557, p = 0.0007) and a high MLR (HR = 3.3371, p = 0.0264) were independent predictors of a poor DFS.

Conclusions

Our study demonstrated that the pretreatment MLR was an independent predictor of the DFS in patients with TETs who underwent complete resection.

Hemoptysis after coil embolization for pulmonary arteriovenous malformation: Histopathological confirmation of bronchial epithelium extension

Coil embolization is widely performed for pulmonary arteriovenous malformations (PAVMs). We describe herein 2 cases of hemoptysis during long-term follow-up after coil embolization for PAVMs. For both cases, lobectomy was performed and histopathological examinations revealed chronic inflammation and bronchial epithelium extension into the sac of the PAVM. In addition, we performed a systematic review of previous reports of hemoptysis after embolization for PAVMs.

AB0095 CHARACTERISTICS OF TUMOR NECROSIS FACTOR-ALPHA AND INTERLEUKIN-6-INDUCED OSTEOCLASTS IN PERIPHERAL BLOOD AND BONE TISSUE FROM PATIENTS WITH RHEUMATOID ARTHRITIS

Background

We have previously reported that stimulation of mouse bone marrow–derived macrophages with tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) induces differentiation of osteoclast-like cells having bone resorption ability1. Recently, we have shown that the combination of TNF-α and IL-6 can induce osteoclasts from human peripheral blood mononuclear cells (PBMCs) via RANKL-independent pathways, and that there are functional differences between TNF-α and IL-6-induced osteoclasts (T6-OCs) and RANKL-induced, conventional osteoclasts (cOCs). In particular, the number of T6-OCs differentiated from PBMCs in patients with rheumatoid arthritis (RA) positively correlated with the modified total Sharp score (mTSS)2. On the other hands, no such correlation was observed between the number of cOCs from RA and mTSS.

Objectives

Objectives of this study were to compare the differentiational potential into T6-OCs of PBMCs from RA patients with those from healthy donors, to clarify mRNA and protein expressions of T6-OCs derived from PBMCs from patients with RA, and to identify tartrate resistant acid phosphatase (TRACP) positive multinuclear cells with the same characters as T6-OCs histologically in the sub-chondral bone tissues from patients with RA and osteoarthritis (OA).

Methods

PBMCs and CD14+ monocytes derived from RA patients and healthy volunteers were stimulated with TNF-α and IL-6 or RANKL. Real-time quantitative PCR and immunofluorescence staining were used to measure expression levels of osteoclast-associated mRNA and protein. Consecutive sections of the proximal tibial bone tissue from patients with RA and OA (n=6 each) were stained by TRACP, and analyzed expression levels of osteoclast-associated molecules by immunohistochemistry.

Results

The number of T6-OCs differentiated from PBMCs in RA patients was significantly increased compared to that in healthy volunteers. Expression levels of RANK mRNA and protein were clearly up-regulated in cOCs differentiated from CD14+ monocytes and were down-regulated in T6-OCs. In contrast, expression levels of MMP-3 mRNA and protein were obviously up-regulated in T6-OCs and down-regulated in cOCs. Therefore, we believe T6-OCs and cOCs were differently identified on bone tissue as TRACP+RANK-/MMP-3+ cells and TRACP+RANK+/MMP-3- cells, respectively. The numbers of TRACP+ osteoclasts in subchondral cancellous bone were significantly increased in RA patients compared to those in OA patients. Interestingly, numerous TRACP+/RANK-/MMP-3+ osteoclasts were present in the subchondral bone from patients with RA, on the other hands, no such cells observed in OA patients.

Conclusion

The PBMCs of RA patients have definitely increased differentiation capacity into T6-OCs, which have potential of degrading chondral tissue. Additionally, cells having same characteristics with T6-OCs are observed in subchondral bone of patients with RA. These results suggest that novel T6-OCs may be involved in the pathogenic mechanisms of inflammatory bone destruction in patients with RA.

References

[1]Yokota K, Sato K, Miyazaki T, Kitaura H, Kayama H, Miyoshi F, Araki Y, Akiyama Y, Takeda K, Mimura T. Combination of Tumor Necrosis Factor α and Interleukin-6 Induces Mouse Osteoclast-like Cells With Bone Resorption Activity Both in Vitro and In Vivo. Arthritis & Rheumatology Jan;66(1):121-9, 2014.

[2]Yokota K, Sato K, Miyazaki T, Aizaki Y, Tanaka S, Sekikawa M, Kozu N, Kadono Y, Oda H, Mimura T. Characterization and Function of Tumor Necrosis Factor alpha and Interleukin-6-Induced Osteoclasts in Rheumatoid Arthritis. Arthritis & Rheumatology Jul;73(7):1145-1154, 2021.

Acknowledgements

We are grateful to H. Kajiyama and Y. Araki (Saitama Medical University) for helpful discussion.

Disclosure of Interests

None declared

A large intrathoracic goiter with tracheal stenosis: Complete resection using a robot-assisted thoracoscopic approach

Growing intrathoracic goiters may compress surrounding organs and deteriorate the cardiopulmonary function. Treating such cases requires carefully considering how to maintain oxygenation and resect the tumor with minimal invasiveness without complications. We herein report a surgically resected case of a large intrathoracic goiter‐compressed trachea extending from the right lower pole of the thyroid gland to the carina. We secured the airway by intubation preparing for extracorporeal membrane oxygenation and successfully performed surgical complete resection using a robot‐assisted thoracoscopic and cervical approach. Intrathoracic goiter is a tumor with abundant neovascularity, and the right vagus nerve is displaced in the thoracic cavity, but a robot‐assisted thoracoscopic approach using CO₂ insufflation improved visualization at the narrow apex area of the thoracic cavity. Robot‐assisted thoracoscopic surgery is a useful surgical procedure enabling safe and minimally invasive surgery without recurrent laryngeal nerve palsy or tracheal injury for intrathoracic giant goiters extending into the thoracic cavity.

Comparison of the efficacy of novel two covering methods for spontaneous pneumothorax: a multi-institutional study

OBJECTIVES

The postoperative recurrence rate after thoracoscopic bullectomy for primary spontaneous pneumothorax (PSP) is not satisfactory. This retrospective study was conducted to elucidate an effective technique for improving the postoperative recurrence rate.

METHODS

The present study included 373 patients who underwent thoracoscopic bullectomy for PSP at three hospitals from January 2013 to May 2020. We compared the recurrence rate according to two methods that were used to cover the staple line after thoracoscopic bullectomy. Group A (146 patients) was treated with an absorbable polyglycolic acid (PGA) sheet plus fibrin glue and oxidised regenerated cellulose (ORC). Group B (227 patients) was treated with ORC alone.

RESULTS

There was no significant difference in preoperative characteristics of the patients. The postoperative recurrence rate of pneumothorax was 3.4% (5/146) in Group A and 17.2% (39/227) in Group B, respectively. Among 23 patients (Group A, n=3 and Group B, n=20) who received reoperation for recurrent pneumothorax, the site of recurrence was around the stapler line of the first operation in 1 of 5 (20%) patients in Group A and 28 of 39 (71.8%) patients in Group B. The 1-year recurrence-free rate was 97.4% (median follow-up period, 73 days (range, 2-3952 days)) in Group A and 80.9% (median follow-up period, 71 days (range 2-2648 days)) in Group B.

CONCLUSIONS

Coverage with a PGA sheet may prevent the postoperative recurrence of PSP. A large-scale prospective randomised study should be conducted to clarify the most effective treatment for PSP.

Complex video-assisted thoracoscopic surgery lobectomy for locally advanced lung cancer: a prospective feasibility study

PURPOSE

The limitations regarding indications for video-assisted thoracoscopic surgery lobectomy requiring complex surgery remain unclear. A prospective cohort study was conducted to elucidate the safety and feasibility of complex thoracoscopic lobectomy for patients with locally advanced non-small-cell lung cancer.

METHODS

We planned to enroll patients who were suspected of needing thoracoscopic lobectomy or more with complex surgery, including tracheo-bronchoplasty, pulmonary arterioplasty, and combined resection of adjacent organs. Between February 2016 and January 2019, 28 consecutive patients were prospectively enrolled.

RESULTS

After excluding 1 patient due to disease progression, 27 patients were included in this study. Three patients underwent thoracoscopic lobectomy without complex surgery. Of the remaining 24 patients, complex thoracoscopic lobectomy was successfully completed in 21 (88%), and the 3 conversions were due to surgery for the great vessels. All 27 patients achieved complete resection. Six patients (22%) suffered grade 2 complications, and the in-hospital, 30-day, and 90-day mortality rates were all 0%. At a median follow-up time of 900 days, the 3-year overall and disease-free survival rates were 75% and 54%, respectively.

CONCLUSIONS

Complex thoracoscopic lobectomy was shown to be safe and feasible in select patients with locally advanced non-small-cell lung cancer excluding invasion to the great vessels.

CLINICAL REGISTRATION NUMBER

University Hospital Medical Information Network Clinical Trials Registry, 000,019,441 (JAPAN). Institutional Review Board number: 46-15-0003 (accepted at September 7, 2015).

A single-center analysis of 71 patients with thymic carcinoma: the chronological changes in the surgical procedure and prognosis

Background

Effective treatments for thymic carcinoma (TC) have not been established due to its rarity and the prognosis has not yet been improved. In the present study, data of patients who underwent treatment for TC at our single institution were retrospectively reviewed to investigate the chronological changes in the clinical characteristics, surgical procedure, and prognosis.

Methods

A total of 71 patients were included in this study. To investigate the chronological changes, the patients were divided into two groups at January 2009, when minimally invasive surgery (MIS) for thymic epithelial tumors (TETs) was introduced.

Results

Among the 71 TC patients, 24 patients underwent surgery through December 2008 (earlier period), and 21 underwent surgery from January 2009 (later period). The patients in the later group were more likely to be diagnosed by chest computed tomography (CT) scan without subjective symptom. The rates of MIS and complete resection were significantly higher and the number of the patients at the early stage were significantly greater in the later group. The 5-year overall survival (OS) rate of the patients who underwent surgery at earlier and later groups were 58.7% and 92.8% respectively (P<0.01).

Conclusions

The prognosis of TC has improved over time, thanks to early detection by CT screening and complete surgical resection.

Examination on the necessity of pericardial fat tissue resection in extended thymectomy for myasthenia gravis

Background

Extended thymectomy with pericardial fat tissue resection has been a mainstay in the treatment for myasthenia gravies (MG), but few studies have examined the necessity of the pericardial fat tissue resection in extended thymectomy.

Methods

We pathologically examined the distribution of germinal centers in the resected thymus including the thymus-surrounding fat tissue. Patients who underwent extended thymectomy using subxiphoid thoracoscopy for generalized MG or thymoma with anti-acetylcholine receptor antibody (anti-AchR Ab) positivity from March 2015 to January 2021 were included in this study.

Results

A total of 20 patients underwent extended thymectomy (generalized nonthymomatous MG, n=5; generalized MG with thymoma, n=6; thymoma with anti-AchR Ab positivity, n=9). The resected specimens were divided to 6 parts and were pathologically examined to investigate the distribution of the geminal centers in all lesions. The number and distribution of germinal centers in the thymus varied depending on the patient, and no germinal centers were identified in the right or left pericardial fat tissues.

Conclusions

It is necessary to resect the pericardial fat tissue in patients whose preoperative images show the presence of pericardial fat tissue hyperplasia or ectopic thymoma. However, extensive pericardial fat tissue resection might not be necessary for all MG patients who undergo extended thymectomy with opening of the bilateral pleural by video-assisted or robot-assisted thoracoscopic surgery (RATS) via a subxiphoid approach.

Type A thymoma with simultaneous solitary intrapulmonary metastasis: A case report

A 79‐year‐old woman was referred to our facility because of an abnormal chest shadow. Chest computed tomography (CT) showed a solitary right middle lung nodule with a maximum diameter of 3 mm and anterior mediastinal nodule with a maximum diameter of 21 mm. The lung nodule was suspected of being a primary lung cancer rather than a metastatic tumor because there were no primary malignant tumors, apart from an anterior mediastinal tumor visible on diagnostic imaging, including F¹⁸ fluorodeoxyglucose‐positron emission tomography, and a solitary lung nodule. Partial lung resection by video‐assisted thoracoscopic surgery (VATS) was performed, and the intraoperative frozen section of the tumor tissue resulted in a diagnosis of carcinoid tumor. As a result, right middle lobectomy by VATS was performed. The final histological diagnosis of the permanent specimen was intrapulmonary type A thymoma. VATS thymectomy was performed three months later. The histological diagnosis was type A thymoma with intrapulmonary metastasis (Masaoka stage IVb). Additional therapy was not performed because complete resection was achieved. Follow‐up CT was performed once every six months after the operation. The patient has been followed up for one year without any further recurrence.

The usefulness of fluorodeoxyglucose-positron emission tomography as a preoperative diagnostic tool for thymic epithelial tumors

Background

To investigate the usefulness of ¹⁸F-fluorodeoxy glucose-positron emission tomography (¹⁸F-FDG PET) for the preoperative imaging diagnosis of malignant grade in thymic epithelial tumors (TETs) and the correlation between the maximum standardized uptake value (SUVmax) and tumor size in TETs.

Methods

We retrospectively investigated 51 patients with TETs performed ¹⁸F-FDG PET. The SUVmax was compared between thymic carcinomas and thymomas. We also evaluated the difference in the SUVmax limited to small TETs. In addition, the correlation between the SUVmax and the tumor size was evaluated.

Results

The mean SUVmax of thymic carcinomas (n=12) and thymomas (n=39) was 5.71±2.6 and 3.08±1.4, respectively. The SUVmax of thymic carcinomas was significantly higher than that of thymomas (P<0.001). The mean SUVmax of these small thymic carcinomas (n=3) and thymomas (n=13) was 2.97±0.24 and 1.79±0.47, respectively. The SUVmax of the small thymic carcinomas was significantly higher than that of the thymomas (P=0.001). We found a positive correlation between the SUVmax and the maximum tumor size of TETs (correlation coefficient: 0.632, P<0.001).

Conclusions

¹⁸F-FDG PET might be useful for evaluating the preoperative malignancy of TETs. Of note, the maximum tumor size should be considered when performing assessments by ¹⁸F-FDG PET.

Extended Bronchoplasty Anastomosed between the Left Main and the Superior Segmental Bronchi for Locally Advanced Left Upper Lobe Lung Cancer with Invasion of the Basal Segment

We report a case of extended bronchoplasty in which anastomosis between the left main and the superior segmental bronchi with resection of the left upper lobe and basal segment was required to avoid pneumonectomy for locally advanced lung cancer. The main tumor located at the left upper lobe invaded the basal segment, and involved both the basal pulmonary artery and left secondary carina. Regarding anastomosis, the bronchi were cut in a deep wedge shape and a wall flap was made by part of the lower lobar bronchus. The patient’s postoperative course was uneventful and he has been alive without recurrence for more than 3 years after surgery.

A simple and reliable method to preoperatively detect a common trunk of the left pulmonary vein

Background

It is difficult to detect a common trunk of the left pulmonary vein (PV) preoperatively, which may cause intraoperative accidental complications. The purpose of this study is to establish a simple and reliable method of detecting a common trunk in preoperative computed tomography (CT) images.

Methods

A total of 428 patients who underwent thin-section CT preoperatively for left lung cancer at 4 institutions were reviewed. The characteristic findings of a common trunk in the axial view were considered by confirming the preoperative CT findings of cases that had been verified to have a common trunk based on intraoperative findings. The CT images were reviewed independently by two evaluators.

Results

We found that the distance between the mediastinal side of the left lower bronchus and the junction of two left PVs was extremely short in the cases with a common trunk in the axial view. In a typical case, the axial section of the bronchus is close to the junction. Of the 416 patients that were evaluable among the 428 total patients, 26 (6.3%) were diagnosed as having a common trunk by both evaluators, and the diagnosis was coincident in 413 patients (99.2%). We were able to evaluate the surgical videos of 16 of the 26 patients, and a common trunk was confirmed in 15 patients (94%).

Conclusions

We established a simple and reliable method of detecting a common trunk of the left PV in the axial view on chest CT that was routinely performed prior to lung cancer surgery.

Pericardial immunoglobulin G4-related inflammatory pseudotumor after right upper lobectomy for lung cancer

A 75‐year‐old woman underwent thoracoscopic right upper lobectomy for lung cancer. A histopathological examination showed adenocarcinoma, pT1aN0M0 stage IA1. At six months after surgery, chest computed tomography (CT) revealed pericardial nodules that had not been detected before pulmonary resection. Postoperative CT performed two months later revealed that the nodules were growing and F¹⁸ fluorodeoxyglucose‐positron emission tomography showed a maximum standardized uptake of 9.87. Blood tests revealed no elevated tumor markers, with the exception of a mildly elevated interleukin‐2. Based on the above results, thoracoscopic biopsy was performed due to the suspected recurrence of lung cancer or malignant lymphoma. The histopathological examination of the nodule revealed immunoglobulin G4 (IgG4)‐related inflammatory pseudotumor. The serum IgG4 levels were elevated (358 mg/dL, normal: 4.5–117.0 mg/dL). No additional treatment was required because all nodules were observed to have disappeared naturally on a follow‐up CT scan performed two months after the surgical biopsy. The patient has been followed‐up for two years without recurrence.

Key points

Significant findings of the study

We report a case of pericardial immunoglobulin G4‐related inflammatory pseudotumor that appeared after right upper lobectomy for lung cancer, and which naturally disappeared without any treatment.

What this study adds

There was an immunoglobulin G4‐related inflammatory pseudotumor which appeared as multiple nodules in the pericardial space, and this should be kept in mind when considering the differential diagnosis of intrapericardial nodules.

Long-term survivor of pulmonary combined large cell neuroendocrine carcinoma treated with nivolumab

Several authors have previously reported that patients with pulmonary combined large cell neuroendocrine cancer ( LCNEC) have a poor prognosis and there is no consensus on the treatment strategy for combined LCNEC as well as LCNEC. Here, we report the case of a long‐term survivor with pulmonary combined LCNEC. The patient was a 60‐year‐old man who underwent thoracoscopic right lower lobectomy. The final histopathology and staging of the tumor showed LCNEC combined with squamous cell carcinoma and T2aN0M0 stage IB. Multimodality treatments including chemotherapy, radiotherapy and surgery for several recurrences were performed after the pulmonary surgery. After immune checkpoint inhibitor (ICI) therapy with nivolumab, all the metastatic lesions shrunk and a partial response was maintained at five years after the first surgery. In our case, ICI after multimodality therapy combining cytotoxic anticancer drugs and radiotherapy was effective in LCNEC with metachronous multiple metastases.

Key points

Significant findings of the study

Immune checkpoint inhibitor after multimodality therapy combining cytotoxic anticancer drugs and radiotherapy was effective in LCNEC with metachronous multiple metastases. The patient survived over five‐years after the first surgery.

What this study adds

Immune checkpoint inhibitor may be effective in some LCNEC patients.

EFFECT OF PREGNANCY ON LOWER LIMB LYMPHEDEMA IN PATIENTS TREATED WITH MULTISITE LYMPHATICOVENULAR ANASTOMOSES (MLVAS)

Lymphaticovenular anastomosis (LVA) using supermicrosurgical techniques is effective for treating and preventing progression of lymphedema. We analyzed the influence of pregnancy on LVA in five patients from a total 2179 LVA cases. Previous studies offer conflicting reports on whether pregnancy worsens pre-existing lymphedema. This is the first report on the influence of pregnancy on lower limb lymphedema previously treated by multisite LVA (mLVA). Five patients with primary (n=4) and secondary (n=1) lower leg lymphedema were analyzed for this study. Patient age ranged from 18 to 31 (average 22.6) years old with 4 right and 1 left extremities involved. Duration of symptoms ranged from one to 19 (average 7.4) years and the periods of compression therapy were from 1 to 19 years (6.6 years). Four patients had single pregnancies and one patient was multiparous with 3 pregnancies. Final follow-up ranged from 5.8 to 18 years (average 8.9 years) after the primary mLVA. All patients had normal pregnancy, birth, and no serious complications after surgeries. Following pregnancy three patients had complete functional recovery (limb volume reduction and no compression requirement), one with functional improvement (limb volume reduction but required compression), and one with no change in symptoms (not worse and continued need for compression). There were no occurrences of infection following pregnancy. Based on this case series, it is suggested that pregnancy does not worsen the pre-existing lymphedema in patients who had previously undergone mLVA. Further studies with larger number of patients are needed to confirm these results.

Mixed-type primary germ cell tumor of the mediastinum in a young adult male with a sudden life threatening condition: A case report

Primary germ cell tumors of the mediastinum are rare neoplasms. Above all, choriocarcinomas are highly aggressive with early haematogenous dissemination. Here, we report an extremely rare case of mixed‐type primary germ cell tumor of the mediastinum which occurred in a 26‐year‐old man with multiple metastases of the lung caused by choriocarcinoma components, with diffuse pulmonary hemorrhaging. The patient developed a sudden life threatening condition a few days after a needle biopsy.

Key points

Significant findings of the study: This was an extremely rare case of mixed‐type germ cell tumor in a young adult male who developed a sudden life threatening condition due to choriocarcinoma components just a few days after a needle biopsy.

What this study adds: Serious conditions may occur in patients with germ cell tumor containing choriocarcinoma components. At present, there is no other way to treat such patients than to promptly recognize complications and perform urgent multimodal intervention.

Hemothorax during miniaturized endoscopic combined intrarenal surgery under ureteroscope-assisted ultrasound-guided access

Introduction

Hemothorax is a rare but life‐threatening complication following mini‐endoscopic combined intrarenal surgery. Herein, we describe a patient with left staghorn kidney stone who presented with hemothorax following mini‐endoscopic combined intrarenal surgery under ureteroscope‐assisted ultrasound‐guided access.

Case presentation

A 47‐year‐old woman with left staghorn kidney stone underwent mini‐endoscopic combined intrarenal surgery, after which she developed shortness of breath. Chest radiography and computed tomography confirmed left hemothorax. Conservative management and left intercostal chest drainage were performed without improvement. Subsequently, video‐assisted thoracoscopic debridement was performed.

Conclusion

Hemothorax is a severe complication of mini‐endoscopic combined intrarenal surgery, which, regardless of accurate access through an ideal renal calyx under ureteroscope‐assisted ultrasound‐guided access, may lead to pleural injury. Refinement of the surgical technique and management after percutaneous nephrolithotomy is the key to avoiding life‐threatening situations.

Talc pleurodesis for secondary pneumothorax in elderly patients with persistent air leak

Background

We herein report the usefulness of two types of talc pleurodesis for secondary pneumothorax of elderly patients with persistent air leak who have severe pulmonary emphysema.

Methods

We assessed 17 elderly patients with persistent air leak who received talc pleurodesis for secondary pneumothorax from April 2013 to March 2017. Thoracoscopic talc poudrage (TTP) (n=11) was performed in patients whose general condition was thought to sufficiently stable to tolerate for general anesthesia. Talc slurry pleurodesis (TSP) (n=6) via a chest tube was performed in patients whose general condition was thought to be insufficiently stable to tolerate general anesthesia.

Results

The median drainage period after pleurodesis was 6 days in patients who received TTP and 12 days in patients who received TSP. Complications associated with talc pleurodesis included atrial fibrillation (n=1) in the thoracoscopic poudrage group, while the slurry pleurodesis group showed chest pain (n=2), asthmatic attack (n=1), and pneumonia (n=1). All patients who received thoracoscopic poudrage were able to leave the hospital after removal of the chest tube. Five of the six patients who received slurry pleurodesis were able to leave the hospital, but one of them died of acute exacerbation of interstitial pneumonia (IP) on the 45th day after pleurodesis. The success rate was 94% (16/17). There were no cases of recurrence during the observation period.

Conclusions

TTP was deemed likely to be safe and effective for patients able to tolerate general anesthesia. In patients with IP, especially those treated with steroids, the indication of talc pleurodesis should be cautiously considered.

Effect of pregnancy on lower limb lymphedema in patients treated with multisite lymphaticovenular anastomoses (MLVAS)

Lymphaticovenular anastomosis (LVA) using supermicrosurgical techniques is effective for treating and preventing progression of lymphedema. We analyzed the influence of pregnancy on LVA in five patients from a total 2179 LVA cases. Previous studies offer conflicting reports on whether pregnancy worsens pre-existing lymphedema. This is the first report on the influence of pregnancy on lower limb lymphedema previously treated by multisite LVA (mLVA). Five patients with primary (n=4) and secondary (n=1) lower leg lymphedema were analyzed for this study. Patient age ranged from 18 to 31 (average 22.6) years old with 4 right and 1 left extremities involved. Duration of symptoms ranged from one to 19 (average 7.4) years and the periods of compression therapy were from 1 to 19 years (6.6 years). Four patients had single pregnancies and one patient was multiparous with 3 pregnancies. Final follow-up ranged from 5.8 to 18 years (average 8.9 years) after the primary mLVA. All patients had normal pregnancy, birth, and no serious complications after surgeries. Following pregnancy three patients had complete functional recovery (limb volume reduction and no compression requirement), one with functional improvement (limb volume reduction but required compression), and one with no change in symptoms (not worse and continued need for compression). There were no occurrences of infection following pregnancy. Based on this case series, it is suggested that pregnancy does not worsen the pre-existing lymphedema in patients who had previously undergone mLVA. Further studies with larger number of patients are needed to confirm these results.

What are the risk factors for postoperative infections of third molar extraction surgery: A retrospective clinical study?

BACKGROUND

This study aimed to identify (1) the predilection site of postoperative infection after third molar extraction surgery, (2) risk factors associated with postoperative infection, and (3) the cause of the difference between delayed- and early-onset infections.

MATERIALS AND METHODS

This retrospective study included 1010 patients (396 male, 614 female) who had ≥1 third molars extracted (2407; 812 maxilla, 1595 mandible). The risk factors were classified as attributes, general health, anatomic, and operative. Outcome variables were delayed- and early-onset infections.

RESULTS

Postoperative infection was completely absent in the maxilla, and all infections occurred in the mandible, with a probability of 1.94% (31/1595). Bivariate analysis for postoperative infection showed depth of inclusion and intraoperative hemostatic treatment to be significantly associated with the development of infections. Bivariate analysis for delayed- and early-onset infections showed simultaneous extraction of the left and right mandibular third molars to be prominent risk factors.

CONCLUSIONS

Postoperative infection occurs mainly in the mandible, and that in the maxilla is very rare. The risk of postoperative infection in the mandible was found to be related to the depth of inclusion and intraoperative hemostatic treatment. Simultaneous extraction of the left and right mandibular third molars appear to increase the risk of delayed-onset postoperative infection.

Thymic inflammatory pseudotumor with multilocular thymic cyst caused by immunoglobulin G4-related disease

A 44-year-old man was referred to our hospital after an anterior mediastinal tumor was noted on computed tomography during follow-up observation after left testicular seminoma resection. Chest computed tomography revealed an enhanced mass measuring 33 x 16 x 15 mm at the anterior mediastinum. Chest magnetic resonance imaging revealed high signal intensity on T2-weighted imaging, and F¹⁸  fluorodeoxyglucose-positron emission tomography showed a maximum standardized uptake of 12.45. Laboratory tests revealed no elevated tumor markers, except for mildly elevated interleukin-2. Based on these results, complete resection was performed under suspicion of a malignant tumor, mediastinal metastasis of seminoma, or malignant lymphoma. An extended thymectomy with partial merger pericardial resection was performed using a subxiphoid approach. Small nodules and multiple thymic cysts were observed the thymus in addition to the main mass. Microscopic examination of the tumor revealed fibrosis, lymphocyte infiltration with lymphoid follicular hyperplasia, and hyperplasia of the thymus. Numerous immunoglobulin G4 (IgG4)-positive plasma cells were found on immunohistochemical staining. The ratio of IgG4 to total IgG was approximately 60%. We ultimately diagnosed the patient with a thymic inflammatory pseudotumor with multilocular cyst caused by IgG4-related disease.

Blastomatoid pulmonary carcinosarcoma: A rare case report and review of the literature

A 65‐year‐old never‐smoking woman presented to a local hospital, because an abnormal shadow was detected at the right lower lung field by annual chest X‐ray. Computed tomography (CT) revealed a 5‐cm tumor in segment 6 of her right lung and an enlarged subcarinal lymph node, suggesting metastasis. The lung tumor was diagnosed as adenocarcinoma by a CT‐guided percutaneous needle biopsy. She was referred to our hospital and underwent right lower lobectomy with lymph node dissection (ND2a‐2). A histopathological examination of the tumor showed a biphasic proliferation made of carcinomatous and sarcomatous components. The carcinomatous component consisted of glandular structures of atypical cells that possessed chromatin‐rich nuclear and clear cytoplasm, confirming high‐grade fetal adenocarcinoma. The sarcomatous component consisted of immature spindle cells that differentiated into chondrosarcoma. Immunohistochemically, the glandular structures expressed membranous beta‐catenin, and the ultimate diagnosis was blastomatoid variant of pulmonary carcinosarcoma. She received four courses of cisplatin plus vinorelbine as adjuvant chemotherapy and remained alive with neither recurrence nor distant metastasis at two and a half years after the operation. We experienced a rare case of blastomatoid pulmonary carcinoasarcoma.

Four immunohistochemical assays to measure the PD-L1 expression in malignant pleural mesothelioma

Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 pathway are expected to be a novel therapy for combating future increases in numbers of malignant pleural mesothelioma (MPM) patients. However, the PD-L1 expression, which is a predictor of the response to ICIs, is unclear in MPM. We studied the PD-L1 expression using four immunohistochemical assays (SP142, SP263, 28-8 and 22C3) in 32 MPM patients. The PD-L1 expression in tumor cells and immune cells was evaluated to clarify the rate of PD-L1 expression and the concordance among the four assays in MPM. The positivity rate of PD-L1 expression was 53.1% for SP142, 28.1% for SP263, 53.1% for 28-8, and 56.3% for 22C3. Nine cases were positive and 10 were negative for all assays. Discordance among the four assays was found in 13 cases. The concordance rates between SP142 and 22C3 and between 28-8 and 22C3 were the highest (84.4%). The concordance rates between SP263 and the other three assays were low (71.9% to 75.0%). The PD-L1 expression in MPM was almost equivalent for three of the assays. Given the cut-off values set in our study, these findings suggested that these assays, except for SP263, can be used for accurate PD-L1 immunostaining in MPM.

Use of ATP bioluminescence to survey the spread of aerosol and splatter during dental treatments

Aerosol and splatter produced during dental treatments (ultrasonic scaling and professional mechanical tooth cleaning) are potential sources of infection. Contamination patterns on the mask, goggles, chest and gowned right arm of operators, and on the goggles of patients before and after dental treatments were investigated using ATP bioluminescence analysis. Contamination on every surface tested increased significantly after dental treatment. Maximum contamination was found on the goggles of patients. Aerosol and splatter produced during dental treatments therefore have the potential to spread infection to operators and patients. ATP bioluminescence is a useful tool for monitoring surface contamination.

The correlation of urinary podocytes and podocalyxin with histological features of lupus nephritis

Objectives The objective of this study was to test the correlation of urinary podocyte number (U-Pod) and urinary podocalyxin levels (U-PCX) with histology of lupus nephritis. Methods This was an observational, cross-sectional study. Sixty-four patients were enrolled: 40 with lupus nephritis and 24 without lupus nephritis (12 lupus nephritis patients in complete remission and 12 systemic lupus erythematosus patients without lupus nephritis). Urine samples were collected before initiating treatment. U-Pod was determined by counting podocalyxin-positive cells, and U-PCX was measured by sandwich ELISA, normalized to urinary creatinine levels (U-Pod/Cr, U-PCX/Cr). Results Lupus nephritis patients showed significantly higher U-Pod/Cr and U-PCX/Cr compared with patients without lupus nephritis. U-Pod/Cr was high in proliferative lupus nephritis (class III±V/IV±V), especially in pure class IV (4.57 (2.02-16.75)), but low in pure class V (0.30 (0.00-0.71)). U-Pod/Cr showed a positive correlation with activity index ( r=0.50, P=0.0012) and was independently associated with cellular crescent formation. In contrast, U-PCX/Cr was high in both proliferative and membranous lupus nephritis. Receiver operating characteristic analysis revealed significant correlation of U-Pod/Cr with pure class IV, class IV±V and cellular crescent formation, and the combined values of U-Pod/Cr and U-PCX/Cr were shown to be associated with pure class V. Conclusions U-Pod/Cr and U-PCX/Cr correlate with histological features of lupus nephritis.

Intermolecular Interaction between Phosphatidylcholine and Sulfobetaine Lipid: A Combination of Lipids with Antiparallel Arranged Headgroup Charge

Intermolecular interactions between lipid molecules are important when designing lipid bilayer interfaces, which have many biomedical applications such as in drug delivery vehicles and biosensors. Phosphatidylcholine, a naturally occurring lipid, is the most common lipid found in organisms. Its chemical structure has a negatively charged phosphate linkage, adjacent to an ester linkage in a glycerol moiety, and a positively charged choline group, placed at the terminus of the molecule. Recently, several types of synthetic lipids that have headgroups with the opposite charge to that of phosphatidylcholine have emerged; that is, a positively charged ammonium group is present adjacent to the ester linkage in their glycerol moiety and a negatively charged group is placed at their terminus. These types of lipids constitute a new class of soft material. The aim of this study was to determine how such lipids, with antiparallel arranged headgroup charge, interact with naturally occurring phosphatidylcholines. We synthesized 1,2-dipalmitoyl-sn-glycero-3-sulfobetaine (DPSB) to represent a reversed-head lipid; 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) was used to represent a naturally occurring phospholipid. The intermolecular interaction between these lipids was investigated using surface pressure-area (π-A) isotherms of the lipid monolayer at the air/water interface. We found that the extrapolated area and excess free energy of the mixed monolayer deviated negatively when compared with the ideal values from additivity. Moreover, differential scanning calorimetry of the lipid mixture in aqueous dispersion showed that the gel-to-liquid crystal transition temperature increased compared with that of each pure lipid composition. These results clearly indicate that DPSB preferably interacts with DPPC in the mixture. We believe that the attraction between the oppositely charged headgroups of these lipids reinforces the intermolecular interaction. Our results provide insight into the intermolecular interaction between phospholipids and reversed-head lipids, which may prove useful for the design of lipid-based materials in the future.

Monitoring of bacterial contamination of dental unit water lines using adenosine triphosphate bioluminescence

Bacterial contamination of dental unit waterlines (DUWLs) was evaluated using ATP bioluminescence analysis and a conventional culture method. Water samples (N=44) from DUWLs were investigated for heterotrophic bacteria by culture on R2A agar, which gave counts ranging from 1.4×10³ to 2.7×10⁵ cfu/mL. The ATP bioluminescence results for DUWL samples ranged from 6 to 1189 relative light units and could be obtained within 1min; these correlated well with the culture results (r=0.727-0.855). We conclude that the results of the ATP bioluminescence assay accurately reflect the results of conventional culture-based testing. This method is potentially useful for rapid and simple monitoring of DUWL bacterial contamination.