Investigation of the appropriate viscosity of fibrinogen in repairing pleural defects using ventilation and anchoring in an ex vivo pig model.

OBJECTIVE: Our previous study revealed that the viscosity of fibrinogen could influence the effectiveness of ventilation and anchoring (V/A) methods for controlling air leakages. Here, we examined the association between the viscosity of fibrinogen and effectiveness using an ex vivo pig model. METHODS: The fibrin glue used in this study was BOLHEAL® (KM Biologics Co., Ltd., Kumamoto, Japan). We prepared three types of fibrinogen with different viscosities (higher and lower than normal), including one without additives. Using an ex vivo pig model, a pleural defect was made, and the defect was repaired using three different viscosities of fibrinogen through the V/A method. We measured the rupture pressure at the repair site (N = 10) and histologically evaluated the depth of fibrin infiltration into the lung parenchyma at the repair sites. RESULTS: The median rupture pressure was 51.5 (40-73) cmH2O in Group 1 (lower viscosity), 47.0 (47-88) cmH2O in Group 2 (no change in viscosity), and 35.5 (25-61) cmH2O in Group 3 (higher viscosity). There was no statistically significant difference between Groups 1 and 2 (p = 0.819), but the rupture pressure was significantly higher in Group 2 than in Group 3 (p = 0.0136). Histological evaluation revealed deep infiltration of fibrin into the lung parenchyma in Groups 1 and 2, but no such infiltration was observed in the higher-viscosity group. CONCLUSIONS: The results of this experiment suggested that the V/A method using fibrin glue containing low-viscosity fibrinogen was more effective in controlling air leakage due to pleural defects.

Impact of Operation on Disease Progression and Survival of Patients With Pleural Mesothelioma.

BACKGROUND: The effects of surgery on the survival of patients with pleural mesothelioma remain poorly understood. We compared the therapeutic outcomes of patients receiving neoadjuvant chemotherapy, followed by surgery or refusing surgery, for pleural mesothelioma. METHODS: This retrospective study included consecutive patients who were eligible for curative-intent surgery after 3 cycles of neoadjuvant chemotherapy with platinum plus pemetrexed at our hospital during January 2011 to December 2021. Patients were divided into 2 groups. The surgery group comprised patients who underwent curative-intent surgery for pleural mesothelioma. The refusal-of-surgery group comprised patients who were medically eligible for surgery but refused to consent to surgery. Overall survival and progression-free survival were calculated using the Kaplan-Meier method with the generalized Wilcoxon test. RESULTS: Of the 296 eligible patients for the study, 272 underwent surgery and 24 refused surgery. During the surgery, 204 patients (75.0%), 43 (15.8%), and 25 (9.2%) underwent pleurectomy/decortication, extrapleural pneumonectomy, and exploratory thoracotomy, respectively. The median follow-up length was 28.4 months. The median overall survival periods were 40.7 months (95% CI, 32.2-45.6 months) for surgery and 23.6 months (95% CI, 15.2-43.0 months) for refusal of surgery (P = .03). The median progression-free survival periods were 20.2 months (95% CI, 17.0-22.5 months) for surgery and 12.9 months (95% CI, 8.3-16.8 months) for refusal of surgery (P < .001). CONCLUSIONS: Overall survival and progression-free survival were significantly better in surgery than in refusal of surgery. Surgery may improve the survival outcomes of patients with pleural mesothelioma.

The International Association for the Study of Lung Cancer Pleural Mesothelioma Staging Project: Expanded Database to Inform Revisions in the Ninth Edition of the TNM Classification of Pleural Mesothelioma.

The International Association for the Study of Lung Cancer collaborated with the International Mesothelioma Interest Group to propose the first TNM stage classification system for diffuse pleural mesothelioma in 1995, accepted by the Union for International Cancer Control and the American Joint Committee on Cancer for the sixth and seventh edition stage classification manuals. The International Association for the Study of Lung Cancer Staging and Prognostic Factors Committee Mesothelioma Domain developed and analyzed an international registry of patients with pleural mesothelioma and updated TNM descriptors for the eighth edition of the stage classification system. To inform revisions for the forthcoming ninth edition of the TNM stage classification system, data submission was solicited for patients diagnosed between 2013 and 2022 with expanded data elements on the basis of the first project's exploratory analyses, including pleural thickness measurements, updated surgical nomenclature, and molecular markers. The resulting database consisted of a total of 3598 analyzable cases from Europe, Australia, Asia, North America, and South America, with a median age of 71 years (range: 18-99 y), 2775 (77.1%) of whom were men. With only 1310 patients (36.4%) undergoing curative-intent operations, this iteration of the database includes far more patients treated nonsurgically compared with prior. Four separate manuscripts on T, N, M, and stage groupings submitted to this journal will summarize analyses of these data and will serve collectively as the primary source of the proposed changes to the upcoming ninth edition of the pleural mesothelioma stage classification system.

Nationwide prospective registry database of patients with newly diagnosed untreated pleural mesothelioma in Japan.

Due to the scarcity of large-sized prospective databases, the Japanese Joint Committee for Lung Cancer Registry conducted a nationwide prospective registry for newly diagnosed and untreated pleural mesothelioma. All new cases diagnosed pathologically as any subtype of pleural mesothelioma in Japan during the period between April 1, 2017, to March 31, 2019, were included before treatment. Data on survival were collected in April 2021. The eligible 346 patients (285 men [82.3%]; 61 women [17.7%]; median age, 71.0 years [range, 44-88]) were included for analysis. Among these patients, 138 (39.9%) underwent surgery, 164 (47.4%) underwent non-surgical therapy, and the remaining 44 (12.7%) underwent best supportive care. The median overall survival for all 346 patients was 19.0 months. Survival rates at 1, 2, and 3 years for all patients were, 62.8%, 42.3%, and 26.5%, respectively. Median overall survival was significantly different among patients undergoing surgery, non-surgical treatment, and best supportive care (32.2 months vs. 14.0 months vs. 3.8 months, p < 0.001). The median overall survival of patients undergoing pleurectomy/decortication and extrapleural pneumonectomy was 41.8 months and 25.0 months, respectively. Macroscopic complete resection resulted in longer overall survival than R2 resection and partial pleurectomy/exploratory thoracotomy (41.8 months vs. 32.2 months vs. 16.8 months, p < 0.001). Tumor shape, maximum tumor thickness, and sum of three level thickness were significant prognostic factors. The data in the prospective database would serve as a valuable reference for clinical practice and further studies for pleural mesothelioma.

Prognosis prediction of patients with malignant pleural mesothelioma using conditional variational autoencoder on 3D PET images and clinical data.

BACKGROUND: Deep learning (DL) has been widely used for diagnosis and prognosis prediction of numerous frequently occurring diseases. Generally, DL models require large datasets to perform accurate and reliable prognosis prediction and avoid overlearning. However, prognosis prediction of rare diseases is still limited owing to the small number of cases, resulting in small datasets. PURPOSE: This paper proposes a multimodal DL method to predict the prognosis of patients with malignant pleural mesothelioma (MPM) with a small number of 3D positron emission tomography-computed tomography (PET/CT) images and clinical data. METHODS: A 3D convolutional conditional variational autoencoder (3D-CCVAE), which adds a 3D-convolutional layer and conditional VAE to process 3D images, was used for dimensionality reduction of PET images. We developed a two-step model that performs dimensionality reduction using the 3D-CCVAE, which is resistant to overlearning. In the first step, clinical data were input to condition the model and perform dimensionality reduction of PET images, resulting in more efficient dimension reduction. In the second step, a subset of the dimensionally reduced features and clinical data were combined to predict 1-year survival of patients using the random forest classifier. To demonstrate the usefulness of the 3D-CCVAE, we created a model without the conditional mechanism (3D-CVAE), one without the variational mechanism (3D-CCAE), and one without an autoencoder (without AE), and compared their prediction results. We used PET images and clinical data of 520 patients with histologically proven MPM. The data were randomly split in a 2:1 ratio (train : test) and three-fold cross-validation was performed. The models were trained on the training set and evaluated based on the test set results. The area under the receiver operating characteristic curve (AUC) for all models was calculated using their 1-year survival predictions, and the results were compared. RESULTS: We obtained AUC values of 0.76 (95% confidence interval [CI], 0.72-0.80) for the 3D-CCVAE model, 0.72 (95% CI, 0.68-0.77) for the 3D-CVAE model, 0.70 (95% CI, 0.66-0.75) for the 3D-CCAE model, and 0.69 (95% CI 0.65-0.74) for the without AE model. The 3D-CCVAE model performed better than the other models (3D-CVAE, p = 0.039; 3D-CCAE, p = 0.0032; and without AE, p = 0.0011). CONCLUSIONS: This study demonstrates the usefulness of the 3D-CCVAE in multimodal DL models learned using a small number of datasets. Additionally, it shows that dimensionality reduction via AE can be used to learn a DL model without increasing the overlearning risk. Moreover, the VAE mechanism can overcome the uncertainty of the model parameters that commonly occurs for small datasets, thereby eliminating the risk of overlearning. Additionally, more efficient dimensionality reduction of PET images can be performed by providing clinical data as conditions and ignoring clinical data-related features.

Optimal surgery for resectable malignant pleural mesothelioma in the setting of multimodality treatment.

The surgical treatment of malignant pleural mesothelioma (MPM) involves procedures to achieve macroscopic complete resection, depending on the patient's condition. We reviewed the evolution of surgical approaches for resectable MPM. Since surgery is no more than a single step in the set of processes in multimodality treatment (MMT), we concluded that these procedures should give precedence to lung preservation and minimize resection whenever possible. Postoperative quality of life must be prioritized when the patient can receive appropriate adjuvant therapy.

Efficacy and safety of nivolumab with ipilimumab for recurrent malignant pleural mesothelioma after primary surgical intervention.

BACKGROUND: Treatment of recurrent malignant pleural mesothelioma (MPM) remains challenging. Our study examined the efficacy, tolerability, and safety of nivolumab with ipilimumab treatment for recurrent MPM after primary curative-intent surgery. METHODS: Treatment comprised 360 mg nivolumab every 3 weeks and 1 mg/kg of ipilimumab every 6 weeks, both administered intravenously. Both were discontinued for progressive disease or serious adverse events (AEs). Additional post-treatment data were evaluated, including objective response rate (ORR), disease control rate (DCR), post-treatment survival, progression-free survival (PFS), and AEs. Tumor response was assessed using the modified Response Evaluation Criteria in Solid Tumors (RECIST 1.1). Survival analysis was estimated using a Kaplan-Meier plot. Feasibility analysis was performed using the National Cancer Institute Common Terminology Criteria for AEs version 5.0. RESULTS: Forty-one patients received nivolumab with ipilimumab for recurrent MPM after primary curative-intent surgery (median follow-up, 10.4 months; median treatment, 5.1 months). Overall, 18 patients exhibited partial response, 13 exhibited stable disease, and 10 had documented progressive disease. ORR and DCR were 43.9 and 75.6%, respectively. The 12-month post-treatment survival rate and PFS rate were 74.2 and 40.0%, respectively (median survival, not calculated; median PFS, 7.3 months). Further, 47 AEs were reported in 29 patients (70.7%), including grade 3-4 AEs in 14 patients (34.1%). Grade 4 hepatobiliary disorders were observed in 2 patients and grade 4 neutropenia was observed in 1. CONCLUSION: Nivolumab with ipilimumab treatment in patients with recurrent MPM after primary surgical treatment may be clinically efficacious, although serious AEs may be frequently observed.

Long-term outcomes and risk factors of residual thoracic spaces after pleurectomy/decortication for mesothelioma.

OBJECTIVES: The residual thoracic spaces (RTS) after pleurectomy/decortication (P/D) remain unexplored to date. Hence, this study aims to examine the details and risk factors of RTS during the 3 post-P/D months. METHODS: We retrospectively examined patients who underwent neoadjuvant chemotherapy, followed by P/D for malignant pleural mesothelioma from September 2012 to December 2020. The RTS group included cases of residual thoracic cavity unaccompanied by pleural effusion on 3 postoperative months computed tomography. We determined risk factors for RTS using univariable and multivariable analyses. RESULTS: Of 170 patients examined, 58 (34.1%) were in the RTS group and 112 (65.9%) in the non-RTS group. In the RTS group, 43 patients recovered from RTS during the follow-up period; 4 patients developed chronic fistular empyema, while 2 required fenestration and 2 were thoracoscopic debridement. Besides, 11 patients exhibited RTS continuously. The univariable analysis revealed that compared with the non-RTS group, the RTS group reported a significantly longer postoperative air leak (>7 days; P < 0.01) and right P/D (P = 0.04). The multivariable analysis demonstrated that longer postoperative air leak (>7 days) remained a risk factor for RTS (odds ratio 2.5, 95% confidence interval: 1.3-4.9, P < 0.01). CONCLUSIONS: RTS was a postoperative event that frequently observed in patients undergoing P/D. Overall, the current study findings suggest longer postoperative air leak (>7 days) as a significant risk factor for RTS.

Incidence and Risk Factors of Chest Wall Metastasis at Biopsy Sites in Patients with Malignant Pleural Mesothelioma.

To investigate the incidence and risk factors of chest wall metastasis (CWM) at biopsy sites in patients with malignant pleural mesothelioma (MPM). This retrospective cohort study was conducted in 262 consecutive MPM patients who underwent multimodal treatment in which including neoadjuvant chemotherapy (NAC) and curative-intent surgery, from August 2009 to March 2021. CWM was evaluated radiologically (r-CWM) and pathologically (p-CWM). We also investigated the risk factors of p-CWM and the consistency between r-CWM and p-CWM. Of 262 patients, 25 patients were excluded from analysis due to missing data or impossibility of evaluation. Of the eligible 237 patients, pleural biopsy was performed via video-assisted thoracoscopic surgery in 197 (83.1%) and medical thoracoscopy in 40 (16.9%). Pleurodesis was performed after pleural biopsy in 74 patients (31.2%). All patients received NAC followed by curative-intent surgery. Radiological examination showed r-CWM in 43 patients (18.1%), while pathological examination showed p-CWM in 135 patients (57.0%). The incidence of p-CWM was significantly higher in the patients who received pleurodesis after pleural biopsy (77.0% vs. 47.9%, <0.001). Multivariate logistic regression analysis for p-CWM revealed that pleurodesis is an independent risk factor of p-CWM (adjusted hazard ratio, 3.46; 95% confidence interval, 1.84−6.52, <0.001). CWM at the biopsy site was pathologically proven in more than half of the patients (57.0%) who received NAC followed by curative-intent surgery, which was higher than the numbers diagnosed by radiological examinations (p-CWM: 57.0% vs. r-CWM: 18.1%). Pleurodesis after pleural biopsy is an independent risk factor of p-CWM.

Association between thoracic epidural block and major complications after pleurectomy/decortication for malignant pleural mesothelioma under general anesthesia.

INTRODUCTION: A curative-intent surgical procedure, pleurectomy/decortication, for malignant pleural mesothelioma is accompanied by a high incidence of major postoperative complications. Although epidural block, which suppresses nociception during and after surgery, reportedly has both benefits and disadvantages in terms of outcomes after thoracic surgery for other diseases, the effects of epidural block on major complications after pleurectomy/decortication have not been evaluated. The aim of this study was to evaluate the association between epidural block and major postoperative complications following pleurectomy/decortication. METHODS: In a single-institutional observational study, consecutive adult patients undergoing pleurectomy/decortication under general anesthesia were enrolled from March 2019 to December 2021. Multivariable logistic regression analysis was performed to determine the association between perioperative variables and major complications. Next, patients were divided into two groups: general anesthesia with and without epidural block. Incidences of major postoperative complications, defined as Clavien-Dindo grades≥III, were compared between groups. RESULTS: In all patients enrolled with American Society of Anesthesiologists (ASA) physical status II or III (n=99), general anesthesia without epidural block was identified as a sole risk factor for major complications among perioperative variables. The incidence of major complications was 32.3% (95% CI 19.1% to 49.2%) in patients with epidural block (n=34), which was significantly lower than 63.1% (95% CI 50.9% to 73.8%) in patients without epidural block (n=65). In sensitivity analysis in patients with ASA physical status II alone, the same results were obtained. CONCLUSION: Epidural block is likely associated with reduction of the incidence of major complications after pleurectomy/decortication for malignant pleural mesothelioma under general anesthesia.

Control of air leakage during pleurectomy/decortication by the ventilation and anchoring method.

OBJECTIVES: We previously established a novel method of lung repair called the ventilation and anchoring (V/A) method. We evaluated the usefulness of the V/A method for controlling air leakage during pleurectomy/decortication (P/D). METHODS: For this study, we enrolled patients with malignant pleural mesothelioma (MPM) who planned to receive P/D. Our lung repair method involves (1) suturing lung parenchyma for an apparent injured lesion and (2) coating the lung parenchyma with fibrin glue (FG) using the V/A method. The tidal volume (TV) was measured under pressure-controlled ventilation in the ipsilateral-affected lung 10 times at the following four points: after thoracotomy, at completion of visceral pleurectomy, after suturing lung parenchyma, and 5 min after coating with FG. The primary endpoint was the mean TV (mTV) change, and the secondary endpoints were the duration of air leakage and incidence of pleurodesis. RESULTS: Between April 2014 and April 2016, 25 patients of the 29 consecutive patients enrolled were eligible. The mTV significantly decreased after completion of visceral pleurectomy but significantly increased after repair of the lung parenchyma, especially after coating with FG. The median duration of postoperative air leakage was 4 days (range: 2-19 days). Postoperative air leakage > 7 days was observed in 11 (44%) patients. Of these 11 patients, 6 received pleurodesis; however, no further revision was needed. CONCLUSIONS: Significant increases in TV were observed after coating with FG via the V/A method during P/D. Coating with FG using the V/A method can contribute to a reduction in air leakage during P/D.

Neoadjuvant pemetrexed plus cisplatin followed by pleurectomy for malignant pleural mesothelioma.

PURPOSE: Despite becoming the preferred surgical technique for malignant pleural mesothelioma, pleurectomy/decortication has received few prospective clinical trials. Therefore, the Japan Mesothelioma Interest Group conducted a prospective multi-institutional study to evaluate the feasibility of neoadjuvant chemotherapy followed by pleurectomy/decortication. METHODS: Patients with histologically confirmed, resectable malignant pleural mesothelioma underwent neoadjuvant chemotherapy comprising pemetrexed 500 mg/m2 plus cisplatin 75 mg/m2 for 3 cycles, followed by pleurectomy/decortication. The primary end point was macroscopic complete resection rate regardless of the surgical technique used. RESULTS: Among the 24 patients enrolled, 20 received neoadjuvant chemotherapy and 18 proceeded to surgery, all of whom achieved macroscopic complete resection. Pleurectomy/decortication was performed in 15 patients. The trial satisfied the primary end point, with a macroscopic complete resection rate of 90% (18/20, 95% confidence interval, 68.3-98.8). No treatment-related 30- and 90-day mortality occurred. The overall survival after 1 and 2 years and median overall survival after registration were 95.0% (95% confidence interval, 69.5-99.3), 70.0% (95% confidence interval, 45.1-85.3), and 3.45 years (95% confidence interval, 1.64 to not available), respectively. The cumulative incidence of progression after 1 and 2 years and median time to progression were 33.3% (95% confidence interval, 17.3-64.1), 61.1% (95% confidence interval, 42.3-88.3), and 1.71 years (95% confidence interval, 1.00-2.99), respectively. The best postoperative value for forced expiratory volume was 78.0% of preoperative values. CONCLUSIONS: Neoadjuvant chemotherapy followed by pleurectomy/decortication was feasible with acceptable survival and mortality/morbidity. Postoperative pulmonary function was approximately 80% of the preoperative pulmonary function.

Japanese Current Status of Curative-Intent Surgery for Malignant Pleural Mesothelioma.

BACKGROUND: Few reports about surgical outcomes in malignant pleural mesothelioma (MPM) have been based on reliable nationwide databases. Here, we analyzed the incidence, surgical outcome, and operative risk factors using Japanese nationwide database. METHODS: Characteristics and perioperative data from 622 patients who underwent curative-intent surgery for MPM between January 2014 and December 2017 were recorded from National Clinical Database of Japan. We analyzed the incidence, surgical outcomes, and risk factors for surgical complications after 2 surgical procedures (extrapleural pneumonectomy [EPP] and pleurectomy/decortication [P/D]). RESULTS: During 4 years, EPP was performed in 279 patients and P/D in 343. EPP was more frequently performed in institutions less experienced in MPM, while P/D was more frequently performed in institutions well experienced in MPM (P < .001), especially in high-volume centers with more than 10 cases during this period. P/D was more frequently performed, especially in high-volume centers. The morbidity rates were 45.2% in EPP and 35.9% in P/D. Heart failure and pneumonia were most frequent in EPP, while prolonged air leakage was most frequent in P/D. Thirty-day and in-hospital mortality rates were 1.1% and 3.2% (EPP) and 1.2% and 3.2% (P/D), respectively. Regression analyses revealed that higher age (>65 years) was associated with operative complications in EPP (odds ratio, 3.56 [95% confidence interval, 1.26-8.56]), whereas no risk factor was observed in P/D. CONCLUSIONS: In Japanese nationwide annual database, P/D was more frequently performed, especially in high-volume centers. Morbidity was higher in EPP than P/D; however, the mortality rates were quite low in Japan regardless surgical procedures.

Non-incisional pleurectomy/decortication for malignant mesothelioma after cardiac surgery.

A 70-year-old man diagnosed with right-sided malignant epithelial pleural mesothelioma, underwent pleurectomy/decortication after three courses of neoadjuvant chemotherapy. He had a history of mitral valve replacement and maze procedure with median sternotomy, and the procedures resulted in strong adhesion from the apex to the mediastinal side. In particular, the peeling of the area where the tumor invaded the pericardium required the most attention; however, the involved pericardium could be partially resected without damaging the right atrium. Finally, en bloc macroscopic complete resection with the entire pleura was successfully performed without conversion to extrapleural pneumonectomy.

The utility of 68F-FDG PET/CT for evaluation of tumor response to immune checkpoint inhibitor therapy and prognosis prediction in patients with non-small-cell lung cancer.

OBJECTIVE: To compare three fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) (EORTC criteria and PERCIST) and computed tomography (CT) (RECIST1.1) for response evaluation and prognosis prediction in non-small-cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitor (ICI) monotherapy. SUBJECTS AND METHODS: Forty NSCLC patients underwent 18F-FDG PET/CT scans at baseline and after 4 to 8 cycles of nivolumab or pembrolizumab. Therapeutic response was evaluated according to EORTC criteria, PERCIST, and RECIST1.1,then concordance among those was assessed using Cohen's κ coefficient. Progression-free survival (PFS) and overall survival (OS) was examined using log-rank and Cox methods. RESULTS: The number of complete metabolic response (CMR)/partial metabolic response (PMR)/stable metabolic disease (SMD)/progressive metabolic disease (PMD) were 8/10/4/18 for EORTC criteria and 9/9/4/18 for PERCIST. Using RECIST1.1, those of CR/PR/SD/PD were 4/10/12/14. Although there was high concordance between PERCIST and EORTC (92.5% of patients; κ=0.924), that between PERCIST and RECIST1.1 was substantial (65.0%; κ=0.560) and that between EORTC and RECIST1.1 (65.0%; κ=0.574). After a median 23.2 months (range 7.2 to 51.8 months), 32 patients had documented progression and 24 patients died from NSCLC. According to both PET and CT, patients with no progression (CMR/PMR/SMD or CR/PR/SD) showed significantly longer PFS and OS than PMD or PD patients (EORTC: P<0.0001 and P<0.0001, respectively, PERCIST: P<0.0001 and P=0.0001, respectively, RECIST1.1: P<0.0001 and P<0.0001, respectively). In a univariate analysis total MTV (P=0.042) on pre-ICI treatment 18F-FDGPET/CT scans was significantly associated with progression. Highest SUVmax (P<0.0001), total MTV (P=0.0062), total TLG (P<0.0001), highest SULpeak (P<0.0001), and total TLGL (P<0.0001) on post-ICI treatment 18F-FDG PET/CT scans were also were significantly associated with progression. Moreover, the change rate of highest SUVmax (P<0.0001), total metabolic tumor volume (MTV) (P<0.0001), total lesion glycolysis(TLG) (P<0.0001), highest SULpeak (P<0.0001), total TLGL (P<0.0001), size (P=0.0012), EORTC (P<0.0001), PERCIST (P<0.0001), and RECIST 1.1 (P<0.0001) on two PET/CT scans were significantly associated with progression. A multivariate analysis confirmed the change rate of total MTV (P=0.034), and total TLGL (P=0.0027), EORTC (P=0.018), PERCIST (P=0.045), and RECIST1.1 (P=0.0037) as independent negative PFS predictors. CONCLUSION: Both 18F-FDG PET (EORTC criteria and PERCIST) and CT (RECIST1.1) after 4 to 8ICI monotherapy cycles are accurate for evaluation of tumor response and predicting prognosis in NSCLC patients.

Radiation Pneumonitis After Volumetric Modulated Arc Therapy for Non-small Cell Lung Cancer.

BACKGROUND/AIM: To evaluate the incidence and grade of radiation pneumonitis after volumetric modulated arc therapy (VMAT) performed for the treatment of non-small cell cancer (NSCLC). PATIENTS AND METHODS: Fifty consecutive non-surgical candidates with NSCLC underwent VMAT. Thirty-five patients had stage-III tumors and 15 had recurrent tumors. The prescribed radiation dose for the gross tumor and the elective nodal area was 69 Gy in 30 fractions and 51 Gy in 30 fractions, respectively. RESULTS: Radiation pneumonitis developed in 38 patients (76%, 38/50), and grade ≥2 radiation pneumonitis developed in 11 patients (22%, 11/50). The percentage of lung volume that received a dose in excess of 5 Gy (V5), V10, V20, V30, and the mean lung dose (MLD) in the bilateral and ipsilateral lung were significantly associated with the development of grade ≥2 radiation pneumonitis. CONCLUSION: The incidence and degree of radiation pneumonitis are acceptable following treatment of NSCLC with VMAT.

Relationship Between Physical Function and Health Utility in Patients Undergoing Surgical Treatment for Malignant Pleural Mesothelioma.

PURPOSE: Health utility, which is a measure of patient-reported outcome (PRO), has recently been used in health-related quality of life for patients with various cancers. However, the relationship between health utility and the physical function and of patients undergoing pleurectomy/decortication (P/D) as surgical treatment for malignant pleural mesothelioma (MPM) has not been reported in the perioperative and convalescent phases. This study aimed to evaluate the perioperative and postoperative health utility of patients undergoing P/D for MPM at one year postoperatively and to examine the relationship with physical function. METHODS: We included patients underwent P/D. Grip strength, knee extension strength, 6-minute walk distance (6MWD), forced vital capacity (FVC), and forced expiratory volume in one second (FEV1) were measured to assess physical function, and the Short-Form Six-Dimension (SF-6D) was completed to assess health utility. These assessments were performed preoperatively, postoperatively, and one year postoperatively. Statistical analysis was performed using one-way analysis of variance for comparison of pre and postoperative and one year mean values. RESULTS: There were 24 subjects (23 males, 65.5±8.3 year). SF-6D, 6MWD, FVC, and FEV1 values one year operatively improved significantly compared with postoperative. Additionally, SF-6D was correlated with 6MWD. CONCLUSION: Health utility were also correlated with exercise capacity.

18F-FDG PET/CT for monitoring anti-PD-1 therapy in patients with non-small cell lung cancer using SUV harmonization of results obtained with various types of PET/CT scanners used at different centers.

OBJECTIVE: The prognostic value of treatment response in patients with non-small cell lung cancer (NSCLC) treated with immune-checkpoint inhibitors (ICIs) shown by 18F-fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) results obtained with multiple types of PET scanners using standardized uptake value (SUV) harmonization was evaluated. METHODS: Fifty-eight patients treated with ICIs who underwent 18F-FDG PET/CT examinations with nine types of PET scanners at six hospitals were enrolled. SUV harmonization of multiple PET scanner results was performed using the dedicated software packages "RAVAT" and "RC Tool for Harmonization". Tumor response was assessed by change in sum of harmonized SUVmax, according to the European Organization for Research and Treatment of Cancer (EORTC5) or the SUV of up to five lesions normalized to lean body mass, according to the PET Response Criteria in Solid Tumors (PERCIST5) and immunotherapy-modified PERCIST (imPERCIST5) criteria. The correlation between tumor response according to those three definitions and overall survival (OS) was evaluated and compared to known prognostic factors. RESULTS: One-year OS in responders and non-responders for harmonized EROTC5 was 86 and 32%, for harmonized PERCIST5 was 86 and 32%, and for harmonized imPERCIST5 was 80 and 30%, respectively (each p = 0.001). Univariate analysis showed that all response criteria remained as prognostic factors. However, there was an overlap for the categories stable metabolic disease (SMD) and progression metabolic disease (PMD) in survival curves using the PET treatment response criteria. CONCLUSION: In patients with NSCLC treated with ICIs, tumor response based on the harmonized response criteria was associated with OS. PET response criteria using harmonized metabolic parameters may be difficult to routinely employ in daily practice due to overlapping SMD and PMD, although may have a supporting role for determining prognosis.

Deep learning with deep convolutional neural network using FDG-PET/CT for malignant pleural mesothelioma diagnosis.

OBJECTIVES: This study analyzed an artificial intelligence (AI) deep learning method with a three-dimensional deep convolutional neural network (3D DCNN) in regard to diagnostic accuracy to differentiate malignant pleural mesothelioma (MPM) from benign pleural disease using FDG-PET/CT results. RESULTS: For protocol A, the area under the ROC curve (AUC)/sensitivity/specificity/accuracy values were 0.825/77.9% (81/104)/76.4% (55/72)/77.3% (136/176), while those for protocol B were 0.854/80.8% (84/104)/77.8% (56/72)/79.5% (140/176), for protocol C were 0.881/85.6% (89/104)/75.0% (54/72)/81.3% (143/176), and for protocol D were 0.896/88.5% (92/104)/73.6% (53/72)/82.4% (145/176). Protocol D showed significantly better diagnostic performance as compared to A, B, and C in ROC analysis (p = 0.031, p = 0.0020, p = 0.041, respectively). MATERIALS AND METHODS: Eight hundred seventy-five consecutive patients with histologically proven or suspected MPM, shown by history, physical examination findings, and chest CT results, who underwent FDG-PET/CT examinations between 2007 and 2017 were investigated in a retrospective manner. There were 525 patients (314 MPM, 211 benign pleural disease) in the deep learning training set, 174 (102 MPM, 72 benign pleural disease) in the validation set, and 176 (104 MPM, 72 benign pleural disease) in the test set. Using AI with PET/CT alone (protocol A), human visual reading (protocol B), a quantitative method that incorporated maximum standardized uptake value (SUVmax) (protocol C), and a combination of PET/CT, SUVmax, gender, and age (protocol D), obtained data were subjected to ROC curve analyses. CONCLUSIONS: Deep learning with 3D DCNN in combination with FDG-PET/CT imaging results as well as clinical features comprise a novel potential tool shows flexibility for differential diagnosis of MPM.

Quality of life and lung function after pleurectomy/decortication for malignant pleural mesothelioma.

OBJECTIVES: Impact of pleurectomy/decortication (P/D) on quality of life (QOL) is not widely reported. We investigated QOL and lung function after P/D. METHODS: A single-centre, retrospective cohort study was performed among patients who underwent P/D for malignant mesothelioma between June 2014 and June 2018 at Hyogo College of Medicine. Data at 4 points before and 3, 6 and 12 months on QOL and lung function were evaluated with the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and pulmonary function tests. RESULTS: Forty-five out of 65 patients completed SF-36. Physical function and role physical decreased from 78 to 65 and 69 to 41 and did not recover. Body pain decreased from 74 to 52. It increased to 62 at 12 months but was lower than before. General health perceptions, vitality and social function decreased from 56 to 49, 50 to 47 and 63 to 50, respectively, but returned to baseline. Role emotional decreased from 75 to 54, then once increased to 63, but decreased again to 58. Mental health tended to improve from 58 to 70. Thirty-eight patients out of 45 completed pulmonary function tests. Forced vital capacity and forced expiratory volume in 1 s decreased from 98% to 61% and 93% to 67% and did not increase. Right-sided surgery or complications was the risk factors of poor lung function but no significant risk factors in QOL. CONCLUSIONS: This study suggests that P/D had an impact on QOL. Despite the lack of recovery in lung function QOL in mental aspects tended to improve, suggesting that pulmonary function tests alone are limited in assessing QOL.