Current Status and Future Perspectives of Preoperative and Intraoperative Marking in Thoracic Surgery.

The widespread implementation of lung cancer screening and thin-slice computed tomography (CT) has led to the more frequent detection of small nodules, which are commonly referred to thoracic surgeons. Surgical resection is the final diagnostic and treatment option for such nodules; however, surgeons must perform preoperative or intraoperative markings for the identification of such nodules and their precise resection. Historically, hook-wire marking has been performed more frequently worldwide; however, lethal complications, such as air embolism, have been reported. Therefore, several surgeons have recently attempted to develop novel preoperative and intraoperative markers. For example, transbronchial markings, such as virtual-assisted lung mapping and intraoperative markings using cone-beam computed tomography, have been developed. This review explores various marking methods that have been practically applied for a better understanding of preoperative and intraoperative markings in thoracic surgery. Recently, several attempts have been made to perform intraoperative molecular imaging and dynamic virtual three-dimensional computed tomography for the localization, diagnosis, and margin assessment of small nodules. In this narrative review, the current status and future perspectives of preoperative and intraoperative markings in thoracic surgery are examined for a better understanding of these techniques.

Virtual thoracoscopic imaging for accurate pulmonary nodule localization: clinical experience.

The increasing detection of small pulmonary nodules on computed tomography (CT) warrants simple and effective nodule localization methods. We describe our clinical experience using an experimental computer that displays virtual thoracoscopic images. This device constructs three-dimensional images from preoperative CT scans and simulates the deflated lung parenchyma in the lateral decubitus position. Five patients underwent lung resection using this technology. The device provided images that closely resembled actual thoracoscopic images in all cases. This method addresses the limitations of other localization techniques such as allergic reactions and mechanical marker-related complications. The method only requires preoperative CT images, and the process is semi-automatically performed by specifying the nodule location, thoracoscopic camera insertion site, and camera angle. This study is still in the preliminary phase and has several limitations. However, this method has the potential to accurately predict nodule locations and eliminate the many risks associated with other techniques.

Blood eosinophil count correlates with alveolar damage in emphysema-predominant COPD.

BACKGROUND: Although blood eosinophil count is recognized as a useful biomarker for the management of chronic obstructive pulmonary disease (COPD), the impact of eosinophils in COPD has not been fully elucidated. Here we aimed to investigate the relationships between the blood eosinophil count and various clinical parameters including lung structural changes. METHODS: Ninety-three COPD patients without concomitant asthma were prospectively enrolled in this study. Blood eosinophil count, serum IgE level, serum periostin level, and chest computed tomography (CT) scans were evaluated. Eosinophilic COPD was defined as COPD with a blood eosinophil count ≧ 300/µL. We examined the correlation between the blood eosinophil count and structural changes graded by chest CT, focusing specifically on thin airway wall (WT thin) and thick airway wall (WT thick) groups. In a separate cohort, the number of eosinophils in the peripheral lungs of COPD patients with low attenuation area (LAA) on chest CT was assessed using lung resection specimens. RESULTS: The mean blood eosinophil count was 212.1/µL, and 18 patients (19.3%) were categorized as having eosinophilic COPD. In the whole group analysis, the blood eosinophil count correlated only with blood white blood cells, blood basophils, C-reactive protein level, and sputum eosinophils. However, the blood eosinophil count positively correlated with the percentage of LAA and negatively correlated with the diffusing capacity for carbon monoxide in the WT thin group. Lung specimen data showed an increased number of eosinophils in the peripheral lungs of COPD patients with LAA on chest CT scans compared to normal controls. CONCLUSIONS: Some COPD patients without concomitant asthma showed a phenotype of high blood eosinophils. Alveolar damage may be related to eosinophilic inflammation in patients with COPD without asthma and thickening of the central airway wall.

Impact of the expanded indication of robot-assisted thoracic surgery for mediastinal tumors.

OBJECTIVE: Following the introduction of robot-assisted thoracoscopic surgery (RATS) as a health insurance-covered treatment in Japan, we investigated the current status and impact of the expansion of the indications for RATS for mediastinal tumors. METHODS: Between 2018 and 2022, 209 cases of total mediastinal tumor resection were performed in our hospital. The study period was divided into the first half (January 2018 to June 2020) and the second half (July 2020 to December 2022), and perioperative parameters were compared between the two groups. RESULTS: Ninety-six surgical procedures were performed in the first half and 113 in the second half. The percentage of RATS approach was significantly higher in the second half compared with the first half (P < 0.001). Indications for RATS in the second half compared with the first half were significantly increased in patients with stage II (P < 0.001) and stage III (P = 0.026) thymomas, tumor diameter ≥ 50 mm (P < 0.011), and patients undergoing extended thymectomy for myasthenia gravis (P < 0.009). In respect of short-term postoperative parameters, the estimated intraoperative blood loss (P < 0.035), postoperative drain duration (P < 0.037), and postoperative hospital stay (P < 0.011) were significantly lower in the second half than in the first half. CONCLUSIONS: RATS has recently been expanded for mediastinal tumors with improved short-term outcomes in our hospital after health insurance was applied in Japan. In the future, it will be necessary to discuss the further expansion of its indications by taking into account safety and long-term outcomes.

Incidence of air leaks in patients undergoing robotic thoracic surgery and video-assisted thoracic surgery.

Postoperative air leakage is the most common complication in surgery for malignant lung tumors, leading to extended hospital stays and substantial medical expenses. This study aimed to identify the incidence and characteristics of intraoperative and postoperative air leaks in both robotic-assisted thoracic surgery (RATS) and video-assisted thoracic surgery (VATS), as well as the causes of persistent air leakage following RATS. We conducted a retrospective analysis of patients who underwent lung resection for malignant lung tumors at our institution from October 2018 to August 2022. We compared the incidence rates of intraoperative air leak, postoperative air leak, and persistent air leak between patients who underwent RATS and those who underwent VATS. Background factors were adjusted using propensity score matching. A subanalysis was performed to compare unexpected air leaks, defined as air leaks not observed intraoperatively but confirmed postoperatively. The study included 295 cases of RATS and 227 cases of VATS. In both the overall population and the matched group (187 cases each for RATS and VATS), RATS demonstrated a significantly higher incidence of persistent air leaks compared to VATS (11% vs 3%, p < 0.01; 9% vs 3%, p = 0.02, respectively). RATS also had a significantly higher incidence of unexpected air leaks compared with VATS (29% vs 18%, p = 0.05). Although there was no statistically significant difference in hospital stays, RATS showed a higher incidence of postoperative persistent air leaks and unexpected postoperative air leaks than VATS.

Transcriptomic profiling of a late recurrent nuclear protein in testis carcinoma of the lung 14 years after the initial operation: a case report.

Background: Nuclear protein in testis (NUT) carcinoma (NC) of the lung is a rare cancer that occurs mainly in young adolescents and adults. NC is genetically characterized by NUTM1 rearrangements, which usually take the form of BRD4-NUT fusions. The prognosis for NC is dismal, and treatment with conventional chemotherapeutic regimens is ineffective. Case Description: We herein describe the case of a 53-year-old woman with recurrent NC of the lung 14 years after surgery for nasal cavity cancer. Chest computed tomography revealed a 5.5-cm tumor in the lower lobe of the left lung. We completely resected the recurrent lung NC via thoracotomy. Immunohistochemistry (IHC) of the lung and nasal cavity cancers showed diffuse strong expression of NUT. RNA-seq of the lung NC revealed NUTM1 rearrangement, with a fusion of BRD4 exon 10 to NUTM1 exon 4. This breakpoint has never been reported before. In addition, IHC revealed elevated expression of parathyroid hormone-like hormone in the lung NC but not in the nasal cavity NC, indicating that the lung and nasal cavity NCs were metachronous multiple primary cancers. Conclusions: We experienced a rare recurrence of lung NC 14 years after the initial surgery. The BRD4-NUT fusion consisted of a new breakpoint. Furthermore, the expression pattern of parathyroid hormone-like hormone (PTHLH) suggested that the NCs in the nasal cavity and lung may be metachronous multiple lung cancers. This extremely rare case highlighted the possibility of identifying less malignant NCs in patients with poorly differentiated tumors via fusion gene analysis and the need to develop more effective treatment strategies for this malignancy.

2D/3D deformable registration for endoscopic camera images using self-supervised offline learning of intraoperative pneumothorax deformation.

Shape registration of patient-specific organ shapes to endoscopic camera images is expected to be a key to realizing image-guided surgery, and a variety of applications of machine learning methods have been considered. Because the number of training data available from clinical cases is limited, the use of synthetic images generated from a statistical deformation model has been attempted; however, the influence on estimation caused by the difference between synthetic images and real scenes is a problem. In this study, we propose a self-supervised offline learning framework for model-based registration using image features commonly obtained from synthetic images and real camera images. Because of the limited number of endoscopic images available for training, we use a synthetic image generated from the nonlinear deformation model that represents possible intraoperative pneumothorax deformations. In order to solve the difficulty in estimating deformed shapes and viewpoints from the common image features obtained from synthetic and real images, we attempted to improve the registration error by adding the shading and distance information that can be obtained as prior knowledge in the synthetic image. Shape registration with real camera images is performed by learning the task of predicting the differential model parameters between two synthetic images. The developed framework achieved registration accuracy with a mean absolute error of less than 10 mm and a mean distance of less than 5 mm in a thoracoscopic pulmonary cancer resection, confirming improved prediction accuracy compared with conventional methods.

Multidisciplinary treatment of giant thymoma, paving the way to complete surgical resection: a case report.

BACKGROUND: A multidisciplinary treatment approach is recommended for patients with extensive, advanced, or recurrent thymomas. However, detailed treatment strategies, such as chemotherapy regimens and optimal surgical procedures, are still under debate. CASE PRESENTATION: We report a case of gigantic locally advanced thymoma. A 70-year-old male was referred to our hospital following the detection of abnormal chest shadows. Chest X-ray and computed tomography (CT) scans revealed a 21-cm mass in the anterior mediastinum, encircling the pulmonary hilum and extending into the left thoracic cavity. PET/CT showed increased 18F-fluorodeoxyglucose uptake at the tumor site. Based on a trans-percutaneous CT-guided needle biopsy, the tumor was diagnosed as a Type B2 thymoma at the clinical IIIA stage. The patient underwent four cycles of preoperative induction chemotherapy, including cisplatin, doxorubicin, and methylprednisolone (CAMP), resulting in a partial response; the tumor shrank to 12 cm and FDG uptake decreased. Considering the patient's age and comorbidities, we performed total thymectomy, along with partial resections of the parietal, mediastinal and visceral pleura, pericardium, and left upper lobectomy. This approach achieved complete histological resection, mitigating the risk of recurrence. Pathological analysis confirmed a thymoma, ypT3 (lung) N0M0 stage IIIA, with no malignancy in the pericardial or pleural effusions. No recurrence was detected 9 months post-surgery. CONCLUSIONS: We report a case of giant thymoma successfully treated with multidisciplinary strategy. Surgical treatment alone may not have achieved complete resection, but after inducing significant tumor shrinkage with preoperative CAMP therapy, we were able to achieve complete resection. This treatment strategy may be effective in large thymoma cases.

Efficacy of Immune Checkpoint Inhibitors in Postoperative Recurrence of Wild-type EGFR Non-Small Cell Lung Cancer.

BACKGROUND/AIM: Immune checkpoint inhibitors (ICIs) have been widely used in the treatment of non-small cell lung cancer (NSCLC), but specific outcomes of ICIs treatment among patients with postoperative recurrence of NSCLC remain unclear. The objective of the study was to compare the efficacy of ICIs and chemotherapy with conventional chemotherapy only in patients with postoperative recurrence of epidermal growth factor receptor (EGFR) wild-type NSCLC. PATIENTS AND METHODS: A retrospective analysis was performed on patients who underwent anatomical lung resection at the Nagoya University Hospital and were treated for postoperative recurrence of wild-type EGFR NSCLC. This study evaluated the prognosis for postoperative recurrence, including ICIs treatment and other clinicopathological factors. RESULTS: Of the 83 patients included in the analysis, 20 patients underwent chemotherapy and 63 patients underwent chemotherapy combined with ICIs. The combination of ICIs and chemotherapy significantly prolonged survival after recurrence (median survival: 33.1 months vs. 22.0 months, p=0.01). In the ICIs group, no significant differences in survival were detected between patients with different programmed death ligand 1 (PD-L1) status (Tumor Proportion Scores: <1%, 1%-49%, ≥50%, p=0.27). Multivariate analysis revealed that postoperative distant recurrence was a significant poor prognostic factor for survival after recurrence (HR=1.85, 95% CI=1.06-3.25, p=0.03), and combining ICIs with chemotherapy significantly improved survival after recurrence (HR=0.43, 95% CI=0.24-0.78, p<0.01). CONCLUSION: Combination of ICIs with chemotherapy significantly prolonged survival of postoperative recurrence with wild-type EGFR NSCLC regardless of PD-L1 status.

Endobronchial Closure for Peripheral Pulmonary Air Leakage.

INTRODUCTION: A minimally invasive alternative to surgery for treating pneumothorax has been developed, aiming to reduce risks while maintaining efficacy. This study conducted basic experiments using ex vivo and in vivo pig lung employing a super-thin catheter for treatment. This new device injects fibrin glue directly into the responsible lesion to close the air leak, which has two features: thin design and double-lumen. METHODS: The experimental setup involved utilizing trachea and both lung specimens from pigs under positive pressure ventilation. To simulate pneumothorax, artificial fistulas were created on the lung surfaces. The super-thin catheter, guided through a bronchoscope near the fistula, was used to embolize the peripheral bronchus by injecting a fibrin preparation. Then, an air leak test was conducted afterward to assess the efficacy of the treatment. Additionally, a similar pneumothorax model was induced in alive pig under general anesthesia to evaluate its curability. RESULTS: In the extracted pig lungs, embolization was performed in 21 cases, resulting in the cessation of air leaks in 19 cases, corresponding to a 90.5% cure rate. Notably, no major adverse events occurred with the treatment devices. Similarly, in living pigs, pneumothorax was successfully treated, with no recurrence observed up to the seventh postoperative day. CONCLUSION: The novel treatment device utilizing a super-thin catheter offers a minimally invasive and highly curative option for pneumothorax. These promising results suggest the potential for further development and human clinical trials, which could revolutionize the treatment of pneumothorax, reducing risks and improving outcomes.

Future directions for xenotransplantation in lungs.

PURPOSE OF REVIEW: Advancements in preclinical xenotransplant studies have opened doors for clinical heart and kidney xenotransplantation. This review assesses recent progress in lung xenotransplantation research and its potential clinical implications. RECENT FINDINGS: The efficacy of the humanized von Willebrand factor in reducing platelet sequestration in ex-vivo and in-vivo lung xenotransplant models was showcased. Combining human tissue factor pathway inhibitor and CD47 expression with selectin and integrin inhibition delayed neutrophil and platelet sequestration. Enhanced expression of human complement regulatory proteins and thrombomodulin in genetically engineered pig lungs improved graft survival by reducing platelet activation and modulating coagulation disruptions. Knocking out the CMAH gene decreased antibody-mediated inflammation and coagulation activation, enhancing compatibility for human transplantation. Furthermore, CMAH gene knockout in pigs attenuated sialoadhesin-dependent binding of human erythrocytes to porcine macrophages, mitigating erythrocyte sequestration and anemia. Meanwhile, in-vivo experiments demonstrated extended survival of xenografts for up to 31 days with multiple genetic modifications and comprehensive treatment strategies. SUMMARY: Experiments have uncovered vital insights for successful xenotransplantation, driving further research into immunosuppressive therapy and genetically modified pigs. This will ultimately pave the way for clinical trials designed to improve outcomes for patients with end-stage lung disease.

Updated outcomes of surgical treatment for recurrent thymic tumour: a report from the Japanese nationwide database.

OBJECTIVES: This study aimed to analyse the surgical outcomes for recurrent thymic epithelial tumours and identify the factors associated with post-recurrence survival, using an updated Japanese nationwide database. METHODS: The cohort that developed recurrence after the initial resection was extracted from an updated database of patients whose thymic epithelial tumours were treated surgically between 1991 and 2010. Furthermore, we reviewed clinicopathological and prognostic factors of re-resected cases. Post-recurrence survival outcomes and cause-specific deaths in non-re-resected cases were also reviewed. RESULTS: We enrolled 191 patients who underwent re-resection and 259 patients who did not. In the surgery group, more patients with early stage disease, less aggressive World Health Organization (WHO) histological classification, initial complete resection and shorter recurrence-free intervals were included. Non-thymic carcinoma, absence of preoperative treatment, longer recurrent-free interval, single-site recurrence and R0-1 re-resection were all significantly favourable prognostic factors for post-recurrence survival in the surgery group, according to univariable analyses. Non-thymic carcinoma histology, longer recurrence-free interval and R0-1 re-resection were identified as independent prognostic factors according to multivariable analysis. The post-recurrence survival of the entire cohort with R2 re-resection was significantly better than that of the non-surgery group, although it was not demonstrated that patients with thymoma who underwent R2 re-resection had significantly better post-recurrence and lower cause-specific death. CONCLUSIONS: R0-1 re-resection was newly identified as a prognostic factor after re-resection, in addition to non-thymic carcinoma histological classification and longer recurrence-free intervals, as documented in the initial report.

Development of a machine learning-based risk model for postoperative complications of lung cancer surgery.

PURPOSE: To develop a comorbidity risk score specifically for lung resection surgeries. METHODS: We reviewed the medical records of patients who underwent lung resections for lung cancer, and developed a risk model using data from 2014 to 2017 (training dataset), validated using data from 2018 to 2019 (validation dataset). Forty variables were analyzed, including 35 factors related to the patient's overall condition and five factors related to surgical techniques and tumor-related factors. The risk model for postoperative complications was developed using an elastic net regularized generalized linear model. The performance of the risk model was evaluated using receiver operating characteristic curves and compared with the Charlson Comorbidity Index (CCI). RESULTS: The rate of postoperative complications was 34.7% in the training dataset and 21.9% in the validation dataset. The final model consisted of 20 variables, including age, surgical-related factors, respiratory function tests, and comorbidities, such as chronic obstructive pulmonary disease, a history of ischemic heart disease, and 12 blood test results. The area under the curve (AUC) for the developed risk model was 0.734, whereas the AUC for the CCI was 0.521 in the validation dataset. CONCLUSIONS: The new machine learning model could predict postoperative complications with acceptable accuracy. CLINICAL REGISTRATION NUMBER: 2020-0375.

Evolution of Three-Dimensional Computed Tomography Imaging in Thoracic Surgery.

Radiologic reconstruction technology allows the wide use of three-dimensional (3D) computed tomography (CT) images in thoracic surgery. A minimally invasive surgery has become one of the standard therapies in thoracic surgery, and therefore, the need for preoperative and intraoperative simulations has increased. Three-dimensional CT images have been extensively used, and various types of software have been developed to reconstruct 3D-CT images for surgical simulation worldwide. Several software types have been commercialized and widely used by not only radiologists and technicians, but also thoracic surgeons. Three-dimensional CT images are helpful surgical guides; however, in almost all cases, they provide only static images, different from the intraoperative views. Lungs are soft and variable organs that can easily change shape by intraoperative inflation/deflation and surgical procedures. To address this issue, we have developed a novel software called the Resection Process Map (RPM), which creates variable virtual 3D images. Herein, we introduce the RPM and its development by tracking the history of 3D CT imaging in thoracic surgery. The RPM could help develop a real-time and accurate surgical navigation system for thoracic surgery.

Bronchial occlusion with endobronchial Watanabe spigots using a two-scope technique for massive haemoptysis.

Massive haemoptysis is a life-threatening condition whose cause needs to be identified rapidly so that prompt interventions can ensue. Bronchial occlusion with endobronchial Watanabe spigots (EWSs) may be useful when endovascular treatment or surgery proves to be difficult. An 84-year-old woman developed massive haemoptysis during percutaneous mitral valve repair for refractory heart failure due to severe mitral regurgitation (MR). Interventional radiology (IVR) and surgery were contraindicated, and bronchial occlusion with EWSs was attempted to control bleeding. The bleeding was so persistent that it was difficult to secure the visual field without aspiration with a bronchoscope. Herein, we report a two-scope technique, also used in cryobiopsy of peripheral lung lesions, to control bleeding and perform bronchial occlusion with EWSs.

A Case of Incidentally Discovered Congenital Complete Pericardial Defect during Lobectomy for Lung Cancer: A Case Report and Literature Review.

An 82-year-old male patient underwent a left upper lobectomy with anterolateral thoracotomy for lung cancer. Although a complete left-pericardial defect was observed during surgery, the pericardial repair was not performed because the left lower lobe remained and the heart was considered stable. Postoperative pathological examination revealed primary synchronous double-lung squamous-cell carcinoma (pathological stage pT2a(2)N0M0 stage IB). He was discharged without complications on postoperative day 8. Leftward displacement of the heart and left diaphragmatic elevation, suspected of phrenic-nerve paralysis, were found in the chest X-ray after discharge. However, the patient's overall condition remained unaffected at the 5-month postoperative follow-up. To assess the need for pericardial repair, we compared cases of complete pericardial defects observed during lobectomy or pneumonectomy reported in the literature. Only one of 12 cases occurred postoperative death despite pericardial repair, and that case combined pectus excavatum and pericardial defects. Our assessment indicated that pericardial repair might not be necessary, excluding complex cases.

The Tumor Immune Microenvironment Is Associated With Recurrence in Early-Stage Lung Adenocarcinoma.

Introduction: Immune checkpoint inhibitors have recently been approved for the treatment of early-stage NSCLC in the perioperative setting on the basis of phase 3 trials. However, the characteristics of such patients who are susceptible to recurrence after adjuvant chemotherapy or who are likely to benefit from postoperative immunotherapy have remained unclear. Methods: This biomarker study (WJOG12219LTR) was designed to evaluate cancer stem cell markers (CD44 and CD133), programmed death-ligand 1 (PD-L1) expression on tumor cells, CD8 expression on tumor-infiltrating lymphocytes, and tumor mutation burden in completely resected stage II to IIIA NSCLC with the use of archived DNA and tissue samples from the prospective WJOG4107 trial. Tumors were classified as inflamed or noninflamed on the basis of the PD-L1 tumor proportion score and CD8+ tumor-infiltrating lymphocyte density. The association between each potential biomarker and relapse-free survival (RFS) during adjuvant chemotherapy was assessed by Kaplan-Meier analysis. Results: A total of 117 patients were included in this study. The median RFS was not reached (95% confidence intervals [CI]: 22.4 mo-not reached; n = 39) and 23.7 months (95% CI: 14.5-43.6; n = 41) in patients with inflamed or noninflamed adenocarcinoma, respectively (log-rank p = 0.02, hazard ratio of 0.52 [95% CI: 0.29-0.93]). Analysis of the combination of tumor inflammation category and TP53 mutation status revealed that inflamed tumors without TP53 mutations were associated with the longest RFS. Conclusions: PD-L1 expression on tumor cells, CD8+ T cell infiltration, and TP53 mutation status may help identify patients with early-stage NSCLC susceptible to recurrence after adjuvant chemotherapy.

Lung cancer after kidney transplantation: a 50-year experience at a single institution.

PURPOSE: To investigate the clinical characteristics of lung cancer that develops after kidney transplantation. METHODS: The clinical data of patients with lung cancer diagnosed after kidney transplantation were collected retrospectively. The medical records were extracted from our database. All patients underwent routine chest examination after kidney transplantation. RESULTS: In total, 17 lung tumors were detected in 15 (0.6%) of 2593 patients who underwent kidney transplantation at our institution. Eleven lung tumors were completely resected from a collective 10 patients (surgical group). The remaining five patients did not receive surgical treatment (nonsurgical group). The surgical group underwent wedge resection (n = 5), segmentectomy (n = 1), lobectomy (n = 3), and bilobectomy (n = 1). The pathological stages were 0 (n = 1), IA1 (n = 2), IA2 (n = 4), IA3 (n = 2), and IB (n = 1). The surgical group had a significantly better prognosis than the nonsurgical group. There were no perioperative complications related to kidney transplantation in either group. CONCLUSIONS: Routine chest examination would be useful for the early diagnosis and treatment of lung cancer after kidney transplantation. Moreover, surgical resection for early-stage lung cancer was associated with a better prognosis for kidney transplantation patients.

CHST4 Gene as a Potential Predictor of Clinical Outcome in Malignant Pleural Mesothelioma.

Malignant pleural mesothelioma (MPM) develops primarily from asbestos exposures and has a poor prognosis. In this study, The Cancer Genome Atlas was used to perform a comprehensive survival analysis, which identified the CHST4 gene as a potential predictor of favorable overall survival for patients with MPM. An enrichment analysis of favorable prognostic genes, including CHST4, showed immune-related ontological terms, whereas an analysis of unfavorable prognostic genes indicated cell-cycle-related terms. CHST4 mRNA expression in MPM was significantly correlated with Bindea immune-gene signatures. To validate the relationship between CHST4 expression and prognosis, we performed an immunohistochemical analysis of CHST4 protein expression in 23 surgical specimens from surgically treated patients with MPM who achieved macroscopic complete resection. The score calculated from the proportion and intensity staining was used to compare the intensity of CHST4 gene expression, which showed that CHST4 expression was stronger in patients with a better postoperative prognosis. The median overall postoperative survival was 107.8 months in the high-expression-score group and 38.0 months in the low-score group (p = 0.044, log-rank test). Survival after recurrence was also significantly improved by CHST4 expression. These results suggest that CHST4 is useful as a prognostic biomarker in MPM.