Thymic Epithelial Tumors Research Articles

Machine learning models from computed tomography to diagnose thymic epithelial tumors requiring combined resection.

Minimally invasive approaches have been a standard choice of surgery for noninvasive thymic epithelial tumors (TETs), but we sometimes experience cases requiring combined resection of adjacent structures. We develop and validate machine learning models to predict combined resection based on preoperative contrast-enhanced computed tomography (CT). This study included 212 patients with TETs (140 in the training cohort and 72 in the validation cohort) who underwent radical surgery. Radiomics features were extracted from contrast-enhanced CT and predicted with five feature selection methods and seven machine learning models in nested cross validation. The clinical utility of the models was analyzed by a decision curve analysis (DCA). Fifty-five patients in the training cohort and 28 in the validation cohort required combined resection. The classifiers random forest (RF), gradient boosting (GB), and eXtreme Gradient Boosting (XGB) indicated high predictive performance, with the XGB classifier based on features selected by GB performing the best, with an area under the curve (AUC) of 0.797. In the validation cohort, the classifier had an AUC of 0.817. The DCA showed the validity of the model with a threshold range of 15-72%. When restricted to combined pulmonary and pericardial resection, the respective AUCs were 0.736 and 0.674 for the training cohort and 0.806 and 0.924 for the validation cohort. The machine learning model based on preoperative CT images was able to diagnose TETs requiring combined resection with high accuracy. The DCA demonstrated a wide range of model validity and may aid in surgical approach selection.

3121: Coronary arteries exposure in VMAT versus 3D conformal radiotherapy for thymic epithelial tumors

3121: Coronary arteries exposure in VMAT versus 3D conformal radiotherapy for thymic epithelial tumors

Depiction of the Genetic Alterations and Molecular Landscapes of Thymic Epithelial Tumors: A Systematic Review and Meta-Analysis.

Thymic epithelial tumors (TETs), consisting of thymomas, thymic carcinomas (TCs), and thymic neuroendocrine tumors, are rare diseases. Surgery remains the prime option in resectable and early-stage TETs, while chemotherapy, targeted therapy, and immunotherapy are also potential treatment modalities. However, the inadequate comprehension of the molecular landscape of TETs impedes the exploitation of such therapies. Hence, we conducted a meta-analysis which includes 21 studies reporting on genomic alterations in TETs and 14 studies reporting on PD-L1 expression levels, respectively. The pooled estimated rates of the most frequently mutated genes and PD-L1 expression levels were analyzed using the R software. We uncovered that the pooled estimated overall mutation rate is 0.65 ([0.49; 0.81]), and the top three genes with highest mutation frequency in thymomas and TCs are GTF2I (0.4263 [0.3590; 0.4936]), TP53 (0.1101 [0.0000; 0.2586]), and RAS (0.0341 [0.0104; 0.0710]), and TP53 (0.1797 [0.0732; 0.3203]), CDKN2A (0.0608 [0.0139; 0.1378]), and TET2 (0.0318 [0.0087; 0.0639]), respectively. A uniform GTF2I mutational rate in thymomas and TP53 mutational rate in thymic squamous cell carcinomas (TSCCs) are also observed. The pooled estimated expression level of PD-L1 is 0.71 ([0.59-0.81]). This systematic review provides an overview of the gene alteration landscape and PD-L1 expression levels in TETs, discovers several potential confounding factors that may contribute to the high heterogeneity, and facilitates deeper investigations into the elucidation of the molecular landscape of TETs.

ACTN4 is associated with the malignant potential of thymic epithelial tumors through the β-catenin/Slug pathway.

Thymic epithelial tumors (TETs) are rare tumors arising from the mediastinum. Among TETs, thymoma type B2, B3 and thymic carcinoma are highly malignant and often present invasion and dissemination. However, the biological characteristics of TETs have not been thoroughly studied, and their mechanisms of invasion and dissemination are largely unknown. α-Actinin 4 (ACTN4) is a member of actin-binding proteins and reportedly plays important roles in the progression of several cancers. In this study, we investigated the relationship between ACTN4 and characteristics of the malignant potential of TETs, such as invasion and dissemination. In vitro experiments using Ty-82 thymic carcinoma cells revealed that overexpression of ACTN4 enhanced the proliferative and invasive ability of Ty-82 cells; conversely, knockdown of ACTN4 attenuated the proliferative and invasive potential of Ty-82 cells. In western blotting (WB) experiments, ACTN4 induced the phosphorylation of extracellular signal-regulated kinase and glycogen synthase kinase 3β to regulate the β-catenin/Slug pathway. Furthermore, WB analysis of cancer tissue-origin spheroids from patients with TETs showed results similar to those for Ty-82 cells. Invivo experiments showed that the knockdown of ACTN4 significantly suppressed the dissemination of Ty-82 cells. A WB and immunohistochemistry staining comparison of primary and disseminated lesions of TETs using surgical specimens showed upregulated expression of ACTN4, β-catenin, and Slug proteins in disseminated lesions. In summary, our study suggests ACTN4 is associated with malignant potential characteristics such as invasion and dissemination in TETs via the β-catenin/Slug pathway.

First experience of thoracoscopic thymectomy from a uniportal subxiphoid approach

Purpose of the study. Evaluation of the immediate results of using the subxiphoid approach in patients with non-invasive epithelial thymic tumors. Materials and methods. The experience of treatment of 14 patients who underwent thoracoscopic thymectomy using a single subxiphoid approach for non-invasive epithelial thymic tumors was analyzed. The age of the patients ranged from 24 to 70 years, the median was 42 years. There were 9 (64.3%) women, 5 (35.7%) men. All patients were diagnosed with stage I of the disease at the time of surgical treatment. The minimum size of the removed thymoma in the study was 15 mm, the maximum was 65 mm, and the median was 38 mm. Results. Two operations (14.3%) were associated with technical difficulties due to the presence of adhesions after previous pneumonia, which led to more pronounced intraoperative blood loss, which amounted to 200 ml. The duration of the operation varied from 60 to 180 minutes, the median being 82.5 minutes. In most cases (97.6%), the level of pain did not exceed 4 points on the visual analog pain scale (VAS). In the postoperative period, a surgical complication was observed - the formation of a retrosternal hematoma; there were no deaths. Conclusion. Performing thoracoscopic thymectomy from a single subxiphodal approach is a reasonable option for non-invasive Tet’s. This method allows you to perform the operation in full, without violating oncological principles. It has been proven that for tumors up to 65 mm in size, this technique does not lead to an increase in the duration of the operation and an increase in intraoperative complications.

Immunohistochemistry for YAP1 N-terminus and C-terminus highlights metaplastic thymoma and high-grade thymic epithelial tumors by different staining patterns.

Metaplastic thymoma (MT), a rare subtype of thymic epithelial tumors (TETs), harbors YAP1::MAML2 fusions. Poroma, a skin tumor, also carries these fusions and exhibits a unique staining pattern for YAP1 immunohistochemistry (IHC), namely, a YAP1 N-terminus (YAP1[N])-positive but YAP1 C-terminus (YAP1[C])-negative pattern. In this context, MT was recently reported to lack YAP1(C) expression exclusively among TET subtypes. However, a lack of information about YAP1(N) expression in that study and another report that wild-type YAP1 expression was diminished in type B3 thymoma and thymic carcinoma warrants further studies for YAP1 expression in TETs. Thus, we immunohistochemically examined YAP1(N) and YAP1(C) staining patterns in our TET samples, including 14 cases of MT. In addition, 11 of the 14 MT cases were genetically analyzed with the formalin-fixed paraffin-embedded tissues if they harbored YAP1::MAML2 fusions. MT consistently exhibited YAP1(N)-positive and YAP(C)-negative staining, whereas type B3 thymoma and thymic carcinoma showed relatively heterogeneous staining patterns for YAP1(N) and YAP1(C) and were sometimes negative for both antibodies. Furthermore, a lower expression of YAP1 was found in type B3 compared to B2 thymomas. Among genetically analyzed 11 MT cases, 6 cases showed YAP1::MAML2 fusions, whereas the analysis failed in 5 very old cases due to poor RNA quality. These results indicate that IHC of both YAP1(N) and YAP1(C) is recommended to obtain staining patterns almost unique to MT. The biological significance of YAP1 in high-grade TETs warrants further investigation.

Development and Validation of a CT-Radiomics Nomogram for the Diagnosis of Small Prevascular Mediastinal Nodules: Reducing Nontherapeutic Surgeries

Rationale and ObjectivesThe preoperative diagnosis of small prevascular mediastinal nodules (SPMNs) presents a challenge, often leading to unnecessary surgical interventions. Our objective was to develop a nomogram based on preoperative CT radiomics features, serving as a non-invasive diagnostic tool for SPMNs. Materials and MethodsPatients with surgically resected SPMNs from two medical centers between January 2018 and December 2022 were retrospectively reviewed. Radiomics features were extracted and screened from preoperative CT images. Logistic regression was employed to establish clinical, radiomics, and hybrid models for differentiating thymic epithelial tumors (TETs) from cysts. The performance of these models was validated in both internal and external test sets by area under the receiver operating characteristic curve (AUC), while also comparing their diagnostic capability with human experts. ResultsThe study enrolled a total of 363 patients (median age, 53 years [IQR:45-59 years]; 175 [48.2%] males) for model development and validation, including 136 TETs and 227 cysts. Lesions' enhancement status, shape, calcification, and rad-score were identified as independent factors for distinction. The hybrid model demonstrated superior diagnostic performance compared to other models and human experts, with an AUC of 0.95 (95% CI:0.92-0.98), 0.94 (95% CI:0.89-0.99), and 0.93 (95% CI:0.83-1.00) in the training set, internal test set, and external test set respectively. The calibration curve of the model demonstrated excellent fit, while decision curve analysis underscored its clinical value. ConclusionThe radiomics-based nomogram effectively discriminates between the most prevalent types of SPMNs, namely TETs and cysts, thus presenting a promising tool for treatment guidance.

The influence of PD-L1 expression levels on the efficacy of combination therapy in thymic epithelial tumors.

The significant expression of PD-L1 in thymic epithelial tumors (TETs) has been confirmed, and immunotherapy and its combination therapy have been effective in TETs. However, there is no present evidence that the expression levels of PD-L1 affects the efficacy of combination therapy. Our study aimed to shed light on this relationship. Patients with thymic epithelial tumors (TETs) from multicenter hospitals were retrospectively identified. Objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAEs) in 22 patients were included. We divided the patients the 22 patients with PD-L1 test into three levels (high expression, low expression and no expression) and analyzed the relationship between the levels of PD-L1 expression and the efficacy of combination therapy. Combination therapy showed an effective benefit in 22 patients with TETs, the median PFS (mPFS) was 16 months (95% CI: 8.5-23.5) and the median OS (mOS) was 38 months (95% CI: 21.5-54.5). Cox-regressive analysis found whether PD-L1 expression affected the PFS of patients (p = 0.017). Among the patients with PD-L1 expression, the levels of expression were correlated with curative effect (Kruskal-Wallis test, PFS: P = 0.012; OS: P = 0.01), and high expression group was along with better efficacy than low expression (Wilcoxon test, P = 0.01). Moreover, in 17 patients treated with immunotherapy combined with chemotherapy, the expression of PD-L1 was also associated with efficacy (Kruskal-Wallis test, p = 0.021). PD-L1 expression affects the PFS of patients. High expression of PD-L1 patients with TETs responded better to combination therapy, which could provide a therapeutic option in clinic. Besides, other targeted treatments should be considered.

Thymoma resection and myasthenia gravis: what is the neurological outcome in patients older than 65years?

To increase the neurological results in patients older than 65years with myasthenia gravis after thymectomy, we retrospectively analysed this outcome in a large bicentric cohort of patients with myasthenia gravis (MG)years, for which surgery was indicated for a concurrent thymoma. From 1/2000 to 2/2022, 502 patients underwent thymectomy for thymic epithelial tumours (TETs) in two high-volume Institutions (167aged more than 65years). Among them, 66 patients were affected by TET and MG, representing our final study group. The mean age for MG onset was 68.3 ± 6years.At surgery, the Osserman score 2 was the most diffuse in our cohort (43, 65.1%), followed by 1 (20, 30.3%). In 11 cases, the MG diagnosis coincided with thymoma diagnosis. In the other cases, the interval between MG diagnosis and surgery was 1.7years ± 1.9. The most common surgical approach was sternotomy (41,62.1%), followed by RATS (14,21.2%). The most frequent TNM stage was T1N0 (75.7%) and most patients had WHO type-B tumour. After radical thymectomy, 58 patients (88%) reported a significant neurological improvement. According to MGFA-PIS, after surgery we had 4 (6%) complete stable remission, 11 (16.7%) pharmacological remission, 43 (65.2%) minimal manifestation, 2 (3%) worsening/death for MG, and 5 (7.6%) unchanged. No association was found between neurological outcome and age of MG onset, kind of pharmacological therapy before surgery, surgical approach (sternotomy vs others), tumour dimension, the ITMIG stage and the preoperative Osserman score. For MG and thymoma-afftected patients over 65years, thymectomy seems to be an effective treatment to improve neurological symptoms. We suggest to set up clinical trials to explore the neurological efficacy of mini-invasive thymectomy in clinically selected MG patients aged over 65years.

Thymic MALT lymphoma associated with Sjögren’s syndrome with postoperative cardiac tamponade and acute pleuritis: a case report

BackgroundThymic mucosa-associated lymphoid tissue (MALT) lymphoma is rare and is known to be associated with Sjögren’s syndrome (SjS). SjS is rarely accompanied by serositis. Here, we describe the first case of postoperative cardiac tamponade and acute pleuritis in a patient with thymic MALT lymphoma associated with SjS.Case presentationA 33-year-old woman with SjS presented with an anterior mediastinal mass on chest computed tomography, which was performed for further examination of the condition. Suspecting a thymic MALT lymphoma or thymic epithelial tumor, total thymectomy was performed. The mediastinal mass was histopathologically diagnosed as a thymic MALT lymphoma. The patient was discharged with a good postoperative course but visited the hospital 30 days after surgery for dyspnea. Cardiac tamponade was observed and drainage was performed. Four days after pericardial drainage, chest radiography revealed massive left pleural effusion, and thoracic drainage was performed. The patient was diagnosed with serositis associated with SjS and treated with methylprednisolone, which relieved cardiac tamponade and pleuritis.ConclusionsSurgical invasion of thymic MALT lymphomas associated with SjS may cause serositis. Postoperative follow-up should be conducted, considering the possibility of cardiac tamponade or acute pleuritis due to serositis as postoperative complications.

COVID-19 in patients with thymic epithelial tumors with or without Good’s syndrome: a single-center retrospective study

IntroductionThymic epithelial tumors (TETs) are rare neoplasms often associated with immune-related disorders. Patients with Good’s syndrome (GS), an adult-acquired TET-related immunodeficiency, are at a high risk of mortality due to infectious diseases. This study aims to examine COVID-19 occurrence and severity in TET patients, with or without GS.MethodsClinical records of TET patients referred to the Regional Coordinating Center for Rare Tumors of Campania Region were retrospectively collected. During the observation period, elapsing from March 2020 to April 2023, the following data were collected: occurrence of SARS-CoV-2 infection; COVID-19 severity, according to the National Institute of Health (NIH) illness categories; COVID-19 treatment. COVID-19 occurrence and severity were assessed in the overall population and correlated with the presence of GS and/or other immune-related dysregulations.ResultsOverall, 47 TET patients were included in the study; 27 of these (57.4%) had GS. All participants had received a full cycle of mRNA vaccine for SARS-CoV2., Thirty-one patients (66.0%) experienced COVID-19, of whom 18 (58.0%) had previously received a diagnosis of GS. No significant association of GS and/or other immune-related dysregulations with SARS-CoV-2 infection occurrence was detected (Fisher’s exact test p = 1 and p = 0.3587, respectively). Among patients with GS, 8 (45.0%) reported a COVID-19 severity score of ≥ 3; whereas, only 1 of the 13 patients without GS (7.7%) had a severity score of ≥ 3. The correlation between presence of GS and COVID-19 severity (score 1 or 2 vs. ≥ 3) was statistically significant (p = 0.0448). No statistically significant association between COVID-19 severity and other immune-related syndromes were found (p = 1). Of note, all the hospitalized patients for NIH 4 and 5 COVID-19 had GS.ConclusionsOur data suggest that TET patients, especially those with GS, require a careful multidisciplinary monitoring for SARS-CoV-2 infection, in order to establish tailored treatments and prophylactic protocols.

Expression of vascular endothelial growth factor receptor in thymic epithelial tumors

Expression of vascular endothelial growth factor receptor in thymic epithelial tumors

Updated Outcomes of Surgical Treatment for Recurrent Thymic Tumor: A Report from the Japanese Nationwide Database.

This study aimed to analyze the surgical outcomes for recurrent thymic epithelial tumors and identify the factors associated with post-recurrence survival, using an updated Japanese nationwide database. The cohort that developed recurrence after the initial resection was extracted from an updated database of patients whose thymic epithelial tumors 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. 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. 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.

Extended-sleeve resection for endoluminal recurrence of B3 thymoma: does aerogenous spread really exist?

Thymomas are a variant of thymic epithelial tumours. They are considered malignant due to their tendency to local invasion and they showed lower metastatic behaviour. Distal metastasis is rare and an endobronchial mass is a rare presentation. First-line treatment for early-stage thymomas is surgery; for Masaoka-Koga stage III, neoadjuvant or adjuvant chemoradiation therapy should be considered in association with surgery after Multidisciplinary Tumour Board evaluation. We report a rare case of radical resection with type A extended-sleeve lobectomy in a 63-year-old woman who was affected by endobronchial recurrence of B3 thymoma, 31 months after complete and radical thymectomy.

China Anti-Cancer Association Guidelines for the diagnosis, treatment, and follow-up of thymic epithelial tumors (2023).

Thymic epithelial tumors (TETs) are a relatively rare type of thoracic tumors with higher incidence in Asians. The diagnosis and treatment pattern has long been based mainly on clinical experience and expert consensus. In recent years, with an increasing number of TETs detected in physical examinations, there is an urgent need to develop the guidelines that apply to the Chinese population. Thus, we intend to develop a holistic integrative guideline for TETs. Under the leadership of the Chinese Anti-Cancer Association (CACA) Mediastinal Tumor Committee, a multidisciplinary guideline development group was established. Systemic literature review and two rounds of questionnaires regarding key clinical issues were carried out. The grading of recommendations assessment, development and evaluation (GRADE) approach was used to rate the quality of evidence and the strength of recommendations. The CACA guideline provides recommendations for the clinical differential diagnosis of anterior mediastinal lesions, management of asymptomatic small anterior mediastinal nodules, pathological classification and staging systems of TETs, as well as principles of surgery, neoadjuvant and adjuvant therapies, systemic therapies for advanced TETs, and follow-up strategies after surgical resection. This guideline provides holistic integrative management strategies for TETs and would be a useful tool for clinicians on decision-making.

Surgical treatment of thymic epithelial tumors: a narrative review.

Thymic epithelial tumors (TETs) are scarce neoplasms of the prevascular mediastinum. Included in this diverse category of lesions are thymomas and thymic carcinomas (TCs). Surgery is the mainstay of treatment of tumors that are deemed resectable. However, up till now, optimal surgical access has been a subject of debate. The advent of new techniques, such as video-assisted thoracoscopic surgery (VATS) and robotic-assisted thoracoscopic surgery (RATS), challenged the median sternotomy which was traditionally considered the access of choice. This review aims to demonstrate the current evidence concerning the surgical treatment of TET and to enlighten other controversial issues about surgery. PubMed research was conducted using the terms [surgery] AND [thymic epithelial tumors] OR [thymomas] and [surgical treatment] AND [thymic epithelial tumors] OR [thymomas]. Papers concerning pediatric cases and non-English literature papers were excluded. Individual case reports were also excluded. Minimally invasive surgical techniques (MIST) such as VATS and RATS are increasingly applied in early-stage TET. Although numerous published studies have demonstrated better perioperative outcomes in early-stage TET, long-term follow-up data are still required to demonstrate the oncological equivalent of MIST to open surgery. Resection of stage III TET is more challenging. Thymectomy can be expanded en bloc to include the major vascular structures, lung, pleura, phrenic, or vagus nerve in these individuals. There is no agreement on the ideal surgical access and traditionally these patients underwent open sternotomy, sometimes combined with a thoracic access. Evidence concerning the treatment of stage IVA disease is mainly derived from retrospective case series which are highly heterogeneous in terms of the number of enrolled patients, histology, degree of pleural involvement, and timing of presentation. New techniques in the field of minimally invasive surgery are gaining acceptance for early-stage TET but longer follow-up periods are warranted to prove their oncological outcomes. On the contrary, these techniques should be used cautiously in case of locally advanced tumors. Surgeons must not forget that the main objective is the complete resection of the lesion, which is one major predictive factor for increased survival.

Update on thymic epithelial tumors: a narrative review.

Thymoma, thymic carcinoma and thymic neuroendocrine tumors originate from the epithelial cells of the thymus and account for the thymic epithelial tumors (TETs). Although TETs are uncommon, they are the most frequent tumor type in the anterior mediastinum. Multidisciplinary approach is essential for their correct management. The aim of the present review is to summarize the update management for TETs. For this review, we searched in Excerpta Medica database (EMBASE) and MEDLINE until 6 September 2023. The terms used in the search included thymoma, thymic carcinoma, thymic epithelial tumors, management, immunotherapy, multiple tyrosine kinases inhibitors. The therapeutic approach is based on histology and tumor stage and may involve surgery with or without neoadjuvant or adjuvant treatment. In the metastatic setting, platinum-based chemotherapy is the standard of care and patients who do not respond to first-line treatment have limited treatment options mainly because of the poor efficacy shown in subsequent lines of therapy. Future research should focus on identifying predictive biomarkers for patients with TETs, and should implement multicenter collaborations and appropriate clinical trials tailored for rare tumor types. Immune check point inhibitors, mammalian target of rapamycin (mTOR) and antiangiogenic multikinase inhibitors have also been studied in this clinical setting.

Tislelizumab combined with chemotherapy in advanced thymic tumors.

e20139 Background: Thymic tumors refer to tumors derived from thymic epithelial cells, including thymoma and thymic carcinoma. Most cases in advanced stages when detected, and treatment is still controversial. Since 2018, immunotherapy has gradually been used for a variety of solid tumors and the curative efficacy has been notable. The efficacy of immunotherapy is increasingly improved with the increased expression of programmed death-ligand 1 (PD-L1) by tumor cells. The thymus is an immune-rich organ. PD-L1 expression ranges from 23% to 92% in thymoma, and from 36% to 100% in thymic carcinoma. Thus, immunotherapy has been implicated as having broad prospects in the treatment of thymic tumors. Tislelizumab is an inhibitor of PD-1, which has shown preliminary anti-tumor effects in various solid tumors. The combination of immunotherapy and chemotherapy has produced excellent anti-tumor activity for various types of tumors. However, there is a lack of clinical trial data to support the application of tislelizumab for the treatment of advanced thymic tumors. In this article, the efficacy and safety of tislelizumab combined with chemotherapy were analyzed in eight patients with advanced thymic tumors to provide data for the use of this monoclonal antibody as first-line treatment of advanced thymic tumors. Methods: Here, after obtaining fully informed consent, we report cases involving eight patients with advanced thymic tumors treated with tislelizumab combined with chemotherapy. The clinical characteristics, lesion changes, treatment process, drugs used, drug efficacy, complications or adverse reactions were recorded and followed up to evaluate the efficacy and safety of tislelizumab combined with chemotherapy in the treatment of advanced thymic tumors. Results: This article reports eight cases of advanced thymic tumor treated with tislelizumab combined with chemotherapy. Two patients received tislelizumab combined with chemotherapy as first-line treatment, and the remaining six patients were treated with tislelizumab after poor response to chemotherapy. Five patients achieved a partial response to the combined treatment. Of these, the partial response was retained in three patients after switching to tislelizumab monotherapy. The remaining three patients displayed stable disease after the combined treatment. There were no serious immune-related adverse events during treatment. The side effects of tislelizumab combined with chemotherapy were well tolerated. Conclusions: No clinical study of immunotherapy combined with standard chemotherapy as first-line treatment for advanced unresectable or metastatic thymic epithelial tumors has been described. This article provides strong evidence for the early application or even first-line use of tislelizumab combined with chemotherapy for advanced thymic epithelial tumors. More clinical studies are needed to evaluate the efficacy and safety of tislelizumab in thymic tumors.

Enhancing thoracic oncology in Armenia: Impact of the implementation of an expert-guided virtual multidisciplinary tumor board.

e13808 Background: The importance of expert-guided multidisciplinary tumor boards (MDTs) in the management of patients with complex malignancies is well established. Modern global telecommunication platforms allow for holding specialized virtual MDT discussions led by international experts even in limited-resource settings. The creation of such a group is of high importance for Armenia given the high incidence and increasing complexity of thoracic malignancies. We describe the initial impact of the implementation of the Thoracic Tumors Working Group (TTWG) of Armenia from August 2022 through January 2024. Methods: The TTWG of Armenia is an MDT comprised of medical oncologists, radiation oncologists, thoracic surgeons, pathologists, and radiologists. The group was formed under the Immune-Oncology Research Institute in August 2022 to discuss the management of patients with complicated thoracic malignancies. For each case, the clinical history, imaging, pathologic findings, and patient management plans are discussed. Updates on treatment paradigms and ongoing clinical trials are also reviewed. The MDTs are held biweekly via the Zoom platform under the supervision of international experts in thoracic oncology. Recordings of MDTs were reviewed to retrospectively identify case characteristics and the impact on patient management. Results: From August 2022 through January 2024, 89 cases were discussed during 33 TTWG MDTs. On average, each MDT was attended by 14 physicians and trainees in Armenia, and by two international experts in thoracic medical and radiation oncology. Median meeting length was 55 minutes with a median of 3 cases presented. Diagnoses included lung adenocarcinoma (n=31, 37.3%), squamous cell lung carcinoma (n=15, 18.0%), neuroendocrine tumors (n=16, 19.3%), small cell lung cancer (n=16, 19.3%), and thymic epithelial tumors (n=6, 7.3%). All disease stages were represented: I 3.7%, II 4.9%, III 31.7%, and IV 47.9%. The male-to-female ratio was 3.6:1 and the median age was 63 years (range: 29-76). Based on MDT discussion, the pre-MDT diagnosis was confirmed in 95.5% (n=85) of patients with down-staging in 3.4% (n=3). The proposed pre-MDT treatment plan was significantly altered in 42.7% (n=38) of patients. Additional studies, mainly PET/CT, bronchoscopy, and broader molecular profiling were recommended for 29.2% (n=26) of patients. Follow-up discussions were held for 7.9% (n=7) of patients based on information arising from prior MDT discussions. The TTWG of Armenia continues to be active. Conclusions: Our initial data suggest that the TTWG of Armenia has had a meaningful influence on patient management by providing access to specialty-expert care and physician education. The impact on patient outcomes will continue to be assessed. The TTWG of Armenia can serve as a model to improve outcomes in other resource-limited settings.

Somatostatin analogues in the management of thymic epithelial tumors: A retrospective, single-center study.

Somatostatin analogues in the management of thymic epithelial tumors: A retrospective, single-center study.