Treatment Of Thymic Epithelial Tumors Research Articles

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.

What Have We Learned from Molecularly Informed Clinical Trials on Thymomas and Thymic Carcinomas-Current Status and Future Directions?

Thymic epithelial tumors (TETs), which include thymomas and thymic carcinomas, are a rare, heterogeneous group of malignancies that originate from the thymus gland. As an important organ of immune cell development, thymic tumors, particularly thymomas, are often associated with paraneoplastic autoimmune disorders. The advances in targeted therapies for both solid and hematologic malignancies have resulted in improved patient outcomes, including better and more durable efficacy and improved toxicity. Targeted therapies have also been investigated in the treatment of TETs, though the results have largely been modest. These have included somatostatin-receptor-targeting therapies, KIT- and EGFR-directed tyrosine kinase inhibitors, epigenetic modulators, anti-angiogenesis agents, and agents targeting the cell proliferation and survival pathways and cell cycle regulators. Numerous investigated treatments have failed or underperformed due to a lack of a strong biomarker of efficacy. Ongoing trials are attempting to expand on previous experiences, including the exploration of effective drugs in early-stage disease. Novel combination therapy strategies are also undergoing evaluation, with the goal of augmenting efficacy and understanding the toxicity while expanding the biomarkers of efficacy and safety. With advances in technology to improve target identification and drug delivery, old targets may become new opportunities, and the subsequently developed drugs may find their place in the treatment of thymic tumors.

Long-Term Outcomes in Stage II/III Thymic Epithelial Tumor Patients Treated with Post- Operative Radiotherapy

Thymic epithelial tumors (TETs) are rare malignancies that originate in the anterior mediastinum. Unlike other tumors of the chest, TETs recur most often in the pleura. The primary treatment of early stage TETs is surgical resection, with the role of adjuvant chemotherapy/radiotherapy controversial. Mixed results have been reported as to whether postoperative radiotherapy (PORT) decreases tumor recurrence or time to recurrence, but PORT can cause short-term and long-term toxicity. Therefore, assessing the benefit of PORT is important. For the present retrospective study, we created a database of stage II/III TET patients seen at Simon Cancer Center from 2000-2023 to examine long-term outcomes. Of the 214 stage II/III TET patients that underwent surgery in the database, 67 patients treated with PORT were isolated. Subsequently, 67 patients who did not receive PORT were matched to the PORT population based on similarities in histology, surgical margins, and chemotherapy received. Local vs. distant tumor recurrence, long-term complications, and overall survival were then compared. The PORT population had the following histologic distribution: 3 Type A, 3 Type AB, 47 Type B1/B2/B3, and 14 carcinoma; for the non-PORT population: 8 Type A, 13 Type AB, 36 Type B1/B2/B3, and 10 carcinoma. There were 16 stage IIA, 6 stage IIB, and 45 stage III patients in the PORT population, and 17 stage IIA, 9 stage IIB, and 41 stage III patients in the non-PORT population. The PORT population had 57 recurrences, whereas the non-PORT population had 20 recurrences (p=1.02 x 10-9). The PORT population had 5 deaths and 50 instances of long-term complications, while the non-PORT population had 3 deaths and 25 instances of long-term complications. Overall, these data do not support the routine usage of PORT in resected Stage II/III TET. Further analysis in larger data sets are warranted.

An Overview of the Use of Anti-Angiogenic Agents in the Treatment of Thymic Epithelial Tumors

Angiogenesis significantly influences the carcinogenesis of thymic epithelial tumors (TET). Both thymomas and thymic carcinoma (TC) overexpress VEGF-A and VEGFR-1 and -2. This review aims to provide an appraisal of the use of anti-angiogenics in the treatment of TET. The literature research identified 16 studies that were deemed eligible for further analysis. Seven studies assessed the clinical efficacy of sunitinib and five studies the use of apatinib and/or anlotinib. The multicenter Japanese phase II REMORA trial investigated the efficacy of lenvatinib, which is a multi-targeted inhibitor of VEGFR, FGFR, RET, c-Kit, and other kinases. The objective response rate was 38% (25.6–52%), which is the highest documented in TET that progressed after first-line chemotherapy. Anti-angiogenic agents may be useful in the treatment of TET, which are not amenable to curative treatment. Their toxicity profile seems to be acceptable. However, angiogenesis inhibitors do not appear to have a major influence on either thymomas or TC, although multikinase inhibitors may have some effect on TC. The current evidence suggests that the most active agent is lenvatinib, whereas sunitinib could be proposed as an acceptable second-line therapy for TC. Further research concerning the combination of immune checkpoint inhibitors with anti-angiogenic drugs is warranted.

The Efficacy and Safety of Anlotinib Alone and in Combination with Other Drugs in Previously Treated Advanced Thymic Epithelia Tumors: A Retrospective Analysis.

Thymic epithelial tumors (TETs) are rare thoracic malignancies with no standard second-line treatment. Tumor angiogenesis is closely associated with the pathogenesis and invasiveness of TETs. Anlotinib is a small-molecule multitarget tyrosine kinase inhibitor (TKI) which inhibits tumor angiogenesis and tumor cell proliferation. Published studies have demonstrated the promising clinical effect of multitarget TKIs sunitinib and lenvatinib in previously treated TETs. However, TKIs have a high incidence of adverse events (AEs). In this study, we investigated the clinical efficacy and safety of anlotinib in previously treated TET patients. We collected clinical data of 22 patients from Shandong Cancer Hospital and Institute between October 2018 and March 2022. These patients were diagnosed with advanced TETs and received at least the first-line (1st-line) treatment. We analyzed the clinical effects between anlotinib monotherapy and anlotinib combination therapy in the second-line (2nd-line) or anlotinib treatment in different lines. These 22 patients included 18 cases of thymic carcinoma (TC) and 4 cases of thymoma (T). 68.2% of patients were males, and the median age was 53 years. Fourteen patients (63.6%) received anlotinib monotherapy and 8 patients (36.4%) received anlotinib combination therapy. The objective response rate (ORR) was 9.1% in the overall patients. The median progression-free survival (PFS) in the overall population was 12 months (14 months for T and 9 months for TC), and the median overall survival (OS) was 24 months (survival was not reached for T and was 24 months for TC). The incidence of AEs was 50%, most of them were grades I and II, and the incidence of grades III and IV AEs was 9%. This is the first study reporting the clinical effect of anlotinib in previously treated TETs patients. The survival data indicate that the efficacy of anlotinib is superior to sunitinib and lenvatinib. Our results suggest that anlotinib is a promising treatment option for previously treated TET patients and its toxicity is tolerable. More research and patents are needed in the future to explore better options for the diagnosis and treatment of TETs.

Thymus alterations and susceptibility to immune checkpoint inhibitor myocarditis.

Immune checkpoint inhibitors (ICI) have transformed the therapeutic landscape in oncology. However, ICI can induce uncommon life-threatening autoimmune T-cell-mediated myotoxicities, including myocarditis and myositis. The thymus plays a critical role in T cell maturation. Here we demonstrate that thymic alterations are associated with increased incidence and severity of ICI myotoxicities. First, using the international pharmacovigilance database VigiBase, the Assistance Publique Hôpitaux de Paris-Sorbonne University data warehouse (Paris, France) and a meta-analysis of clinical trials, we show that ICI treatment of thymic epithelial tumors (TET, and particularly thymoma) was more frequently associated with ICI myotoxicities than other ICI-treated cancers. Second, in an international ICI myocarditis registry, we established that myocarditis occurred earlier after ICI initiation in patients with TET (including active or prior history of TET) compared to other cancers and was more severe in terms of life-threatening arrythmias and concurrent myositis, leading to respiratory muscle failure and death. Lastly, we show that presence of anti-acetylcholine-receptor antibodies (a biological proxy of thymic-associated autoimmunity) was more prevalent in patients with ICI myocarditis than in ICI-treated control patients. Altogether, our results highlight that thymic alterations are associated with incidence and seriousness of ICI myotoxicities. Clinico-radio-biological workup evaluating the thymus may help in predicting ICI myotoxicities.

Immunotherapy and Targeted Therapies Efficacy in Thymic Epithelial Tumors: A Systematic Review.

Thymic epithelial tumors (TET) are rare neoplasms of the anterior mediastinum. Surgery is the mainstay treatment for resectable TET, whereas systemic treatments are reserved for unresectable and metastatic tumors. The development of new treatments, such as immune checkpoint inhibitors (ICI) and targeted therapies, with promising results in other types of solid tumors, has led to the investigation of their potential efficacy in TET. The study of tumor microenvironments (TME) is another field of investigation that has gained the interest of researchers. Taking into account the complex structure of the thymus and its function in the development of immunity, researchers have focused on TME elements that could predict ICI efficacy. The primary objective of this systematic review was to investigate the efficacy of ICI in TET. Secondary objectives included the toxicity of ICI, the efficacy of targeted therapies in TET, and the evaluation of the elements of TME that may be predictive factors of ICI efficacy. A literature search was conducted in February 2023 using the Ovid Medline and SciVerse Scopus databases. 2944 abstracts were retrieved, of which 31 were retained for the systematic review. Five phase II and one retrospective study assessed ICI efficacy. The overall response rate (ORR) varied from 0% to 34%. Median progression-free survival (PFS) ranged from 3.8 to 8.6 months, being lower in thymic carcinoma (TC) (3.8-4.2 months). Median overall survival (OS) ranged from 14.1 to 35.4 months. Treatment-related adverse events occurred in 6.6% to 27.3% of patients. Sixteen studies assessed targeted therapies. The most active molecule was lenvatinib, with 38% ORR in patients with TC while no activity was detected for imatinib, erlotinib plus bevacizumab, and saracatinib. Ten studies assessed TME elements that could predict ICI efficacy. Four studies focused on the tumor-infiltrating immune cells suggesting improved outcomes in patients with TC and high tumor-infiltrating lymphocyte densities. Another study showed that CD8+, CD20+, and CD204+ tumor-infiltrating immune cells in cancer stroma might be prognostic biomarkers in TC. Another study identified the immune-related long non-coding RNAs as a predictor of response to ICI. Tumor mutational burden was identified as a predictive factor of ICI efficacy in one study. Despite study heterogeneity, this review shows that ICI could be a therapeutic option for selected patients with TET that are not amenable to curative radical treatment after first-line chemotherapy.

Chinese expert consensus on the diagnosis and treatment of thymic epithelial tumors

Thymic epithelial tumors (TETs) are a relatively rare type of thoracic tumor, accounting for less than 1% of all tumors. The incidence of TETs is about 3.93/10000 in China, slightly higher than that of European and American countries. For resectable TETs, complete surgical resection is recommended. Radiotherapy or chemotherapy may be used as postoperative adjuvant treatment. Treatment for advanced, unresectable TETs consist mainly of radiotherapy and chemotherapy, but there is a lack of standard first- and second-line treatment regimens. Recently, targeted therapies and immune checkpoint inhibitors have shown promising outcomes in TETs. Based on the currently available clinical evidences and the opinions of the national experts, the Thymic Oncology Group of Yangtze River Delta Lung Cancer Cooperation Group (East China LUng caNcer Group, ECLUNG; Youth Committee) established this Chinese expert consensus on the clinical diagnosis and treatment of TETs, covering the epidemiology, diagnosis, treatment, prognosis and follow-up of TETs.

Efficacy and safety of immune checkpoint inhibitors (ICIs) combined with antiangiogenic therapy for thymic epithelial tumors (TETs): a retrospective study.

Immune checkpoint inhibitors (ICIs) combined with antiangiogenic therapy have shown promising antitumor activity against a range of advanced cancers. However, evidence is lacking as to whether this combination therapy could benefit thymic epithelial tumors (TETs). We aimed to explore the efficacy and safety of this combination therapy in advanced TETs. Ten patients with pathologically proven advanced TETs who received ICIs combined with an antiangiogenic agent from 2020 to 2022 at Zhejiang Cancer Hospital were included in the study. The Kaplan-Meier method was used to compare the treatment efficacy and survival outcomes. Of the cohort of ten patients who received immunotherapy combined with antiangiogenic targeting drugs, two patients achieved a partial response (PR) with an objective response rate of 20% and seven patients achieved stable disease (SD) with a disease control rate (DCR) of 90%. The median progression-free survival (PFS) was 6.7 months [95% confidence interval (CI): 3.35-8.515] and the median overall survival (OS) was 45.6 months (95% CI: 3.265-88.001). Grade 3 treatment-related adverse events (TRAEs) were only detected in one patient. No grade 4 or above TRAEs were observed. ICIs in combination with antiangiogenic targeted drugs may be a promising treatment for advanced TETs.

Current and Future Issues in the Surgical Treatment of Thymic Epithelial Tumors: a Review

Current and Future Issues in the Surgical Treatment of Thymic Epithelial Tumors: a Review

Understanding the landscape of immunotherapy in thymic epithelial tumors.

Thymic epithelial tumors (TETs) are a rare group of malignancies arising from the thymus. Surgery remains the foundation of treatment for patients with early-stage disease. Limited treatment options are available for the treatment of unresectable, metastatic, or recurrent TETs and are associated with modest clinical efficacy. The emergence of immunotherapies in the treatment of solid tumors has generated significant interest in understanding their role in TET treatment. However, the high rates of comorbid paraneoplastic autoimmune disorders, particularly in thymoma, have tempered expectations regarding the role of immune-based therapies. Clinical studies of immune checkpoint blockade (ICB) in thymoma and thymic carcinoma have revealed higher frequencies of immune-related adverse events (IRAEs) and limited efficacy. Despite these setbacks, the growing understanding of the thymic tumor microenvironment and systemic immune system has advanced the understanding of these diseases and provided opportunities for novel immunotherapy modalities. Ongoing studies are evaluating numerous immune-based treatments in TETs with the goal of improving clinical efficacy and mitigating IRAE risk. This review will provide insight into the current understanding of the thymic immune microenvironment, outcomes of previous ICB studies, and review treatments currently being explored for the management of TET.

Perspectives on surgical treatment for thymic epithelial tumors: a narrative review.

Thymic epithelial tumors are relatively rare; thus, mostly retrospective studies and a few prospective randomized controlled trials have been conducted on the treatment and the biomarkers, with no standard therapy established. Indications for extended thymectomy, robot-assisted thoracic surgery, and multidisciplinary treatment are controversial. Here, we considered the prospects of surgical treatment and the possibility of immune checkpoint inhibitor (ICI) treatment for thymic epithelial tumors. This is a narrative review; PubMed was searched using a set of keywords related to thymoma and its proposed treatments over the last 5 years. Thymic epithelial tumors are associated with autoimmune diseases. They are relatively rare, and their pathology remains unclear. Therefore, accumulating more case reports is important. Surgical resection is generally considered for both diagnosis and treatment. If the tumor has a strong tendency to invade surrounding areas, such as thymic carcinoma/thymoma, the diagnosis may be confirmed preoperatively by needle biopsy, and induction chemotherapy may be selected. Surgical resection is the most effective treatment, and complete resection is important. In cases where complete resection is difficult, multidisciplinary treatment is performed. Although there are various obstacles, using ICIs may prove effective for treatment both as preoperative and postoperative chemotherapy in the future, as shown for other cancers. Programmed cell death-ligand 1 (PD-L1) is an immunoinhibitory molecule that suppresses T cells activation, leading to tumor progression. Overexpression of PD-L1 in some cancers is associated with poor clinical outcomes. However, the role of PD-L1 expression as a prognostic factor remains controversial. Therefore, various biomarkers other than PD-L1 have been identified. We reviewed the latest treatments for thymic epithelial tumors. If new therapeutic agents such as ICIs and molecular-targeted drugs are developed, this review suggests that surgery will become more important not only as therapy but also as part of multidisciplinary treatment that includes tissue collection.

Balancing the Risk of Adverse Events against the Efficacy of Immunotherapy in Advanced Thymic Epithelial Tumors

Thymic epithelial tumors (TETs) are rare thoracic malignancies with a favorable prognosis when complete surgical resection can be achieved. Therapeutic options for advanced, irresectable, or recurrent disease are limited and currently, a therapeutic standard treatment beyond platinum-based chemotherapy is undefined. Immune checkpoint inhibitors are effective against TETs, however their use is associated with a serious risk of immune-mediated toxicity. In this article, we highlight new insights regarding markers of predictive value for both treatment efficacy and risk of adverse effects in immune checkpoint inhibitor treatment for thymic epithelial tumors.

145P Everolimus for the treatment of thymic epithelial tumors (TETs): A real-world experience

TETs are rare malignancies of the anterior mediastinum ranging from more indolent thymoma (T) to aggressive thymic carcinoma (TC). There is no standard treatment after platinum-based chemotherapy in refractory setting. A phase II trial reported clinical benefit for everolimus (EVE) 10mg (DCR of 88%). EVE has immune modulatory activity, of interest for patients (pts) with auto-immune disorders (AIDs), detected in up to 30% of pts. Few data exist in real-world studies.

Lenvatinib for the treatment of thymic epithelial tumors (TETs): A real-life multicenter experience.

8585 Background: TETs are rare malignancies of the anterior mediastinum being thymoma (T) B3 and thymic carcinoma (TC) the most aggressive subtypes. There is no standard treatment after platinum-based chemotherapy in refractory or metastatic setting. A phase 2 trial has reported clinical benefit for lenvatinib 24mg (objective response rate [ORR] of 38%), a novel multi-targeted inhibitor of VEGFR, FGFR, RET, c-Kit, and other kinases; significant toxicity grade 3 hypertension was 64%. No real-life data exists. Methods: We selected patients (pts) under lenvatinib as a second-line or beyond for refractory TETs from 8 International centers from France (belonging to the nationwide network RYTHMIC) and United States. We analyzed epidemiologic, clinical and pathological characteristics of patients with TET’s. The toxicity was evaluated according to CTCAE v4, with a local evaluation of efficacy and we assessed toxicity profile and survival outcomes. Results: From March 2020 to December 2021, 29 pts were enrolled. Median age at diagnosis was 49 (24-71), 51.7% were women, 6/29 (20.7%) reported auto-immune disorders (AIDs). TC was the most frequent subtype (n=18, 62.1%), followed by B3 and B2. Lenvatinib was used as a second line for 52% of pts, mainly starting from 14 mg/daily (n=20, 69%) and one pts with concomitant pembrolizumab. The ORR was 17% (95%CI 3.0-32.0) with partial responses only seen in TC, and the disease control rate was 76% (95%CI 59.0-92.0). Response was observed with the dose of 24mg in 3 pts and 14mg in 2 pts, with a median follow-up period of 5 months (m) (95%CI 3.2-6.7), PFS at 6 and 12 m was 64% and 30%, respectively. Toxicity is summarized in table 1. Dose de-escalations were needed in 27.5% of pts. Conclusions: We confirm the activity of lenvatinib in pts with advanced or metastatic T and TC, despite the use of lower doses than the phase 2 study.[Table: see text]

Immunotherapy for Management of Thymic Epithelial Tumors: A Double-Edged Sword.

Simple SummaryImmunotherapy has a rapidly expanding role for the treatment of several cancers due to durable clinical activity and favorable tolerability. However, the unique biology of thymic epithelial tumors (TETs) increases the risk of immune-mediated toxicity. In this paper we review the biology of thymic cancers and its impact on the potential benefits and risks of immunotherapy. We describe the results of completed clinical trials of immune checkpoint inhibitors for advanced TETs and provide an overview of potential biomarkers of response or toxicity of immunotherapy that might influence future development of immunotherapeutic modalities for the treatment of advanced thymoma and thymic carcinoma.Thymic epithelial tumors (TETs) are rare thoracic cancers that are broadly classified as thymomas and thymic carcinomas. Surgery is the cornerstone of management for early-stage disease. There are a limited number of effective treatment options for patients with advanced or recurrent disease. The occurrence of paraneoplastic autoimmune disorders in patients with TETs, especially thymomas, creates significant challenges for the development of immunotherapy, including immune checkpoint inhibitors, as a feasible treatment option. In addition, patients with TETs are at increased risk for the development of immune-mediated toxicity with a predilection for musculoskeletal and neuromuscular adverse events upon treatment with immunotherapy. The identification of biomarkers of response and toxicity is expected to play a key role in harnessing the benefits of immunotherapy for patients with TETs. In this paper we review the biology of TETs and the potential effects on the tolerability of immunotherapy. The results of clinical trials of immune checkpoint inhibitors for the treatment of advanced TETs are described to understand the potential risks and benefits of immunotherapy. We also provide an overview of future avenues for treatment with novel immunotherapeutic modalities and opportunities to develop biomarkers to improve the safety and tolerability of immunomodulatory treatments in patients with TETs.

An Overview of Surgical Treatment of Thymic Epithelial Tumors in Korea: A Retrospective Multicenter Analysis.

BackgroundThymic epithelial tumors (TETs) are rare, and information regarding their surgical outcomes and prognostic factors has rapidly changed in the past few decades. We analyzed surgical treatment practices for TETs and outcomes in terms of overall survival (OS) and freedom from recurrence (FFR) during a 13-year period in Korea.MethodsIn total, 1,298 patients with surgically resected TETs between 2000 and 2013 were enrolled retrospectively. OS and FFR were calculated using the Kaplan-Meier method and evaluated with the log-rank test. Prognostic factors for OS and FFR were analyzed with multivariable Cox regression.ResultsA total of 1,098 patients were diagnosed with thymoma, and 200 patients were diagnosed with thymic carcinoma. Over the study period, the total number of patients with surgically treated TETs and the proportion of patients who underwent minimally invasive thymic surgery (MITS) increased annually. The 5-year and 10-year survival rates of surgically treated TETs were 91.0% and 82.1%, respectively. The 5-year and 10-year recurrence rates were 86.3% and 80.0%, respectively. The outcomes of surgically treated TETs improved over time. Multivariable Cox hazards analysis for OS, age, tumor size, and Masaoka-Koga stage were independent predictors of prognosis. The World Health Organization classification and tumor-node-metastasis (TNM) staging were also related to the prognosis of TETs.ConclusionSurgical treatment of TETs achieved a good prognosis with a recent increase in MITS. The M-K stage was the most important prognostic factor for OS and FFR. The new TNM stage could also be an effective predictor of the outcomes of TETs.

Can the Ratio SUVmax of the Lesion/SUVmax of Mediastinal Tissues Guide the Choice of Surgical Access for the Resection of Thymic Epithelial Tumors?

BackgroundThere are studies showing the utility of the 18-fluorodeoxyglucose positron emission tomography (18FDG PET) scan in the management of patients with thymic epithelial tumors. It seems to be a correlation between the standard uptake value (SUVmax) of thymic epithelial tumors and the histological type and the stage. This study aims to use the ratio of the SUVmax of the lesion to the SUVmax of the adjacent mediastinal tissues in order to guide the choice of the surgical access.MethodsAll patients who presented an anterior mediastinal lesion with a high suspicion of being of thymic origin were included in a prospective database. A ratio inferior to 1 could predict a benign nature and less aggressive behavior, and a minimally invasive approach was performed. A ratio superior to 1 suggested a malignant and aggressive behavior, and a median sternotomy (or a thoracotomy) was performed.ResultsThere were 15 male (mean age 44.6 ± 16.26 years, range 25–73) and 15 female patients (mean age 50.1 ± 16.94 years, range 25–76). When the ratio is inferior to 1, it predicts benign disease in 80% of cases. When it is superior to 1, it predicts in half of cases advanced histological types (high risk thymomas and thymic carcinomas). On the contrary, it can quite accurately predict advanced Masaoka–Koga stages.ConclusionsThe protocol of this study is in accordance with the current literature showing the utility of 18FDG PET scan in the treatment of thymic epithelial tumors. This study goes one step further since the choice of surgical access is based on the SUVmax values. The ratio SUVmax of the lesion/SUVmax of the mediastinal tissues could be a new marker, more pertinent than absolute SUVmax values.

Molecular landscape of thymic epithelial tumors.

Thymic epithelial tumors (TETs) are extremely rare and represent the most frequent tumors of the anterior mediastinum originating from epithelial cells in the thymus. Thymic epithelial tumors include thymomas (TM), thymic carcinomas (TC) and thymic neuroendocrine neoplasms (TNEN). Thymomas are the most predominant and are associated with autoimmune diseases. The available data suggests that the different histological subtypes have specific molecular alterations. Thymic carcinoma shows recurrent gene mutations, but further investigations are needed to understand the role of those mutations in the pathogenetic of the TETs. Some of the new emerging identified molecular alterations have the potential to offer new targeted therapies opening new possibilities for the treatment of thymic epithelial tumors.

The role of immunotherapy for management of advanced thymic epithelial tumors: a narrative review.

The emergence of immunotherapy as a modern pillar of cancer treatment has changed the treatment landscape for various cancers. Immune checkpoint inhibitors directed at programed death-1 (PD-1) or its ligand (PD-L1), in particular, have found widespread clinical applications and have resulted in durable responses and an improvement in survival of patients with advanced or metastatic disease. Tumor cell PD-L1 expression and tumor mutation burden (TMB) are biomarkers of response and efforts are underway to identify other biomarkers that might predict benefit with these drugs. Most patients tolerate immunotherapy well, although a subset of patients develop immune-mediated toxicity due to excessive immune stimulation. Thymic epithelial tumors (TETs) have a unique biology which can predispose to development of autoimmune paraneoplastic disease, especially in patients with thymoma. Due to defects in immunological self-tolerance, the use of immunotherapy in TET patients is associated with an increased risk of immune-mediated adverse events, which can be potentially life-threatening. Development of biomarkers of response and toxicity is particularly important for the treatment of TETs since it is important to identify patients who might benefit from treatment and be at low risk for development of severe immune toxicity. The use of immunotherapy in patients with autoimmune disorders and those who have previously experienced immune-mediated toxicity is currently an area of active research. Various risk mitigation strategies are under evaluation in prospective clinical trials, including trials of immune checkpoint inhibitors in patients with thymic cancers.