ERK5 Activity Prevention Improves the Antitumor Efficacy of Fluvastatin on Thymic Carcinoma.

BACKGROUND/AIM: Thymic carcinoma is a rare cancer type with limited treatment options. Our previous study demonstrated that statins, which inhibit 3-hydroxy-3-methylglutaryl coenzyme A reductase, can prevent thymic carcinoma. However, the mechanisms through which statins affect intracellular events in cancer cells are not well understood. The aim of the study was to determine how thymic carcinoma modulates the intracellular signals in response to statin administration. MATERIALS AND METHODS: We analyzed statin-induced protein phosphorylation in Ty82 human thymic carcinoma cells, which were cultured with fluvastatin, and protein phosphorylation was examined using western blotting. RESULTS: Treating Ty82 with fluvastatin led to ERK5 phosphorylation via protein prenylation attenuation. The antitumor effects of fluvastatin on thymic carcinoma were enhanced when combined with an ERK5 inhibitor. CONCLUSION: Statin therapy in combination with ERK5 inhibition may be a promising therapeutic approach for treating thymic carcinoma.

Successful pembrolizumab treatment for microsatellite instability-high thymoma: A case report.

Microsatellite instability (MSI) is a valuable biomarker for immune checkpoint inhibitors. We report the first case of MSI-high thymoma successfully treated with pembrolizumab. This patient had pleural dissemination and was treated with two cytotoxic chemotherapy regimens including carboplatin and paclitaxel combination therapy and pemetrexed, which did not have the desired effect. Because MSI status was high by using the surgical specimen, pembrolizumab was administered as 3rd line chemotherapy. After three courses, the pleural lesions dramatically shrunk, which confirmed a partial response. Although MSI-high thymoma is rare, our results suggest the necessity to evaluate MSI status in patients with thymoma.

Long-term follow-up and exploratory analysis of lenvatinib in patients with metastatic or recurrent thymic carcinoma: Results from the multicenter, phase 2 REMORA trial.

OBJECTIVES: The main objective of this report was to detail the long-term follow-up data from the REMORA study, which investigated the safety and efficacy of lenvatinib in patients with thymic carcinoma. In addition, an exploratory analysis of the association between relative dose intensity (RDI) and the efficacy of lenvatinib is presented. MATERIALS AND METHODS: The single-arm, open-label, phase 2 REMORA study was conducted at eight Japanese institutions. Forty-two patients received oral lenvatinib 24 mg once daily in 4-week cycles until the occurrence of intolerable adverse events or disease progression. The REMORA long-term follow-up data were evaluated, including overall survival (OS). RDI was calculated by dividing the actual dose administered to the patient by the standard recommended dose. This trial is registered on JMACCT (JMA-IIA00285) and on UMIN-CTR (UMIN000026777). RESULTS: The updated median OS was 28.3 months (95 % confidence interval [CI]: 17.1-34.0 months), and the OS rate at 36 months was 35.7 % (95 % CI: 21.7 %-49.9 %). When grouped by RDI of lenvatinib, the median OS was 38.5 months (95 % CI: 31.2-not estimable) in patients with ≥ 75 % RDI and 17.3 months (95 % CI: 13.4-26.2 months) in patients with < 75 % RDI (hazard ratio 0.46 [95 % CI: 0.22-0.98]; P = 0.0406) at 8 weeks. Patients who maintained their lenvatinib dose over 8 weeks had a higher objective response rate than patients whose doses were reduced (75.0 % vs 29.4 %; P = 0.0379). No new safety concerns or treatment-related deaths were reported, and lenvatinib had a tolerable safety profile. CONCLUSION: This follow-up report updated OS in patients with metastatic or recurrent thymic carcinoma. A higher RDI of lenvatinib at 8 weeks could be associated with improved outcomes.

Chemotherapy versus chemotherapy plus immune checkpoint inhibitors for the first-line treatment of unresectable thymic carcinoma: A multicenter retrospective study.

Thymic carcinoma (TC) is a rare malignant tumor with a poor prognosis, and there is currently limited data on the use of immunotherapy in patients with unresectable TC. In this study, data of patients with unresectable TC diagnosed from January 2017 were retrospectively collected from multiple centers. Treatment response, progression-free survival (PFS), overall survival (OS), survival-independent prognostic factor, and adverse events (AEs) were further analyzed. As a result, a total of 93 patients with unresectable TC were enrolled, of which 54 received first-line chemotherapy, and 39 received chemotherapy plus immune checkpoint inhibitors (ICIs). The objective response rate was 50% (27/54) in the chemotherapy group and 76.9% (30/39) in the chemotherapy plus ICIs group. The chemotherapy plus ICIs group achieved significant median PFS benefit (8.8 vs. 34.9 months, p < .001) and median OS benefit (41.8 months vs. not reached, p = .025). Multivariate analysis showed that ICIs and local therapy were independent prognostic factors for PFS. In addition, 17 patients developed immune-related AEs (IRAEs), of which 15 (38.5%) had Grade 1 or 2 IRAEs and 2 (5.1%) had Grade 3 IRAEs in the chemotherapy plus ICIs group. In conclusion, the efficacy of chemotherapy plus ICIs is superior to chemotherapy, and the adverse effects are manageable in patients with unresectable TC.

Steroid-resistant minimal change nephrotic syndrome associated with thymoma treated effectively with rituximab following thymectomy and cyclosporine: a case report.

BACKGROUND: Minimal change nephrotic syndrome (MCNS) can be complicated by thymoma; however, no standard therapy for thymoma-associated MCNS has yet been established. We herein describe a case of steroid-resistant MCNS associated with thymoma, treated effectively with rituximab. CASE PRESENTATION: A 71-year-old Japanese man was referred to our department with severe proteinuria (20 g/gCr). Renal biopsy showed minimal change disease and computed tomography revealed an anterior mediastinal mass. Based on these findings, he was diagnosed with thymoma-associated MCNS. He was treated with oral prednisolone (50 mg/day) and cyclosporine, and underwent thymectomy and plasma exchange. However, no improvement in proteinuria was observed. He therefore received intravenous rituximab 500 mg, resulting in a marked decrease in proteinuria from 5328 to 336 mg/day after 1 week. CONCLUSIONS: This case suggests that rituximab might be an effective therapy in patients with steroid-resistant MCNS associated with thymoma.

Advanced thymic carcinoma with a hepatic metastasis treated with chemotherapy and staged resection.

Thymic carcinoma is rare, with resulting treatment of patients with extrathoracic metastasis being on a case-by-case basis. We describe the management of a woman in her 70s with an incidentally discovered cystic hepatic lesion with confirmation of a solitary extrathoracic metastasis from a synchronous primary thymic carcinoma. Following chemotherapy and staged resection of the metastasis and the primary tumour, the patient remained free of disease on radiological surveillance 6 months postoperatively.

Artemis: A Multicenter, Open-Label, Single-Arm, Phase II Study to Evaluate the Efficacy and Safety of First-Line Carboplatin/Paclitaxel/Lenvatinib/Pembrolizumab Combination for Previously Untreated Advanced or Recurrent Thymic Carcinomas.

BACKGROUND: Thymic carcinoma is a rare cancer with an aggressive clinical presentation and no organotypic symptoms. Despite using platinum-based chemotherapy as first-line treatment, the prognosis remains poor, necessitating a novel therapeutic strategy. METHODS: The artemis trial is a Phase II, single-arm, multicenter study designed to evaluate the efficacy and safety of carboplatin, paclitaxel, lenvatinib, and pembrolizumab as first-line chemotherapy for patients with advanced or recurrent thymic carcinoma. A total of 35 patients will be enrolled in this study and will receive induction therapy every 3 weeks for up to 4 cycles, followed by pembrolizumab every 3 weeks, and daily lenvatinib as maintenance therapy for up to 31 cycles (for 2 years). Lenvatinib will be continued until disease progression or unacceptable toxicity based on the discretion of the attending physician. CONCLUSION: The primary endpoint of the study is the objective response rate, with secondary endpoints including progression-free survival, overall survival, duration of response, disease control rate, and safety profile. TRIAL REGISTRATION: ClinicalTrials.gov NCT05832827 Registered on April 27, 2023, https://classic. CLINICALTRIALS: gov/ct2/show/NCT05832827. Japan Registry of Clinical Trials (jRCT), jRCT2031230114. Registered on May 22, 2023, https://jrct.niph.go.jp/latest-detail/jRCT2031230114.

Dexamethasone improves thymoma-associated myasthenia gravis via the AKT-mTOR pathway.

Clinically, thymoma patients are often complicated with myasthenia gravis (MG). Dexamethasone, a glucocorticoid with anti-inflammatory effects, could be used as an immunosuppressant for thymoma-associated MG, but the mechanism of action remains to be explored. In this study, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, weighted gene co-expression network analysis (WGCNA) of potential targets was performed by screening the intersection targets of dexamethasone and thymoma-associated MG from the database. Furthermore, the key targets and core active components were identified by topological analysis of the protein-protein interaction (PPI) network. Molecular docking technology was applied to screen the complexes with stable binding of dexamethasone and core targets. Patients with thymoma were divided into two groups according to whether they received dexamethasone before operation, and immunohistochemistry and western blot were used to verify the selected target of dexamethasone in treating thymoma-associated MG. The results showed that the action pathway of dexamethasone on the disease was closely enriched to phosphatidylinositol 3-kinase (PI3K)-protein kinase B (PKB/AKT), mammalian target of rapamycin (mTOR) signaling pathways. The expressions of AKT1 and its downstream molecule mTOR in the thymoma microenvironment of thymoma-associated MG patients who did not receive dexamethasone before operation were higher than those in the group receiving dexamethasone before operation. This study demonstrates that dexamethasone can promote apoptosis through the AKT-mTOR pathway for the treatment of thymoma-associated MG, as validated by network pharmacology predictions and clinical specimen experiments, and can be verified by large-scale clinical trials in the future. This study also provides theoretical support and new research perspectives for this disease.

Characteristics and outcome of systemic treatment for metastatic or unresectable thymic carcinoma: A single institution experience.

BACKGROUND: Thymic carcinoma is a rare disease with an incidence of around 0.5 cases per million with a poor prognosis. The aim of this study was to assess patient outcomes with advanced thymic carcinoma receiving first-line chemotherapy. METHODS: In our retrospective cohort study, we included patients who underwent treatment for metastatic thymic carcinoma between January 2013 to December 2019 in our hospital. Overall survival, progression-free survival (PFS), objective response rates (ORR) and chemotherapy regimens were assessed and analyzed. RESULTS: A total of 27 patients were retrospectively analyzed. All patients received a platinum (cisplatin or carboplatin) based regimen as first-line chemotherapy (29.6% received ADOC, 11.1% received PE, 40.7% received CP, 14.8% received CAP). The median PFS on first-line chemotherapy was 199 days. The response rate was 40.7%. Median overall survival (OS) was 585 days. Positive CD5 staining was associated with better PFS. CONCLUSION: We highlight the critical role of platinum-based chemotherapy agents as a primary treatment modality in advanced thymic carcinoma, underscoring the efficacy of platinum as a first-line option for recurrent disease, even in cases previously treated with platinum. Additionally, our findings indicate that CD5 positivity could be associated with improved PFS, suggesting its potential as a prognostic marker.

GOOD SYNDROME: CYTOMEGALOVIRUS RETINITIS CASE CHALLENGE.

PURPOSE: To describe cytomegalovirus retinitis in a patient with Good syndrome (hypogammaglobulinemia and thymoma), ocular progression despite treatment and fatal outcome. METHODS: A 71-year-old woman with unilateral panuveitis of unknown cause and a history of thymoma resection was referred to the clinic. Visual acuity was 20/100 in her right eye and light perception in her left eye. In slit-lamp examination, the right eye had inferior, fine, pigmented keratic precipitates, 2+ anterior chamber cells, cataract, and 2+ vitreous cells, with no fundus detail and normal ocular ultrasound results. Left eye presented a white cataract, chronic hypotony, and increased choroidal thickness with calcifications. Laboratory evaluations showed normal or negative results for common causes of infection and inflammation. Prednisolone acetate eye drops were started, with improvement of AC inflammation. Cataract surgery was performed, reaching visual acuity of 20/30. Two years later, visual acuity had decreased and 2+ vitritis and retinitis were found. On clinical suspicion of masquerade syndrome, a vitrectomy biopsy was performed; pathologic assessments reported no data on ocular lymphoma. Leukopenia and lymphopenia were found: immunoglobulin levels, CD4 count, and viral load revealed systemic immunosuppression. The aqueous tap was positive for cytomegalovirus. Oral valganciclovir and intravitreal ganciclovir were initiated. RESULTS: In a patient with previous resection of thymoma and hypogammaglobulinemia, final diagnosis was Good syndrome, with cytomegalovirus retinitis being secondary to immunosuppression. Despite treatment, cytomegalovirus retinitis progressed and systemic deterioration resulted in mortal outcome. CONCLUSION: Good syndrome is an extremely rare disease, and association with cytomegalovirus retinitis is uncommon. To the authors' knowledge, only 14 cases exist in the literature.

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.

A late relapse thymoma and pure red cell aplasia case with an over 5 years of clinical response under everolimus.

Although several agents showed some clinical activity in patients with recurrent thymoma, there is no standard treatment option. Here, we report a late relapse thymoma and pure red cell aplasia case, responsive to everolimus with over 5 years of clinical benefit following multiple lines of treatment. Everolimus controlled the rapidly progressive disease in our patient without significant toxicity.

Locally advanced thymoma; does neoadjuvant chemotherapy make a difference?

BACKGROUND: Regardless of its rare occurrence, Thymoma remains the most frequently encountered primary tumor of the anterior mediastinum comprising about 50% of all masses in the region. Surgical resection, via thymectomy, remains the mainstay treatment modality. In locally advanced and borderline resectable tumors, neoadjuvant chemotherapy (NACT) may be utilized to increase the chance of R0 resection, raising the question of its efficacy and safety. METHODS: Demographic and clinical data from patients who presented to a tertiary cancer center between January 2015-October 2021 with a diagnosis of thymoma and underwent curative surgical resection was collected. Computed tomography scan was used to delineate clinical staging, tumor size and to detect post-therapeutic variations in tumor burden. The response evaluation criteria in solid tumors (RECIST) was used to classify the effect of NACT on tumor burden. The pathological response was determined by measuring the percentage of necrotic tissue. RESULTS: A total of 23 patients were diagnosed with thymoma. Most patients were male with a mean age 46 (± 15) years at diagnosis. The most common clinical stage was stage II with 5 patients (22%). A total of 12 patients had NACT as compared to 11 patients who had upfront surgery. The mean change in tumor volume was 165 cm3 (p = 0.079) and the change in and maximum diameter was 1.53 ± 1.49 cm (p < 0.01). The effect of NACT on tumor burden based on RECIST criteria was minimal as 8 patients had stable disease. Based on pathological findings, the average necrotic portion of the tumor was 39.5% (p = 0.152). The overall survival rate is 95.65%, mean survival was 115 months (4-125). Recurrence occurred in 5 patients. The NACT group had a higher risk for recurrence (4; 33.3%) with a mean survival of 43.8 months compared to 59.6 months in those who did not receive induction therapy. CONCLUSIONS: The exact role of induction chemotherapy in locally advanced thymoma patients remains controversial. NACT effect after utilizing radiological and pathological assessment tools was not found to significantly improve oncological outcomes compared to upfront surgery in locally advanced disease, with minimal radiologic and pathologic effect. To further demonstrate the impact of induction chemotherapy, we recommend multicentric collaborative studies.

Thymoma with pleural metastases. / Tymom med pleurametastaser.

Metastatic thymoma is a rare and serious condition that is treated with cytostatics according to the guidelines. Cytostatics have limited efficacy and are toxic. This case report illustrates how glucocorticoid treatment can have a significant effect.

Efficacy and safety of nivolumab for patients with pre-treated type B3 thymoma and thymic carcinoma: results from the EORTC-ETOP NIVOTHYM phase II trial.

BACKGROUND: Thymic malignancies are rare intrathoracic tumors, which may be aggressive and difficult to treat. They represent a therapeutic challenge in the advanced/metastatic setting, with limited treatment options after the failure of first-line platinum-based chemotherapy. They are frequently associated with autoimmune disorders that also impact oncological management. MATERIALS AND METHODS: NIVOTHYM is an international, multicenter, phase II, two-cohort, single-arm trial evaluating the activity and safety of nivolumab [240 mg intravenously (i.v.) q2 weeks] alone or with ipilimumab (1 mg /kg i.v. q6 weeks) in patients with advanced/relapsed type B3 thymoma or thymic carcinoma, after exposure to platinum-based chemotherapy. The primary endpoint is progression-free survival rate at 6 months (PFSR-6) based on RECIST 1.1 as per independent radiological review. RESULTS: From April 2018 to February 2020, 55 patients were enrolled in 15 centers from 5 countries. Ten patients (18%) had type B3 thymoma and 43 (78%) had thymic carcinoma. The majority were male (64%), and the median age was 58 years. Among the 49 eligible patients who started treatment, PFSR-6 by central review was 35% [95% confidence interval (CI) 22% to 50%]. The overall response rate and disease control rate were 12% (95% CI 5% to 25%) and 63% (95% CI 48% to 77%), respectively. Using the Kaplan-Meier method, median progression-free survival and overall survival by local assessment were 6.0 (95% CI 3.1-10.4) months and 21.3 (95% CI 11.6-not estimable) months, respectively. In the safety population of 54 patients, adverse events (AEs) of grade 1/2 were observed in 22 (41%) patients and grade 3/4 in 31 (57%) patients. Treatment-related AEs of grade 4 included one case of neutropenia, one case of immune-mediated transaminitis, and two cases of myocarditis. CONCLUSIONS: Nivolumab monotherapy demonstrated an acceptable safety profile and objective activity, although it has been insufficient to meet its primary objective. The second cohort of NIVOTHYM is currently ongoing to assess the combination of nivolumab plus ipilimumab.

Study Design and Rationale for Marble Study: A Phase II Trial of Atezolizumab (MPDL3280A) Plus Carboplatin and Paclitaxel in Patients With Advanced or Recurrent Thymic Carcinoma (JTD2101).

BACKGROUND: Thymic carcinoma (TC) is a rare thymic epithelial tumor, and advanced or recurrent TC has limited prognosis. Treatment for chemotherapy-naïve, advanced, or recurrent TC remains unchanged with the combination of carboplatin and paclitaxel; therefore, a new treatment strategy is warranted. Immune checkpoint blockades inhibiting the programmed cell death-1 (PD-1) pathway (PD-1 and its ligand, PD-L1) have shown potential as a monotherapy for TC, although the efficacy of monotherapy was moderate for previously treated TC. We hypothesized that the combination of an anti-PD-L1 antibody, atezolizumab, with carboplatin and paclitaxel, would be effective in inducing immunogenic cell death in patients with advanced or recurrent TC. METHODS: We initiated a multicenter, single-arm, open-label phase II study of atezolizumab combined with carboplatin and paclitaxel for metastatic or recurrent TC. Eligible patients will receive atezolizumab plus carboplatin and paclitaxel every 3 weeks for up to 6 cycles, followed by atezolizumab every 3 weeks for up to 2 years until progression or unacceptable toxicity. A total of 47 patients will be enrolled in this study, with a 24-month enrollment period and 12-month follow-up. The primary endpoint is the objective response rate (ORR), based on an independent central review. The secondary endpoints are the investigator-assessed ORR, disease control rate, progression-free survival, duration of response, overall survival, and safety. RESULTS: This study aims to establish the safety and efficacy of atezolizumab combined with carboplatin and paclitaxel in patients with advanced or recurrent TC. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCT), jRCT2031220144. Registered on June 18, 2022, https://jrct.niph.go.jp/en-latest-detail/jRCT2031220144.

Immune checkpoint inhibitor sintilimab-induced lethal myocarditis overlapping with myasthenia gravis in thymoma patient: A case report.

RATIONALE: Immune checkpoint inhibitors have been extensively used and significantly improved the clinical outcomes in multiple types of cancer. But the immune-related adverse events occur frequently, particularly in thymoma. The cardiac immune-related adverse, which is relatively rare but fatal, have been increasing reported. PATIENT CONCERNS: A 45-year-old thymoma patient was admitted to our hospital after receiving anti-programmed cell death-1 treatment with sintilimab 14 days later, accompanied by abdominal pain, intermittent chest tightness and dizziness. DIAGNOSES: The laboratory tests revealed elevated serum troponin I. Electrocardiogram reported the prolongation of QTc interval. Echocardiography showed small amount of pericardial effusion, a left ventricular ejection fraction of 71%. Coronary artery computed tomography angiography revealed localized noncalcified plaque in the middle of the left anterior descending artery and mild stenosis of the lumen. Enhanced computed tomography scanning of the whole abdomen showed no abnormal signs in the parenchyma organs. Combining the results of the examinations, the Immune checkpoint inhibitor induced myocarditis was diagnosed. INTERVENTIONS: The patient was treated with glucocorticoids (120 mg/day, IV, methylprednisolone) within 24 hours of admission. Seven days later, the patient experienced tachy ventricular arrhythmia and cardiogenic shock and was transferred to intensive care unit after electrical cardioversion, tracheal intubation and cardiopulmonary resuscitation. Intravenous immunoglobulin therapy at 25 g/day was given and methylprednisolone was reduced to 40 mg/day for the next 3 days. Intravenous esmolol and lidocaine were used for correcting arrhythmias. Ventilator positive pressure ventilation was used for respiratory support. She was administrated with plasmapheresis when the electrocardiogram monitoring showed ventricular arrhythmia storms. OUTCOME: The patient progressed to ventricular arrhythmia storms and cardiac failure, which eventually resulted in death. LESSONS: The case aims to raise awareness of immune-mediated cardiotoxicity and bring thoughts to the prospects of immunotherapy in thymoma.

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.