Thymic Carcinoma Patients Research Articles

Expression of excision repair cross-complementation group 1 and class III β-tubulin in thymic carcinoma.

Thymic carcinoma is a rare mediastinum malignant tumor derived from thymic epithelial cells. With the exception of complete resection, an effective therapy has not been established to date for advanced or relapsed thymic carcinoma. The present study examined the protein expression of excision repair cross-complementation group 1 (ERCC1) and class III β-tubulin (TUBB3), which are consider to be indicators of the anticancer activity of platinum-based and taxane-based chemotherapy, respectively. The expression of ERCC1 and TUBB3 proteins was examined in 40 thymic carcinoma patients who underwent either surgical resection or core-needle biopsy. The present study investigated whether the expression of ERCC1 and TUBB3 proteins was associated with the overall survival and clinicopathological factors of thymic carcinoma patients. The expression of ERCC1 and TUBB3 proteins was also evaluated in 50 patients who underwent curative resection for non-small cell lung cancer (NSCLC). The expression of ERCC1 and TUBB3 proteins was positive in 8 cases (20%) among the thymic carcinoma patients. ERCC1 was expressed in 21 cases (42%), while TUBB3 was expressed in 27 cases (54%), among the 50 NSCLC patients evaluated in the present study. Only complete resection was observed to be associated with a better prognosis than incomplete resection (P=0.0341). Other clinicopathological factors, including expression of ERCC1 and TUBB3 proteins, exhibited no effect on overall survival. The expression of ERCC1 and TUBB3 proteins in the thymic carcinoma cases was lower than that in the NSCLC cases. The present results suggest a possibility for better antitumor effects of platinum-based and taxane-based chemotherapy on thymic carcinoma patients.

OA18.03 Safety and Clinical Activity of Avelumab (MSB0010718C; Anti-PD-L1) in Patients with Advanced Thymic Epithelial Tumors (TETs)

Avelumab (MSB0010718C) is a fully human, IgG1 anti-PD-L1 antibody under clinical development. We report safety and clinical activity in patients with relapsed TETs enrolled in a phase I trial (NCT01772004). Patients previously treated with one or more standard therapies, no prior immune checkpoint inhibitors, and with no history of autoimmune disease were eligible. Treatment consisted of avelumab at doses of 10-20 mg/kg iv q2 weeks until disease progression or toxicity. Responses were assessed q6 weeks by RECIST 1.1. Correlative studies included evaluation of tumor cell PD-L1 expression and peripheral blood immune subset analysis. 7 patients with thymoma and 1 with thymic carcinoma (TC) were treated with avelumab; 3 patients with thymoma (2 B3, 1 B2/B3) received avelumab 20 mg/kg; 4 patients with thymoma (1 B1, 3 B2) and 1 TC received 10 mg/kg. Two (29%) patients with thymoma had a confirmed partial response (PR;1 at 20 mg/kg, and 1 at 10 mg/kg), 2 (29%) had unconfirmed PRs, 2 (29%) stable disease (SD) and 1 (14%) progressive disease; the TC patient had SD. Most adverse events (AEs) were mild (grade 1 or 2). Grade 3 and 4 AEs were observed in 3 (38%) patients each, and included potential immune-related AEs (irAEs) in 5 cases. irAEs resolved completely with oral steroids in 3 patients, and incompletely in 1 patient. One patient required cyclosporine A for treatment of irAEs. All 4 responders experienced irAEs (myositis in 3 patients, all after 1 dose of avelumab, and enteritis in 1 patient). Pre- and post-treatment tumor biopsies were available for analysis of PD-L1 expression and intratumoral immune infiltrates from three patients treated at 20 mg/kg. In one case the post-treatment biopsy showed necrotic tissue with no viable tumor. In the other two cases diffuse, membranous PD-L1 staining of epithelial cells was seen in both pre- and post-treatment biopsies. The immune infiltrate consisted of immature T cells in pre-treatment tumor samples in both cases. The post-treatment biopsy showed continued presence of immature T cells in one case and a mature CD8+ T cell phenotype in the other case. Decreased CTLA4+ regulatory T cells and decreased ratio of granulocytic vs. monocytic myeloid-derived suppressor cells was seen post-treatment at the 20mg/kg dose. Avelumab is active in patients with recurrent thymoma. Strategies need to be developed to reduce the risk of development of irAEs in response to immune checkpoint inhibitor therapy in patients with thymoma.

P2.04-019 A Peripheral Immune Signature Associated with Clinical Activity of Sunitinib in Thymic Carcinoma: Topic: Thymic Malignancies Clinical and Translational

We have previously reported an objective response rate of 26% and disease stabilization in 65% of patients with advanced thymic carcinoma (TC) treated with the multi kinase inhibitor sunitinib after failure of platinum-based chemotherapy. The current study investigates the impact of sunitinib on systemic immunity in patients with thymic epithelial tumors with an aim to discover blood-based, predictive immune biomarkers. Patients with thymoma and TC received sunitinib at a dose of 50 mg once daily in 6-week cycles consisting of 4 weeks of treatment followed by 2 weeks without treatment. Results from 15 patients with TC are reported here. Blood samples were collected before initiation of sunitinib therapy (Cycle 1 day 1; C1D1), and prior to treatment on day 1 of cycles 2 and 3 (C2D1; C3D1). Multiparameter flow cytometry was used to study T-cell subsets with immune checkpoint expression, four phenotypes of myeloid-derived suppressor cells (MDSCs) with CD40, and CD14+ monocytes with HLA-DR expression. Expression of 730 immune-related genes in peripheral blood was analyzed by NanoString technology. Differences in paired markers or changes in markers between two time points was evaluated by the Wilcoxon signed rank test. The Kaplan-Meier method was used to obtain estimates of progression-free survival (PFS) and overall survival (OS). Immunosuppressive Tim-3-positive Tregs declined after 2 cycles of sunitinib (p=0.024). A decrease in granulocytic MDSCs (p=0.012), lineage negative (CD3-CD19-CD56-) MDSCs (p=0.013), and immature MDSCs (p=0.01) but not monocytic MDSCs was observed after 1 cycle of sunitinib. TC patients with no objective response to sunitinib had a higher baseline immature MDSC level than responders (p=0.0044). Greater than median declines in granulocytic MDSC CD40 (C2D1 p=0.027, C3D1 p=0.0046) and lineage-MDSC CD40 (C3D1, p=0.0046) after sunitinib therapy was associated with improved PFS. Similarly, a greater than median decline in CD14+HLA-DRlo/neg monocyte levels on C2D1 was associated with longer PFS (p=0.020). Among the immune genes examined, higher baseline FEZ1 expression was associated with improved PFS and OS. Our findings suggest significant interplay between sunitinib and systemic immunity impacts therapeutic outcome in TC. Monitoring CD40 expression on specific MDSC phenotypes and FEZ1 gene expression may predict a survival benefit after treatment with sunitinib. These results, if validated in larger studies, can serve as potential blood-based predictive biomarkers in TC patients treated with sunitinib.

Mutation analysis of the EGFR gene and its downstream signaling pathway in thymic carcinoma patients from a Chinese Han population.

For thymic carcinoma (TC), which is a rare epithelial neoplasm of the thymus gland, median survival with current treatments is only 2 years. Mutations in the epidermal growth factor receptor (EGFR) gene or its downstream effectors may cause constitutive activation that leads to cell proliferation and metastases. Thus, molecular profiling is essential for selecting TC patients who may respond to anti-EGFR therapies. Genomic DNA was extracted from 61 histological samples of TCs. Real-time polymerase chain reaction (PCR) and direct sequencing were used to assess the mutations in the EGFR downstream pathway. Gene mutations were identified in seven patients (11.5%). In particular, the identified mutations included four mutations in the KRAS gene, one mutation in the BRAF gene, one mutation in the PIK3CA gene, and only one mutation in the EGFR gene itself. Gene mutations in the EGFR downstream pathway were associated with shorter survival time and were observed to be an independent prognostic factor for TC patients. Mutations in the EGFR downstream pathway are not rare in TCs. These data offer interesting possibilities for the future management of TCs, particularly in the era of new targeted therapies.

Prognostic Value of Programmed Death Ligand 1 and Programmed Death 1 Expression in Thymic Carcinoma

The immune checkpoint of the programmed death 1/programmed death ligand 1 (PD-1/PD-L1) pathway is believed to play an important role in evasion of host antitumor immune surveillance in various malignancies; however, little is known about its role in thymic carcinoma. This study investigated PD-1/PD-L1 expression and its association with clinicopathologic features, the expression of immune-related proteins in tumor-infiltrating lymphocytes (TIL), and patient prognosis. PD-L1 and PD-1 expression was evaluated by IHC in 25 thymic carcinoma tissue specimens. Copy number alterations of the PD-L1 gene in 11 cases were assessed in formalin-fixed, paraffin-embedded material using qRT-PCR. Compared with normal subjects, 3 thymic carcinoma patients showed an increase in PD-L1 copy number, whereas 8 did not. PD-L1 was significantly overexpressed in cases with copy number gain as compared with normal cases. High PD-L1 expression was associated with higher disease-free and overall survival rates as compared to cases with low expression. Prognostic analysis revealed low PD-L1 expression and high number of PD-1(+) TILs as significant predictors of poor survival, together with Masaoka-Koga stage IVa/IVb disease and incomplete resection. In the quantitative analysis of TILs, PD-L1 expression correlated proportionally with the number of infiltrating CTLs. Here, for the first time, we report that PD-L1 and PD-1 expression might be useful prognostic predictors in thymic carcinoma. Further studies are expected to substantiate the prognostic value of PD-L1 and PD-1 expression, and the potential efficacy of targeting the PD-1/PD-L1 pathway in thymic carcinoma via immunotherapy. Clin Cancer Res; 22(18); 4727-34. ©2016 AACR.

Prognostic value of preoperative serum lactate dehydrogenase in thymic carcinoma.

The prognostic value of serum lactate dehydrogenase (LDH) has been demonstrated in various solid tumors. We attempted to determine whether serum LDH was predictive of survival in thymic carcinoma after surgical resection. Ninety-five patients with thymic carcinoma treated in our hospital between January 2005 and December 2015 were retrospectively enrolled. Serum LDH was measured before surgery and categorized as low or high relative to the upper limit of normal (ULN) (225 U/L). The relationships of serum LDH level and other clinical variables with survival were estimated by Cox regression and Kaplan-Meier survival analysis. Serum LDH levels were found to be significantly associated with overall survival (OS) and progression-free survival (PFS) of these patients. The 1-, 3-, and 5-year PFS were 76%, 51%, and 38%, and the 1-, 3- and 5-year OS were 97%, 75%, and 46%, respectively. Univariate analysis found that high serum LDH (>225 U/L) was associated with both lower OS [hazard ratio (HR) =2.710; 95% confidence interval (CI): 1.363-1.5.391; P=0.004] and PFS (HR =3.365; 95% CI: 1.776-6.374; P<0.001). Multivariate analysis found that high serum LDH was associated with lower PFS (HR =2.122; 95% CI: 1.056-4.267; P=0.035). Moreover, high LDH was significantly associated with advanced Masaoka stage (P=0.001). High serum LDH (>225 U/L) was an independent predictor of decreased PFS in thymic carcinoma patients. It was also significantly associated with reduced OS, but was not an independent predictor of death in those patients.

Prognostic value of preoperative neutrophil-lymphocyte ratio is superior to platelet-lymphocyte ratio for survival in patients who underwent complete resection of thymic carcinoma.

Preoperative neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) have prognostic value in patients with various operable tumors. The aim of our study was to determine whether NLR and PLR are predictive of survival in thymic carcinoma patients after complete resection. A total of seventy-nine patients who underwent complete resection of thymic carcinoma at our hospital between January 2005 and December 2015 were retrospectively enrolled. Differential leukocyte counts were collected before surgery, and the relationships of NLR, PLR, and other patient clinical variables with survival were estimated by Cox regression analysis and Kaplan-Meier survival analysis. Univariate analysis found that a high level of NLR was associated with lower disease-free survival (DFS) (HR: 3.385, 95% CI: 1.073-10.678, P=0.037) and lower overall survival (OS) (HR: 12.836, 95% CI: 1.615-101.990, P=0.016). The optimal NLR threshold of 4.1 could stratify the patients with high risk of recurrence or metastasis (P=0.026) and death (P=0.006). Meanwhile, the NLR value of >4.1 in those patients was associated with bigger tumor size (P=0.035) and more advanced Masaoka stages (P=0.040) compared with NLR ≤4.1. However, the PLR and other variables were not significantly associated with survival in thymic carcinoma patients. The preoperative NLR of >4.1 was significantly associated with larger tumor size, more advanced Masaoka stages and reduced DFS and OS, but was not an independent predictor of survival in thymic carcinoma patients after complete resection.

Sunitinib in patients with advanced thymic malignancies: Cohort from the French RYTHMIC network

BackgroundSunitinib is a potent oral tyrosine kinase inhibitor of VEGFRs, KIT, and PDGFRs. In a single arm phase II trial, sunitinib has demonstrated its potential activity in refractory thymic carcinoma (TC) and thymoma (T). Taking advantage of the French RYTHMIC network prospective database, we investigated the off-label efficacy of sunitinib in previously-treated thymic epithelial tumors (TETs) patients not included in a clinical trial. MethodsRYTHMIC database started in 2012, and prospectively collects clinical, imaging, treatment, and follow-up data of all patients diagnosed with TET, for whom management is discussed at a national multidisciplinary tumor board. All patients who received sunitinib were selected for this analysis. Results28 patients from 7 institutions were identified, including 20 TC and 8T; 32% of patients were females, and median age was 50 years. Fifteen patients (54%) received sunitinib as ≥4th line treatment. The initial daily dose of sunitinib was 50mg in 11 patients, 37.5mg in 16 patients and 25mg in 1 patient. Sunitinib adverse events were all manageable and tolerable; 8 patients had to stop sunitinib due to toxicity after a median duration of treatment of 2.7 months. In the overall population, disease control rate was of 63% (86% for T, and 55% for TC); overall response rate was 22% (29% for T, and 20% for TC). Median PFS in the whole population was 3.7 months (5.4 months for T, and 3.3 months for TC, p=0.097). The median overall survival in the whole population was 15.4 months: survival was not reached for T, and was 12.3 months for TC patients (p=0.043). ConclusionSunitinib is an active treatment in TETs irrespective of histological subtype, supporting the use of tyrosine kinase inhibitors with anti-angiogenic activity as alternative treatment options in refractory disease.

Clinicopathological analysis of 241 thymic epithelial tumors-experience in the Shanghai Chest Hospital from 1997-2004.

To assess the correlation of WHO histological classification of thymomas and thymic carcinomas (TCs) with prognosis in recently treated patient cohort compared to a historical one from a single institution. Retrospective review of clinical charts and histological sections of 241 patients treated during 1997-2004. Univariate and multivariate analysis of associations between risk factors including gender, age, tumor size, myasthenia gravis, WHO histological subtype, Masaoka stage, resection status, (neo-)adjuvant therapies, and survival. The 5-year overall survival (OS) of A, AB, B1, B2, B3 thymomas and TCs patients was 100%, 100%, 94%, 80%, 94% and 45%. Five-year progression-free survival (PFS) was 100%, 96%, 78%, 80%, 78% and 39%, respectively. The 5-year OS of patients with Masaoka stage I, II, III and IV thymomas and TCs was 96%, 89%, 59% and 50%. (Neo-)adjuvant therapies were administered more often than in the historical cohort. Tumor-related death mainly occurred in patients with stage III, IV and B2, B3 thymomas and TCs. By univariate analysis, gender, tumor size, myasthenia gravis (MG) status, histotype, Masaoka stage, resection status and treatment were associated with OS. By multivariate analysis, histological subtype, Masaoka stage, and (neo-)adjuvant therapy were revealed as independent prognostic indicators. WHO histological subtype, Masaoka stage and (neo-)adjuvant treatment have remained independent determinants of OS in patients with thymomas and TCs. Compared with the historical cohort during 1969-1996, prognosis of patients with B2, B3 thymomas has improved, which may be partly due to the increased use of adjuvant therapies. Prognosis of patients with TCs remained unsatisfactory, suggesting that neoadjuvant treatment should be tested to improve survival.

Report of ITMIG 2015 Meeting.

Background: Limited treatment options exist for patients with thymic malignancies (TM), and chemotherapy efficacy is often restricted by cumulative toxicity such as neuropathy (taxanes) and cardiomyopathy (anthracyclines). Single agent amrubicin, a third generation anthracycline and topoisomerase II inhibitor with minimal cardiac toxicity, was investigated in TM patients in this trial. Methods: This was an open-label single drug trial at two institutions in the United States (Stanford University and Indiana University). Eligible patients had TM [thymoma (T) or thymic carcinoma (TC)] with progression or relapse after at least one prior chemotherapy regimen, and adequate organ function including left ventricular ejection fraction (LVEF) of >50%. The initial treatment plan consisted of amrubicin at 40 mg/m 2 IV days 1–3 repeated in 3-week cycles. Results: From July 2011 to April 2014, a total of 33 patients (14T/19TC) were enrolled. There were 14 women and 19 men; age range of 30–81 years; 9 Asian, 1 African-American, 1 Hispanic and 22 non-Hispanic White patients. A high rate of febrile neutropenia (FN) led to an amended starting dose of 35 mg/m 2 days 1–3 repeated in 3-week cycles. In total, 7 patients experienced FN with 1 related death. Other grade 3/4 related events included: thrombocytopenia (n=2), neutropenia without fever (n=3), hyponatremia (n=2), hypokalemia (n=2), anemia (n=7), lethargy/fatigue (n=7), perirectal abscess (n=2), palmar-plantar erythrodysesthesia (n=3), syncope (n=2), venous embolism (n=2), and 1 patient each with sepsis, oral abscess, mucositis, chest pain, and epigastric pain. Other toxicities were generally mild and well tolerated. No significant changes in LVEF were noted on serial echocardiograms. There were 6 partial responses (4T/2TC), 21 with stable disease, and 4 with progressive disease (PD) or death at or before first assessment for a response rate (RR) of 18% and a disease control rate (DCR) of 88% (29%/11% RR in T vs . TC and 100%/78% DCR in T vs. TC). All but 5 patients received at least 4 cycles, and 15 tolerated >10 cycles, with 38 cycles as the highest number to date. Three patients remain on therapy. Conclusions: Amrubicin, at 35 mg/m 2 IV days 1–3 on a 3-week cycle, shows promise as a single agent in pre-treated patients with T and TC with an 18% RR (29% T/11% TC) and no unexpected toxicity. DCRs of 100% in the T patients and 78% in the TC patients were observed. RR and DCR were higher in the T patients compared to the TC patients. Further exploration of amrubicin as a single drug or in combination is warranted in TM.

Gemcitabine in patients previously treated with platinum-containing chemotherapy for refractory thymic carcinoma: radiographic assessment using the RECIST criteria and the ITMIG recommendations

The key drugs for chemotherapy of thymic carcinoma are gradually being revealed in phase II and conventional retrospective studies. Gemcitabine is regarded as one of these key drugs according to the findings of clinical trials in which it was combined with capecitabine. However, the activity of single-agent gemcitabine concerning refractory thymic carcinoma remains unclear. We conducted a retrospective review of the medical records of refractory thymic carcinoma patients previously treated with platinum-containing chemotherapy between 1980 and 2014. Of all 11 patients in this study, the objective response rate regarding gemcitabine was 36.4% [95% confidence interval (CI) 15.2-64.6] using the RECIST criteria and the response criteria proposed by the ITMIG. The median progression-free survival time was 4.3months (95% CI 0.7-11.0). The survival time from the start of gemcitabine treatment was 28.5months (95% CI 5.5-47.8), and from the start of first-line chemotherapy was 46.5months (95% CI 7.3-47.8). Gemcitabine achieved a moderate response and has the potential to be used as a key drug for thymic carcinoma. Some patients treated with gemcitabine demonstrated prolonged cancer control even in later lines of chemotherapy.

Chemotherapy and prognosis in advanced thymic carcinoma patients

OBJECTIVE:The role of chemotherapy in treating advanced thymic carcinoma is unclear. The purpose of the current study was to investigate the efficacy of chemotherapy and the prognostic factors for patients with advanced thymic carcinoma.METHODS:A retrospective review of the medical records of 86 patients treated with chemotherapy for advanced thymic carcinoma was conducted between 2000 and 2012 at our institution. The clinical characteristics, chemotherapy regimens and prognostic factors were analyzed. Survival curves were plotted using the Kaplan–Meier method and the Cox proportional hazard model was used for multivariate analysis.RESULTS:Of the 86 patients, 56 were male and 30 were female. The median survival time was 24.5 months. For the first-line chemotherapy treatment, the objective response rate was 47.7% and the disease control rate was 80.2%. The median progression-free survival for all patients was 6.5 months for first-line chemotherapy. No significant differences in progression-free survival were observed among the different chemotherapy regimens. Multivariate analyses revealed that the prognostic factors for overall survival included performance status (p=0.043), histology grade (p=0.048), and liver metastasis (p=0.047).CONCLUSION:Our results suggest that there is no difference in efficacy between multiagent and doublet regimens. The prognosis of patients with advanced thymic carcinoma can be predicted based on histological grade, liver metastasis and performance status.

Treatment and survival analyses of completely resected thymic carcinoma patients.

PurposeTo investigate the impact of chemotherapy and/or radiotherapy on disease-free survival (DFS) and overall survival (OS) rates of patients with thymic carcinoma after complete resection.MethodsBetween 2001 and 2013, 54 patients with complete resection of thymic carcinoma in Hangzhou Cancer Hospital were retrospectively reviewed. The Kaplan–Meier method was used to evaluate the survival rates. The Cox proportional hazard model was used for multivariate analysis.ResultsAmong the 54 patients, Masaoka stage I was observed in seven patients, II in 22 patients, and III in 25 patients. Sixteen patients received adjuvant chemotherapy (six with chemotherapy alone and ten with radiotherapy and chemotherapy), 25 patients received adjuvant radiotherapy, and 13 patients did not receive radiotherapy and/or chemotherapy. The 5-year DFS and OS rates for all patients were 63.0% and 73.4%, respectively. Univariate analysis revealed that radiotherapy was significantly associated with DFS and OS (P=0.014 and P=0.029, respectively), while adjuvant chemotherapy was not (P=0.122 and P=0.373, respectively). Multivariate analysis showed that adjuvant radiotherapy increased DFS (P=0.041), but not OS (P=0.051).ConclusionComplete resection followed by adjuvant radiotherapy increased disease-free rates of thymic carcinoma patients.

Thymic carcinoma patients with myasthenia gravis exhibit better prognoses.

Thymic carcinoma is an aggressive mediastinal neoplasm with a poor prognosis, but the factors that contribute to its prognosis are not completely understood. Myasthenia gravis (MG) can coexist with thymic carcinoma with low incidence, but the effect MG has on thymic carcinoma prognosis is unknown. Here, we investigated the prognostic factors of thymic carcinoma and the influence of MG on patients with this disease. Between January 1996 and December 2012, 49 patients were diagnosed with thymic carcinoma and surgically treated at our institution. Clinical data and survival information were recorded and systematically reviewed. Kaplan-Meier survival curves were generated, and independent prognostic factors were identified by Cox's proportional hazard model. Complete resection was achieved in 30 patients (61.2 %), and incomplete resection was performed on the other 19 patients (38.8 %). Six of the 49 patients with thymic carcinoma also presented with MG (12.2 %). Interestingly, these 6 patients exhibited much better prognoses when compared to the other 43 patients. Patients with MG also had significantly smaller tumors (P = 0.045), earlier Masaoka stage (P = 0.048), and higher complete resection rates (P = 0.042). However, multivariate analysis demonstrated that complete resection was the only independent predictor for overall survival (OS) (P < 0.001). The OS of patients with thymic carcinoma depends on complete resection, but patients with MG also demonstrate improved prognoses. MG patients have higher rates of complete surgical resection, which may account for their better prognoses. Patients with MG have unique features that may aid in the clinical management of these patients.

Docetaxel for platinum-refractory advanced thymic carcinoma.

Thymic carcinoma is a rare mediastinal neoplasm. While platinum-based chemotherapy has been reported to be effective for advanced thymic carcinoma in a first-line setting, little information is available regarding the benefits of salvage chemotherapy for platinum-refractory thymic carcinoma. This study assessed the efficacy and safety profiles of docetaxel monotherapy for platinum-refractory thymic carcinoma. A total of 13 thymic carcinoma patients treated with docetaxel monotherapy in a second- or later-line setting between January 2003 and April 2014 were retrospectively reviewed. The median age was 61 years (range, 41-75 years). The overall response rate and disease control rate were 31% [95% confidence interval (CI), 6-56%] and 77% (95% CI, 54-100%), respectively. The median progression-free survival and overall survival after docetaxel monotherapy were 5.5 months (95% CI, 2.3-6.5 months) and 24.0 months (95% CI, 9.4-31.2 months), respectively. The most common Grade ≥3 toxicity was neutropenia (62%). No incidents of febrile neutropenia and no treatment-related deaths were recorded. This retrospective analysis demonstrated that docetaxel was active against platinum-refractory thymic carcinoma with acceptable toxicities. Docetaxel monotherapy might be a promising therapeutic option for patients with platinum-refractory thymic carcinoma.

Establishment and characterization of a novel cell line derived from thymoma with myasthenia gravis patients.

BackgroundThymoma is a cancer with rare incidence, but it is a major malignancy in adult anterior mediastinum, occurring in about 40% of patients with myasthenia gravis. Because of the lack of thymic epithelial tumor cell lines, thymoma has lagged far behind other tumors in cytological studies. It is, therefore, quite necessary to establish a new thymic epithelial tumor cell line from Chinese patients to study the pathogenic mechanism and therapeutic methods.MethodsTwenty-three samples of tumor tissues were collected from thymoma and thymic carcinoma patients for primary culture by tissue explant, suspension cell culture method, and collagenase digestion. We detected the biological characteristics and origin of the cell line after the establishment of a novel thymoma cell line.ResultsA novel cell line, designed as Thy0517, was established from thymoma type AB with myasthenia gravis patients by tissue explant. As an immortalized cell line, it always has a stable growth cycle, and there is no change in characteristics and morphology after culturing for 18 months and passing 160 generations in vitro. The experimental data demonstrate that the cell line exhibits the growth characteristics of tumor cells, the doubling time of 37 hours, with tumorigenicity in vitro and chromosome abnormality. Immunocytochemistry indicated that the cell line positive expression of CK7, CK8/18, CK19, CK-pan, CD24, BCL-2, P63, Vimentin, epithelial membrane antigen and epidermal growth factor receptor, lymphocyte related antigen CD99, and TdT were negatively expressed.ConclusionsThe newly established thymic epithelial tumor cell line from Chinese patients provides a model in the study of thymoma and molecularly targeted therapies.

A multicenter phase II study of carboplatin and paclitaxel for advanced thymic carcinoma: WJOG4207L

Thymic carcinoma (TC) is an exceptionally rare tumor, which has a very poor prognosis differing from thymoma. Till date, there has been no report of any results of clinical trials focusing on TC. The role of non-anthracycline-based chemotherapy has not been elucidated since the previous studies included a relatively small number of TC patients. This single-arm study evaluated carboplatin and paclitaxel (CbP) in chemotherapy-naive patients with advanced TC. The study treatment consisted of carboplatin (area under the curve 6) and paclitaxel (200 mg/m(2)) every 3 weeks for a maximum of six cycles. The primary end point was objective response rate (ORR) by independent review. The secondary end points included overall survival (OS), progression-free survival (PFS), and safety. Based on the SWOG 2-stage design, the planned sample size of 40 patients was determined to reject the ORR of 20% under the expectation of 40% with a power of 0.85 and a type I error of 0.05. Forty patients from 21 centers were enrolled for this study from May 2008 to November 2010. Of the 39 patients evaluable for analysis, 36 were pathologically diagnosed by independent review, and 97% patients were eventually TC. There was 1/13 complete/partial responses with an ORR of 36% (95% confidence interval 21%-53%; P = 0.031). The median PFS was 7.5 (6.2-12.3) months, while OS did not reach the median value. Major adverse event was grade 3-4 neutropenia in 34 patients (87%). There was no treatment-related death. In this largest trial with TC, CbP showed promising efficacy in advanced TC when compared with anthracycline-based chemotherapy, which is the current standard treatment of thymic neoplasm. Our results established that CbP, one of the standard treatments for non-small-cell lung cancer, might be an option as a chemotherapy regimen for TC.

Phase II Study of Amrubicin Combined with Carboplatin for Thymic Carcinoma and Invasive Thymoma: North Japan Lung Cancer Group Study 0803

There has been no standard chemotherapy for advanced or recurrent thymic malignancies including thymic carcinoma (TC) and invasive thymoma (IT), though platinum and anthracycline have been reported as effective agents for the treatment of these diseases. The objective of this study was to evaluate the efficacy and safety of the combination of amrubicin (AMR), a new anthracycline agent, and carboplatin (CBDCA) in patients with advanced thymic malignancies. Patients with histologically confirmed thymic malignancies received AMR (35 mg/m, days 1-3) and CBDCA (area under the curve 4.0, day 1) every 3 weeks. Patients who had received previous chemotherapy were treated with a reduced dose of AMR (30 mg/m). The primary end point was objective response rate (ORR), and secondary endpoints were progression-free survival, overall survival, and toxicity profile. From December 2008 to October 2012, 51 patients (33 TC and 18 IT) were enrolled. The median number of treatment cycles was four in each group. The ORR and progression-free survival were 30% (95% confidence interval, 14-46) and 7.6 months in the TC group, and 17% (95% confidence interval, 0-34) and 7.6 months in the IT group, respectively. The ORR of TC patients without previous chemotherapy (n = 19) was 42%. Although grade 3 or 4 hematological toxicities were common including neutropenia (82%) and febrile neutropenia (22%), these were transient and manageable. Nonhematological toxicities were moderate and no treatment-related death was observed. The combination of AMR with CBDCA was active for TC with acceptable toxicity, although it was not effective for IT. Further investigation of this regimen for advanced TC is warranted.

Response to Cytotoxic Chemotherapy in Patients Previously Treated With Palliative-Intent Chemotherapy for Advanced Thymic Carcinoma

BackgroundClinical efficacy of second- and later-line chemotherapy for patients with thymic carcinoma previously treated with chemotherapy remains uncertain; limited data are available about this carcinoma because of its rarity. The aim of this study was to investigate effective chemotherapy for patients with thymic carcinoma previously treated with chemotherapy using a retrospective analysis of responses and times to event. Patients and MethodsWe conducted a retrospective review of the medical records of 23 advanced thymic carcinoma patients previously treated with palliative-intent chemotherapy between 1980 and 2014 in our institution. Clinical demographic characteristics, agents, response, and time to treatment failure for each treatment line and overall survival were reviewed. Factors expected to be associated with survival rates were analyzed. Differences in survival were assessed using Kaplan–Meier analysis and univariate and multivariate Cox proportional hazards regression analyses. ResultsThe study included 13 men (56.5%) and 10 women (43.5%). The median age at diagnosis was 58.5 years. The most common histological subtypes were squamous cell carcinoma (16 patients [69.6%]), followed by neuroendocrine carcinoma (4 patients [17.4%]). The objective response rates of first-, second-, third-, and fourth-line chemotherapy were 60.9%, 39.1%, 23.1%, and 25.0%, respectively. The median survival time was 18.8 months (95% confidence interval, 7.5-40.9 months). Uni- and multivariate analyses of all assessed variables failed to identify any statistically significant indicators of overall survival. ConclusionPatients with thymic carcinoma previously treated with palliative-intent chemotherapy might respond to second- or later-lines of cytotoxic chemotherapy.

Cyclin-dependent kinase inhibitors, p16 and p27, demonstrate different expression patterns in thymoma and thymic carcinoma.

The role of cell cycle inhibitors in tumorigenesis has been proven in various neoplasms; however, their roles in thymic tumors are still unclear. We examined the expression of cell cycle inhibitors such as those of the Cip/Kip family (p21, p27, and p57) and the INK-4/ARF family (p16 and p14) in thymoma and thymic carcinoma. Samples from 41 thymoma and 14 thymic carcinoma patients, and 34 normal thymic tissue samples were prepared for the study. Immunohistochemical analysis using antibodies to p21, p27, p57, p16, and p14 was carried out, and the positivity for these inhibitors in each group was estimated in terms of their subcellular location and percentage of cells showing positive staining. Nuclear p27 showed a stepwise decrease (p < 0.0001), and the cytoplasmic p27 showed a stepwise increase (p < 0.0001) in expression level with the increase in malignancy. p16 in both the nucleus and cytoplasm showed a stepwise increase (p < 0.0001) in expression level with the increase in malignancy. However, as for p21, p57, and p14, there was almost no nuclear or cytoplasmic expression in each group. Our findings suggest that low nuclear and high cytoplasmic p27 expression levels, and high nuclear and cytoplasmic p16 expression levels may correlate with the increase in thymic malignancy.