Chemotherapy and prognosis in advanced thymic carcinoma patients

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.

Malignant Superior Vena Cava Syndrome: A Scoping Review

Malignant superior vena cava syndrome (SVCS) is a clinical problem that results from the obstruction of blood flow in the superior vena cava by an underlying malignancy. This may occur due to external compression, neoplastic invasion of the vessel wall, or internal obstruction with bland or tumor thrombus. Although symptoms are typically mild, SVCS can cause neurologic, hemodynamic, and respiratory compromise. Classic management options include supportive measures, chemotherapy, radiation therapy, surgery, and endovascular stenting. New targeted therapeutics and techniques have also recently been developed, which may have a role in management. Nevertheless, few evidence-based guidelines exist to guide treatment of malignant SVCS, and these recommendations are typically restricted to individual disease sites. Furthermore, there are no recent systematic literature reviews that address this question. Here, we present a theoretical case to frame this clinical problem and synthesize updated evidence published in the past decade relating to the management of malignant SVCS through a comprehensive literature review.

Surgical, Radiation, and Systemic Treatments of Patients With Thymic Epithelial Tumors: A Systematic Review

INTRODUCTION

Thymic epithelial tumors are rare and are classified as thymoma, thymic carcinoma, and thymic neuroendocrine tumors. The objective of this systematic review was to evaluate the treatment options for patients with thymic epithelial tumors.

METHODS

This systematic review was developed by Ontario Health (Cancer Care Ontario)'s Program in Evidence-Based Care and by the Lung Cancer Disease Site Group. MEDLINE, EMBASE, and the Cochrane Library were searched for studies comparing surgical, radiotherapy, or systemic treatments against any combination of these treatments in patients with thymic epithelial tumors. Meta-analyses were conducted with clinically homogenous studies.

RESULTS

A total of 106 studies were included, mainly from observational studies. There was an overall survival benefit with postoperative radiotherapy for patients with thymic carcinoma (hazard ratio = 0.65, 95% confidence interval: 0.47-0.89) and for patients with thymoma (hazard ratio = 0.70, 95% confidence interval: 0.59-0.82), especially for those with a high risk for mortality. Patients with thymic carcinoma or thymoma had a response to chemotherapy. Selection bias affected the results for studies that evaluated neoadjuvant chemotherapy or minimally invasive surgical techniques. Furthermore, the overall survival benefit found for adjuvant chemotherapy may have been confounded by the administration of postoperative radiotherapy.

CONCLUSIONS

For patients with thymoma or thymic carcinoma, the literature is of low quality and subject to bias. There were overall survival benefits with postoperative radiotherapy. The results of this systematic review were used to inform treatment recommendations in a clinical practice guideline. Future large-scale prospective studies that control for confounders are needed.

Combination carboplatin and nab-paclitaxel as a first-line treatment for advanced thymic carcinoma

Thymic carcinoma is a very rare neoplasm for which no optimal chemotherapeutic regimen has been established to date. Hence, we performed this study to investigate the efficacy and safety of carboplatin plus nanoparticle albumin-bound (nab)-paclitaxel as a first-line regimen for patients with advanced thymic carcinoma. We conducted this multi-institutional retrospective cohort study of patients with advanced thymic carcinoma who had received carboplatin plus nab-paclitaxel as a first-line chemotherapy between August 2013 and December 2021. Twelve patients were included in this study and were subjected to efficacy and safety analysis. Their median age was 62 years (range, 47-74 years), and all had an Eastern Cooperative Oncology Group performance status score of 0 or 1. After a median follow-up time of 19.7 months, the overall response rate was 50%; the median progression-free and overall survival times were 8.8 months and 23.3 months, respectively. Chemotherapy-related peripheral neuropathy was observed in 2 patients (16%; each with grade 1). Other toxicities were manageable, and there were no treatment-related deaths. Carboplatin plus nab-paclitaxel as a first-line chemotherapy regimen showed good efficacy and safety in patients with advanced thymic carcinoma.

Efficacy and safety of treatments for advanced thymic carcinoma after failure of first-line platinum-based chemotherapy: A systematic literature review and meta-analysis

Thymic carcinoma (TC) is a rare cancer and patients failing initial chemotherapy (relapse/refractory) face limited therapeutic options given no approved options or consensus standard of care. This study aimed to identify and summarize clinical outcomes of all regimens evaluated in clinical trials of relapsed or refractory patients. Interventional trials enrolling advanced TC patients who failed first-line chemotherapy and reported outcomes in this group were eligible for inclusion in our systemic literature review (SLR). Between-study heterogeneity was assessed to determine the feasibility of pooling specific studies and treatments. Objective response rate (ORR), overall survival (OS), progression-free survival (PFS), and duration of response (DOR) endpoints were of interest for meta-analysis. Nineteen trials were identified in the SLR. Three trials with one or two TC patients were removed from our assessment to reduce publication bias. Response rates among studies with at least ten TC patients varied from 9 % to 38 %. Pooled ORRs in patients receiving S-1 (46 patients), sunitinib (46 patients), or pembrolizumab (66 patients) were 28 %, 24 %, and 21 %, respectively. Prolonged duration of response with pembrolizumab was observed with a pooled median of 23.8 months (95 % confidence interval [CI]: 12, not reached). Median PFS of five months or greater was reported in patients treated with sunitinib, lenvatinib, pembrolizumab, capecitabine + gemcitabine, everolimus, or S-1. Median OS of 20 months or greater was reported in trials evaluating S-1 or pembrolizumab; this endpoint was not reached in trials evaluating lenvatinib, regorafenib, or sunitinib. Generalizability of treatment effects is challenging in the research of rare diseases and meta-analysis of clinical outcomes may help to increase precision and relevance of results to the larger TC population. Our study found limited treatment options upon relapse, demonstrating a need for further investigations into novel therapeutics and well-powered clinical trials to better inform on optimal treatments.

The Studies of Prognostic Factors and the Genetic Polymorphism of Methylenetetrahydrofolate Reductase C667T in Thymic Epithelial Tumors

Objective

To describe the clinical features of a cohort of patients with thymic epithelial tumors (TETs) and to analyze their prognostic factors. In particular, we investigated the correlation between the genetic polymorphism of methylenetetrahydrofolate reductase (MTHFR) C667T and the incidence of TETs.

Methods

Pathological records were reviewed from the database of the Second Affiliated Hospital of Jiaxing University, from January 2010 to December 2020, and 84 patients with TETs were recruited for this study. Univariate and multivariate analyses were performed to determine the prognostic factors. The genetic polymorphism of MTHFR C667T was examined in the patients with TETs and in a group of healthy individuals. The correlation between MTHFR transcriptional levels and methylation was analyzed using The Cancer Genome Atlas (TCGA) thymoma dataset from the cBioPortal platform.

Results

Kaplan–Meier univariate survival analysis showed that sex, age, the maximum tumor diameter, surgery, chemotherapy, radiotherapy, WHO histological classification, Masaoka–Koga stage, and 8th UICC/AJCC TNM staging, were statistically significantly correlated with the prognosis of patients with TETs. The Masaoka–Koga stage and 8th UICC/AJCC TNM staging were strongly correlated with each other in this study (r=0.925, P<0.001). Cox multivariate survival analysis showed that the maximum tumor diameter, Masaoka–Koga stage, and 8th UICC/AJCC TNM staging were independent prognostic factors affecting the overall survival (OS) of patients with TETs (P<0.05). The MTHFR C667T genotype (χ^{2 =} 7.987, P=0.018) and allele distribution (χ^{2 =} 5.750, P=0.016) were significantly different between the patients and healthy controls. CT heterozygous and TT homozygous genotypes at this MTHFR polymorphism significantly increased the risk of TETs (odds ratio [OR] =4.721, P=0.008). Kaplan–Meier univariate survival analysis showed that there was no correlation between different genotypes and the prognosis of TETs (CC versus CT + TT, χ^{2 =}0.003, P=0.959). Finally, a negative correlation between the transcriptional and methylation levels of MTHFR was observed in the TCGA thymoma dataset (r=-0.24, P=0.010).

Conclusions

The Masaoka–Koga stage, 8th UICC/AJCC TNM staging, and maximum tumor diameter were independent prognostic factors for TETs. Reduced methylation levels of MTHFR and particular polymorphic variants may contribute to the susceptibility to developing TETs.

A novel risk classifier for predicting the overall survival of patients with thymic epithelial tumors based on the eighth edition of the TNM staging system: A population-based study

OBJECTIVE

Thymic epithelial tumors (TETs) are rare tumors that originated from thymic epithelial cells, with limited studies investigating their prognostic factors. This study aimed to investigate the prognostic factors of TETs and develop a new risk classifier to predict their overall survival (OS).

METHODS

This retrospective study consisted of 1224 TETs patients registered in the Surveillance, Epidemiology, and End Results (SEER) database, and 75 patients from the First Affiliated Hospital of Xi'an Jiaotong University. The univariate and multivariate Cox regression analyses were adopted to select the best prognostic variables. A nomogram was developed to predict the OS of these patients. The discriminative and calibrated abilities of the nomogram were assessed using the receiver operating characteristics curve (ROC) and calibration curve. Decision curve analysis (DCA), net reclassification index (NRI), and integrated discrimination improvement (IDI) were adopted to assess its net clinical benefit and reclassification ability.

RESULTS

The multivariate analysis revealed that age, sex, histologic type, TNM staging, tumor grade, surgery, radiation, and tumor size were independent prognostic factors of TETs, and a nomogram was developed to predict the OS of these patients based on these variables. The time-dependent ROC curves displayed that the nomogram yielded excellent performance in predicting the 12-, 36- and 60-month OS of these patients. Calibration curves presented satisfying consistencies between the actual and predicted OS. DCA illustrated that the nomogram will bring significant net clinical benefits to these patients compared to the classic TNM staging system. The estimated NRI and IDI showed that the nomogram could significantly increase the predictive ability of 12-, 36- and 60-month OS compared to the classic TNM staging system. Consistent findings were discovered in the internal and external validation cohorts.

CONCLUSION

The constructed nomogram is a reliable risk classifier to achieve personalized survival probability prediction of TETs, and could bring significant net clinical benefits to these patients.

Liver metastasis mimicking a liver cyst of a thymoma in a 38-year-old immunocompromised patient

Cystic liver lesions (CLL) are common and, in the majority of cases, benign. However, the range of differential diagnoses of CLL is wide. A combination of medical history, blood test results, and imaging can help find the correct diagnosis. We report the case of a 38-year-old immunocompromised female patient with a history of thymectomy and postoperative radiation 3 years prior due to thymoma. Subsequently, the patient was referred to our department for clarification of a cystic liver lesion. During short-term follow-up, the lesion increased in size, and due to the contrast agent behavior in the ultrasound and MRI examination, the suspicion of a biliary cystadenocarcinoma was considered.Furthermore, imaging showed several subcentimetric liver lesions of unknown dignity. Finally, pericystectomy and atypical partial liver resection was performed. Histology revealed a cystic metastasis of the malignant B3 thymoma and a cavernous hemangioma. Liver metastases of a thymoma are rare, and this is the first case of a cystic liver metastasis of a thymoma. The presented case illustrates that in the management of CLLs beside imaging techniques, the medical history with previous conditions should be considered, especially in past malignancies.

The incidence and prognosis of thymic squamous cell carcinoma: A Surveillance, Epidemiology, and End Results Program population-based study

BACKGROUND

Thymic carcinoma represents a rare type of malignant mediastinal tumor and has been the subject of controversy. Although independent prognostic factors related to thymic carcinoma have been investigated previously, few studies have focused specifically on the survival outcomes associated with thymic squamous cell carcinoma (TSCC). This study aims at presenting a survival analysis in this rare malignant disease at population level.

METHODS

We extracted the data of 216 patients with TSCC recorded from 1973 to 2015 from the Surveillance, Epidemiology, and End Results (SEER) database of the National Cancer Institute. The patients' demographic features, clinical traits, and treatment factors were analyzed in order to identify prognostic factors, which correlate overall survival using the Kaplan-Meier method as well as a multivariate Cox regression model, for TSCC.

RESULTS

The majority of patients were male, Caucasian, married, and insured. Furthermore, 58.3%, 54.6%, and 59.7% of patients TSCC underwent surgery, radiotherapy, and chemotherapy respectively. In a multivariate analysis, age of diagnosis (hazard ratio [HR]: 1.022, 95% confidence interval [CI]: 1.003-1.040, P = .020), surgical treatment (HR: 0.282, 95% CI: 0.164-0.484, P = .000), and stage (regional vs distant HR: 0.532, 95% CI: 0.324-0.872, P = .013; localized vs distant HR: 0.297, 95% CI: 0.133-0.664, P = .003) correlated with increased overall survival, whereas adjuvant therapy, including chemotherapy and radiotherapy, did not correlate with survival. Among surgically treated patients, age of diagnosis and stage were associated with better overall survival, while chemotherapy and radiotherapy did not contribute significantly to overall survival.

CONCLUSION

Surgery, age of diagnosis, and stage were associated with better overall survival among TSCC.

[Extended Resection of Locally Advanced Thymic Tumours in Stage III]

In the treatment of locally advanced thymic tumours, specific diagnostic testing is required, with a multimodal therapeutic approach consisting of surgery, radio- and/or chemotherapy. The complete resection of the tumour represents the most important prognostic factor with regard to recurrence-free and long-term survival. Local invasive growth of malignant thymic tumours into neighbouring mediastinal structures is classified as Masaoka-Koga stage III. Surgical resection can be performed primarily or after induction therapy, depending on the extent of the tumour. However, in some cases these tumours must be classified as non-resectable, so that only palliative radio-/chemotherapy remains as therapeutic option. TNM classification for malignant thymic tumours has been recently introduced. This resembles the established Masaoka-Koga classification in many aspects, but also includes some therapy-relevant changes. A differentiation is made between stages IIIA and IIIB, with the aim of assessing the resectability of advanced thymic tumours in a more differentiated manner and consequent planning of the therapy concept. Besides the thymus, thymoma, perithymic tissue, mediastinal pleura (stage I) or pericardium (stage II), all infiltrated structures should be removed "en bloc", if possible in stage III tumours. While the lung, brachiocephalic vessels or extrapericardial pulmonary vessels can still be resected and reconstructed if necessary, infiltration of the aorta or intrapericardial pulmonary vessels often limits macroscopically complete resection.

Radiographic Assessment of Objective Responses Using the ITMIG-Modified Criteria in Thymic Carcinoma

INTRODUCTION

Pleural metastases are common among patients with thymic carcinoma. Accurate and consistent measurement of pleural lesions is often difficult because of their unique locations and growth patterns. To minimize intraobserver variability, the International Thymic Malignancies Interest Group (ITMIG) proposed modified criteria for measurement of tumor response for thymic epithelial tumors.

METHODS

We conducted a retrospective review of the medical records of advanced or recurrent thymic carcinoma patients treated with chemotherapy between 1980 and 2016 in our institution. The best objective responses were assessed using the Response Evaluation Criteria in Solid Tumor version 1.1 (RECIST 1.1) and the ITMIG-modified criteria.

RESULTS

A total of 26 patients were included in the present study. According to the RECIST criteria, 1 (3.8%) patient showed complete response (CR), and 13 (50.0%), 10 (38.5%), and 2 (7.7%) showed partial response (PR), stable disease (SD), and progressive disease (PD), respectively. All 26 patients had the same best overall response using the ITMIG criteria. The median time to progression (TTP) according to the RECIST criteria and the ITMIG-modified criteria was 5.5 months (95% confidence interval [CI] 3.8-8.6) and 7.0 months (95% CI 3.8-9.3), respectively (p = 0.993).

CONCLUSION

The ITMIG-modified criteria showed a high concordance rate with RECIST 1.1 criteria in response assessment of thymic carcinoma.

The role of targeted therapy in thymic carcinoma

Thymic carcinoma is a rare entity and can be distinguished from benign thymomas by their aggressive nature and poor prognosis. The National Comprehensive Cancer Network guidelines recommend resection followed by adjuvant platinum-based chemotherapy for resectable tumors. However, the outcomes for metastatic or relapsed thymic carcinomas are poor with no regimen showing a consistent benefit. Moreover, the relative rarity of these tumors makes clinical trials difficult. Molecular analysis of thymomas shows a high incidence of genetic mutations and targeted therapy holds promise. We will briefly outline and review the current role of targeted therapy in thymic cancer.

Prognostic Factors and Efficacy of First-Line Chemotherapy in Patients with Advanced Thymic Carcinoma: A Retrospective Analysis of 286 Patients from NEJ023 Study

BACKGROUND

The prognostic factors and the efficacy of first-line chemotherapy remain unclear in patients with advanced thymic carcinoma.

MATERIALS AND METHODS

We conducted a multi-institutional retrospective study named NEJ023 for patients with advanced thymic carcinoma. All patients without any indication of curative treatment were treated with chemotherapy from 1995 to 2014 at 40 institutions of the North East Japan Study Group.

RESULTS

A total of 286 patients with advanced thymic carcinoma were analyzed. First-line chemotherapy included platinum-based doublets in 62.2% of the patients, monotherapy in 3.5%, and other multidrug chemotherapy (e.g., cisplatin, doxorubicin, vincristine, and cyclophosphamide [ADOC]) in 34.3%. The median follow-up period was 55.5 months, and the median overall survival (OS) from the start of first-line chemotherapy was 30.7 months (95% confidence interval, 25.9-35.9 months). There was no significant difference in OS among different first-line chemotherapy regimens (e.g., between carboplatin/paclitaxel and ADOC, median OS: 27.8 vs. 29.9 months). Masaoka-Koga stage IVa and volume reduction surgery were favorable prognostic factors for OS in the multivariate analysis using the Cox proportional hazards model.

CONCLUSION

The efficacy of each first-line chemotherapy regimen for advanced thymic carcinoma did not vary significantly. Our results might support the adequacy of the use of carboplatin/paclitaxel as first-line chemotherapy for these patients.

IMPLICATIONS FOR PRACTICE

Because of its rarity, there is limited information about prognostic factors and efficacy of chemotherapy in patients with advanced thymic carcinoma. This is the largest data set for those patients treated with chemotherapy. This study suggests there is no significant difference in efficacy between carboplatin/paclitaxel and cisplatin/doxorubicin/vincristine/cyclophosphamide for advanced thymic carcinoma. This result can support the adequacy of the selection of platinum doublets as treatment for those patients, rather than anthracycline-based multidrug regimen.