A Recurrence Predictive Model for Thymic Tumors and Its Implication for Postoperative Management: a Chinese Alliance for Research in Thymomas Database Study

Contrast-enhanced CT-based radiomics differentiate anterior mediastinum lymphoma from thymoma without myasthenia gravis and calcification

AIM

To explore the value of a radiomics model based on enhanced computed tomography (CT) in differentiating anterior mediastinal lymphoma (AML) and thymoma without myasthenia gravis (MG) and calcification.

MATERIALS AND METHODS

The present study analysed patients who were diagnosed histologically with AML and thymoma in three independent institutions. All pre-treatment patients underwent enhanced CT. In the training group of patients from institutions 1 (the First Affiliated Hospital of Kunming Medical University) and 3 (the Yunnan Cancer Hospital), two radiologists independently analysed the enhanced CT images and performed manual segmentation of each tumour. Radiomics features were screened using interobserver interclass coefficient (ICC) analysis, feature correlation analysis, and L1 regularisation. The discriminative efficacy of the logistic regression model was evaluated using receiver operating characteristic (ROC) analysis. Validation group of patients from institution 2 (the Second Affiliated Hospital of Zhejiang University School of Medicine) was used to validate the proposed models.

RESULTS

A total of 114 patients were enrolled in this study and 1,743 radiomics features were extracted from the enhanced CT images. After feature screening, the remaining 37 robust radiomics features were used to construct the model. In the training group, the AUC of the model was 0.987 (95% confidence interval [CI]: 0.976-0.999), the sensitivity, specificity, and accuracy were 0.912, 0.946, and 0.924, respectively. In the validation group, the AUC of the model was 0.798 (95% CI: 0.683-0.913), the sensitivity, specificity, and accuracy were 0.760, 0.700, and 0.743, respectively.

CONCLUSION

The radiomics model created provided effective information to assist in the selection of clinical strategies, thus reducing unnecessary procedures in patients with AML and guiding direct surgery in patients with thymoma to avoid biopsy.

Diagnostic performance of radiomics model for preoperative risk categorization in thymic epithelial tumors: a systematic review and meta-analysis

BACKGROUND

Incidental thymus region masses during thoracic examinations are not uncommon. The clinician's decision-making for treatment largely depends on imaging findings. Due to the lack of specific indicators, it may be of great value to explore the role of radiomics in risk categorization of the thymic epithelial tumors (TETs).

METHODS

Four databases (PubMed, Web of Science, EMBASE and the Cochrane Library) were screened to identify eligible articles reporting radiomics models of diagnostic performance for risk categorization in TETs patients. The quality assessment of diagnostic accuracy studies 2 (QUADAS-2) and radiomics quality score (RQS) were used for methodological quality assessment. The pooled area under the receiver operating characteristic curve (AUC), sensitivity and specificity with their 95% confidence intervals were calculated.

RESULTS

A total of 2134 patients in 13 studies were included in this meta-analysis. The pooled AUC of 11 studies reporting high/low-risk histologic subtypes was 0.855 (95% CI, 0.817-0.893), while the pooled AUC of 4 studies differentiating stage classification was 0.826 (95% CI, 0.817-0.893). Meta-regression revealed no source of significant heterogeneity. Subgroup analysis demonstrated that the best diagnostic imaging was contrast enhanced computer tomography (CECT) with largest pooled AUC (0.873, 95% CI 0.832-0.914). Publication bias was found to be no significance by Deeks' funnel plot.

CONCLUSIONS

This present study shows promise for preoperative selection of high-risk TETs patients based on radiomics signatures with current available evidence. However, methodological quality in further studies still needs to be improved for feasibility confirmation and clinical application of radiomics-based models in predicting risk categorization of the thymic epithelial tumors.

Development and validation of web-based dynamic nomograms predictive of disease-free and overall survival in patients who underwent pneumonectomy for primary lung cancer

Background

The tumour-node-metastasis (TNM) staging system is insufficient to precisely distinguish the long-term survival of patients who underwent pneumonectomy for primary lung cancer. Therefore, this study sought to identify determinants of disease-free (DFS) and overall survival (OS) for incorporation into web-based dynamic nomograms.

Methods

The clinicopathological variables, surgical methods and follow-up information of 1,261 consecutive patients who underwent pneumonectomy for primary lung cancer between January 2008 and December 2018 at Sun Yat-sen University Cancer Center were collected. Nomograms for predicting DFS and OS were built based on the significantly independent predictors identified in the training cohort (n = 1,009) and then were tested on the validation cohort (n = 252). The concordance index (C-index) and time-independent area under the receiver-operator characteristic curve (AUC) assessed the nomogram's discrimination accuracy. Decision curve analysis (DCA) was applied to evaluate the clinical utility.

Results

During a median follow-up time of 40.5 months, disease recurrence and death were observed in 446 (35.4%) and 665 (52.7%) patients in the whole cohort, respectively. In the training cohort, a higher C-reactive protein to albumin ratio, intrapericardial pulmonary artery ligation, lymph node metastasis, and adjuvant therapy were significantly correlated with a higher risk for disease recurrence; similarly, the independent predictors for worse OS were intrapericardial pulmonary artery and vein ligation, higher T stage, lymph node metastasis, and no adjuvant therapy. In the validation cohort, the integrated DFS and OS nomograms showed well-fitted calibration curves and yielded good discrimination powers with C-index of 0.667 (95% confidence intervals CIs [0.610-0.724]) and 0.697 (95% CIs [0.649-0.745]), respectively. Moreover, the AUCs for 1-year, 3-year, and 5-year DFS were 0.655, 0.726, and 0.735, respectively, and those for 3-year, 5-year, and 10-year OS were 0.741, 0.765, and 0.709, respectively. DCA demonstrated that our nomograms could bring more net benefit than the TNM staging system.

Conclusions

Although pneumonectomy for primary lung cancer has brought encouraging long-term outcomes, the constructed prediction models could assist in precisely identifying patients at high risk and developing personalized treatment strategies to further improve survival.

Prognostic factors and role of postoperative radiotherapy in surgically resected thymomas

Objective

To investigate the prognostic factors in and role of postoperative radiotherapy (PORT) for surgically resected thymomas.

Methods

A total of 1540 patients with pathologically confirmed thymomas undergoing resection between 2000 and 2018 were identified retrospectively from the SEER (Surveillance, Epidemiology, and End Results) database. Tumors were restaged as local (limited to thymus), regional (invasion to mediastinal fat and other neighboring structures), or distant stage. Disease-specific survival (DSS) and overall survival (OS) were estimated by the Kaplan-Meier method and the log-rank test. Adjusted hazard ratios (HRs) with 95% CIs were calculated by Cox proportional hazards modeling.

Results

Tumor stage and histology were independent predictors of both DSS (regional: HR, 3.711; 95% CI, 2.006-6.864; distant: HR, 7.920; 95% CI, 4.061-15.446; type B2/B3: HR, 1.435; 95% CI, 1.008-2.044) and OS (regional: HR, 1.461; 95% CI, 1.139-1.875; distant: HR, 2.551; 95% CI, 1.855-3.509; type B2/B3: HR, 1.409; 95% CI, 1.153-1.723). For patients with regional stage and type B2/B3 thymomas, PORT was associated with better DSS after thymectomy/thymomectomy (HR, 0.268; 95% CI, 0.099-0.727), but the association was not significant after extended thymectomy (HR, 1.514; 95% CI, 0.516-4.44). Among patients with lymph node metastases, those who received PORT (HR, 0.372; 95% CI, 0.146-0.949), chemotherapy (HR, 0.843; 95% CI, 0.303-2.346), or both (HR, 0.296, 95% CI, 0.071-1.236) had a better OS.

Conclusions

The extent of invasion and tumor histology were independent predictors of worse survival following surgical resection of thymoma. Patients with regional invasion and type B2/B3 thymoma who undergo thymectomy/thymomectomy may benefit from PORT, while patients with nodal metastases may benefit from multimodal therapy, including PORT and chemotherapy.

Nomogram to Predict Recurrence and Guide a Pragmatic Surveillance Strategy After Resection of Hepatoid Adenocarcinoma of the Stomach: A Retrospective Multicenter Study

BACKGROUND

An accurate recurrence risk assessment system and surveillance strategy for hepatoid adenocarcinoma of the stomach (HAS) remain poorly defined. This study aimed to develop a nomogram to predict postoperative recurrence of HAS and guide individually tailored surveillance strategies.

METHODS

The study enrolled all patients with primary HAS who had undergone curative-intent resection at 14 institutions from 2004 to 2019. Clinicopathologic variables with statistical significance in the multivariate Cox regression were incorporated into a nomogram to build a recurrence predictive model.

RESULTS

The nomogram of recurrence-free survival (RFS) based on independent prognostic factors, including age, preoperative carcinoembryonic antigen, number of examined lymph nodes, perineural invasion, and lymph node ratio, achieved a C-index of 0.723 (95% confidence interval [CI], 0.674-0.772) in the whole cohort, which was significantly higher than those of the eighth American Joint Committed on Cancer (AJCC) staging system (C-index, 0.629; 95% CI, 0.573-0.685; P < 0.001). The nomogram accurately stratified patients into low-, middle-, and high-risk groups of postoperative recurrence. The postoperative recurrence risk rates for patients in the middle- and high-risk groups were respectively 3 and 10 times higher than for the low-risk group. The patients in the middle- and high-risk groups showed more recurrence and metastasis, particularly multiple site metastasis, within 36 months after the operation than those in the low-risk group (low, 2.2%; middle, 8.6%; high, 24.0%; P = 0.003).

CONCLUSIONS

The nomogram achieved good prediction of postoperative recurrence for the patients with HAS after radical resection. For the middle- and high-risk patients, more active surveillance and targeted examination methods should be adopted within 36 months after the operation, particularly for liver and multiple metastases.

Real-world study of treatment and outcome of type B2 + B3 thymoma: The neglected part of thymoma

BACKGROUND

This study aimed to examine the treatment and prognosis of patients with type B2 + B3 thymoma and compare it with those patients with type B2 and B3 thymoma.

METHODS

We conducted a retrospective analysis of the results of 39 patients with type B2 + B3 thymoma, 133 patients with type B2 thymoma, and 64 patients with type B3 thymoma. The Kaplan-Meier technique was used to generate survival curves. For multivariate analysis, the Cox proportional hazard model was applied.

RESULTS

With a median follow-up of 60 months (range: 1-128 months), the percentage of patients with tumor, node, metastasis (TNM) stage III and IV disease gradually increased from 19.5% to 25.6% to 35.9% among those with histological subtypes B2, B2 + B3, and B3, respectively, p = 0.045. Twenty-three patients experienced recurrence or metastasis. The total 10-year progression-free survival (PFS) rates were 86.0% overall (85.0% in type B2, 87.2% in type B2 + B3, and 87.5% in type B3). Age, R0 resection, and Masaoka-Koga stage were found to have a significant on PFS in all patients. There was no statistically significant difference in PFS between different histotypes of thymoma, p = 0.650. PFS was predicted by R0 resection in all histotypes and by the Masaoka-Koga stage in the type B2 subgroup.

CONCLUSION

Combining the two staging methods to guide the diagnosis and treatment of patients with B2 + B3 thymoma is recommended. R0 resection is recommended to reduce recurrence. Patients with B2 + B3 thymoma have a prognosis similar to those with a B2 thymoma or a B3 thymoma alone.

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.

Radiomics Analysis of Multiphasic Computed Tomography Images for Distinguishing High-Risk Thymic Epithelial Tumors From Low-Risk Thymic Epithelial Tumors

OBJECTIVES

The objective of this study is to preoperatively investigate the value of multiphasic contrast-enhanced computed tomography (CT)-based radiomics signatures for distinguishing high-risk thymic epithelial tumors (HTET) from low-risk thymic epithelial tumors (LTET) compared with conventional CT signatures.

MATERIALS AND METHODS

Pathologically confirmed 305 thymic epithelial tumors (TETs), including 147 LTET (Type A/AB/B1) and 158 HTET (Type B2/B3/C), were retrospectively analyzed, and were randomly divided into training (n = 214) and validation cohorts (n = 91). All patients underwent nonenhanced, arterial contrast-enhanced, and venous contrast-enhanced CT analysis. The least absolute shrinkage and selection operator regression with 10-fold cross-validation was performed for radiomic models building, and multivariate logistic regression analysis was performed for radiological and combined models building. The performance of the model was evaluated by the area under the receiver operating characteristic curve (AUC of ROC), and the AUCs were compared using the Delong test. Decision curve analysis was used to evaluate the clinical value of each model. Nomogram and calibration curves were plotted for the combined model.

RESULTS

The AUCs for radiological model in the training and validation cohorts were 0.756 and 0.733, respectively. For nonenhanced, arterial contrast-enhanced, venous contrast-enhanced CT and 3-phase images combined radiomics models, the AUCs were 0.940, 0.946, 0.960, and 0.986, respectively, in the training cohort, whereas 0.859, 0.876, 0.930, and 0.923, respectively, in the validation cohort. The combined model, including CT morphology and radiomics signature, showed AUCs of 0.990 and 0.943 in the training and validation cohorts, respectively. Delong test and decision curve analysis showed that the predictive performance and clinical value of the 4 radiomics models and combined model were greater than the radiological model ( P < 0.05).

CONCLUSIONS

The combined model, including CT morphology and radiomics signature, greatly improved the predictive performance for distinguishing HTET from LTET. Radiomics texture analysis can be used as a noninvasive method for preoperative prediction of the pathological subtypes of TET.

The Value of Postoperative Radiotherapy in Thymoma Patients with Myasthenia Gravis

INTRODUCTION

Surgery is the first-line treatment for patients with thymoma associated with myasthenia gravis (MG); however, the value of radiotherapy among these patients remains debatable. Herein, we examined the impact of postoperative radiotherapy (PORT) on the efficacy and prognosis of patients with thymoma and MG.

METHODS

This retrospective cohort study included 126 patients with thymoma and MG who were enrolled in the Xiangya Hospital clinical database between 2011 and 2021. Demographic and clinical data were collected including sex, age, histologic subtype, Masaoka-Koga staging, primary tumor, lymph node, metastasis (TNM) staging, and therapeutic modalities. To evaluate short-term MG symptom improvement following PORT, we examined changes in the quantitative myasthenia gravis (QMG) scores within 3 months post-treatment. Minimal manifestation status (MMS) was the main endpoint for assessing long-term improvement in MG symptoms. Overall survival (OS) and disease-free survival (DFS) were primary endpoints to determine the impact of PORT on prognosis.

RESULTS

Effects of PORT on MG symptoms: QMG scores significantly differed between the non-PORT and PORT groups (χ2= 6.300, p = 0.012). The median time to achieve MMS was significantly shorter in the PORT group than that in the non-PORT group (2.0 years vs. 4.4 years; p = 0.031). Multivariate analysis revealed that radiotherapy was associated with a reduced time to achieve MMS (hazard ratio [HR] 1.971, 95% confidence interval [CI]:1.102-3.525, p = 0.022). Effects of PORT on DFS and OS: The 10-year OS rate of the entire cohort was 90.5%, whereas OS rates for the PORT and non-PORT groups were 94.4 and 85.1%, respectively. The 5-year DFS rates for the whole cohort, PORT group, and non-PORT group were 89.7, 95.8, and 81.5%, respectively. PORT was associated with improved DFS (HR 0.139, 95% CI: 0.037-0.533, p = 0.004). In the high-risk histologic subgroup (type B2, B3), patients who received PORT had better OS (p = 0.015) and DFS (p = 0.0053) than those who did not receive PORT. PORT was associated with improved DFS (HR 0.232, 95% CI: 0.069-0.782, p = 0.018) in Masaoka-Koga stages II, III, and IV disease.

CONCLUSIONS

Overall, our findings indicate that PORT positively impacts thymoma patients with MG, particularly those with a higher histologic subtype and Masaoka-Koga staging.

Minimally Invasive Thymectomy Could Be Attempted for Locally Advanced Thymic Malignancies: A Real-World Study With Propensity Score-Matched Analysis

INTRODUCTION

Increasing evidence supports minimally invasive thymectomy (MIT) for early stage thymic malignancies than open median sternotomy thymectomy (MST). Nevertheless, whether MIT could be attempted for locally advanced disease remains unclear.

METHODS

The clinical data of consecutive patients with stage T2-3NxM0 (eighth edition TNM staging) thymic malignancies who underwent MIT or MST were identified from a prospectively maintained database. The co-resected structures were rated with a resection index to evaluate surgical difficulty. The impact of surgical approach on treatment outcomes was investigated through propensity score-matched analysis and multivariable analysis.

RESULTS

From January 2008 to December 2019, a total of 128 patients were included; MIT was initially attempted in 58 (45.3%) cases, and eight (13.8%) were converted to MST during surgery. The conversion group had similar perioperative outcomes to the MST group, except for a longer operation time. After propensity score matching, the resection index scores were similar between the MIT and MST groups (3.5 versus 3.7, p = 0.773). The MIT group had considerably less blood loss (p < 0.001), fewer postoperative complications (p = 0.048), a shorter duration of chest drainage (p < 0.001), and a shorter hospitalization duration (p < 0.001) than the MST group. The 5-year freedom from recurrence rate was not different between the two groups (78.2% versus 78.5%, p = 0.942). In multivariable analysis, surgical approach was not associated with freedom from recurrence (p = 0.727).

CONCLUSIONS

MIT could be safely attempted in carefully selected patients with locally advanced thymic tumors. Conversion did not compromise the surgical outcomes. Patients may benefit from the less traumatic procedure and thus better recovery, with comparable long-term oncologic outcomes.

Failure patterns for thymic carcinoma with completed resection and postoperative radiotherapy

BACKGROUND AND PURPOSE

We aimed to evaluate the pattern and risk factors of disease failure in patients with thymic carcinoma after complete resection and postoperative radiotherapy (PORT).

MATERIALS AND METHODS

We retrospectively analyzed 127 patients with thymic carcinoma who underwent PORT after complete resection between 2003 and 2020 in our center. Data on clinical characteristics and radiation fields were collected. Failure patterns were recorded as locoregional (disease appearing in the tumor bed or regional lymph nodes), pleural, or distant failure (including hematogenous metastasis and nonregional lymph node metastasis).

RESULTS

All patients underwent tumor bed irradiation. During a median follow-up period of 64 months, disease failure was observed in 51 patients (40.2 %). The 5-year disease-free survival (DFS) and overall survival rates were 58.9 % and 85.0 %, respectively. The sequence of failure patterns was distant (n = 41, 32.3 %), pleural (n = 28, 22.0 %), and locoregional failure (n = 19, 15.0 %). Of the locoregional failure patients, failures occurred in-field in three patients (2.4 %), marginal failure in one patient (0.8 %), out-of-field failure in nine patients (7.1 %), synchronous in-field and out-of-field failures in two patients (1.6 %), synchronous marginal and out-of-field failures in two patients (1.6 %), and unknown failure fields in two patients (1.6 %). Multivariate analysis showed that Masaoka stage (hazard ratio [HR], 3.88; p = 0.000) and adjuvant chemotherapy (HR, 0.47; p = 0.015) were independent predictors of DFS.

CONCLUSION

The most common failure was distant, the Masaoka stage and adjuvant chemotherapy were independent predictors of DFS, and low locoregional failure-supported tumor bed irradiation was sufficient for patients with thymic carcinoma after complete resection.

Diagnostic value of apparent diffusion coefficient in predicting pathological T stage in patients with thymic epithelial tumor

Purposes

This study aimed to evaluate the diagnostic capacity of apparent diffusion coefficient (ADC) in predicting pathological Masaoka and T stages in patients with thymic epithelial tumors (TETs).

Methods

Medical records of 62 patients who were diagnosed with TET and underwent diffusion-weighted imaging (DWI) prior to surgery between August 2017 and July 2021 were retrospectively analyzed. ADC values were calculated from DWI images using b values of 0, 400, and 800 s/mm². Pathological stages were determined by histological examination of surgical specimens. Cut-off points of ADC values were calculated via receiver operating characteristic (ROC) analysis.

Results

Patients had a mean age of 56.3 years. Mean ADC values were negatively correlated with pathological Masaoka and T stages. Higher values of the area under the ROC curve suggested that mean ADC values more accurately predicated pathological T stages than pathological Masaoka stages. The optimal cut-off points of mean ADC were 1.62, 1.31, and 1.48 × 10^–3 mm²/sec for distinguishing pathological T2-T4 from pathological T1, pathological T4 from pathological T1-T3, and pathological T3-T4 from pathological T2, respectively.

Conclusion

ADC seems to more precisely predict pathological T stages, compared to pathological Masaoka stage. The cut-off values of ADC identified may be used to preoperatively predict pathological T stages of TETs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40644-022-00495-x.

Promotor methylation status of MAPK4 is a novel epigenetic biomarker for prognosis of recurrence in patients with thymic epithelial tumors

BACKGROUND

The prognosis of thymic epithelial tumors (TETs) currently relies on the commonly adopted WHO classification and Masaoka staging system, which cannot reflect the undefined biological behaviors limiting them as prognostic factors.

METHODS

In this study, we first identified 40 genes and 179 genes, respectively that were epigenetically upregulated and silenced, corresponding to a total of 509 functionally methylated CpG sites between thymomas and thymic carcinomas by using the TCGA dataset.

RESULTS

The methylation β-values of cg20068620 in MAPK4 and cg18770944 in USP51 were significantly associated with recurrence-free survival (RFS). In the independent validation cohort, only WHO classification and methylation β-values of cg20068620 in MAPK4 were independent prognostic factors for RFS in Chinese patients with TETs. A linear weighted model including these two factors was used to calculate the recurrence risk score (RRS). Time-dependent ROC curve analysis revealed that RRS was overwhelmingly superior to WHO classification for predicting 3-, 5-, and 10-year RFS and Masaoka stage for 3- and 5-year RFS.

CONCLUSIONS

These results suggested that the methylation site cg20068620 in MAPK4 can improve the accuracy of the WHO classification alone regarding the prognostic value of TETs recurrence.

Hypofractionated Radiation Therapy Combined With Weekly Chemotherapy in Patients With Unresectable or Recurrent Thymic Epithelial Tumor: A Prospective, Single-Arm Phase 2 Study (GASTO-1042)

PURPOSE

This prospective phase 2 study aimed to evaluate the efficacy and safety of hypofractionated radiation therapy (HRT) combined with concurrent weekly chemotherapy in patients with unresectable or recurrent thymic epithelial tumors (TETs).

METHODS AND MATERIALS

Patients with unresectable or recurrent intrathoracic TETs that could be encompassed within the radiation fields were enrolled. HRT using intensity modulated radiation therapy (IMRT) technique was administered with 3 different levels of radiation doses (51 Gy/17 fractions (fx), 48 Gy/12 fx, and 45 Gy/9 fx; biologically effective dose of 66.3-67.5Gy), combined with weekly docetaxel (25 mg/m²) and nedaplatin (25 mg/m²). Weekly thymosin α1 (1.6 mg) was administered from the start to 2 months after radiation therapy. The objective response rate (ORR), progression-free survival (PFS), overall survival (OS), health-related quality of life (QOL), and toxicity were recorded.

RESULTS

Fifty eligible patients enrolled from August 1, 2018, to July 1, 2020, were analyzed. Most patients (82.0%) had stage IVB tumors. Patients had IMRT-HRT (36-51 Gy in 9-17 fx, median biologically effective dose of 67.2 Gy) and concurrent weekly docetaxel/nedaplatin (2-4 cycles). During a median follow-up of 25.0 months (14.0-40.0), the ORR was 83.7%, the 2-year PFS was 59.1%, and the 2-year OS was 90.0%. There was 1 (2.0%) in-field recurrence while 19 (38.0%) patients developed out-of-field recurrence. Grade 3 pneumonitis was observed in 1 patient (2.0%). The ORR, 2-year PFS, 2-year OS, and toxicity were similar among 3 dose levels. Fourteen (28.0%) patients had 2 to 4 courses of radiation therapy because of recurrent diseases. Only 1 suffered from grade 1 pulmonary fibrosis during follow-up. Most patients (88%) maintained a stable QOL within 1 year after radiation therapy.

CONCLUSIONS

IMRT-HRT and concurrent weekly docetaxel/nedaplatin was effective and well tolerated in unresectable or recurrent TETs. Considering the common out-of-field recurrence, this combined regimen could be an option for repeated radiation therapy. Thymosin α1 might help lower the incidence of pneumonitis and maintain the QOL.

Nomogram predicts the prognosis of patients with thymic carcinoma: A population-based study using SEER data

BACKGROUND

Thymic carcinoma (TC) is a rare malignant tumor that can have a poor prognosis, and accurate prognostication prediction remains difficult. We aimed to develop a nomogram to predict overall survival (OS) and cancer-specific survival (CSS) based on a large cohort of patients.

METHODS

The Surveillance Epidemiology and End Results (SEER) database was searched to identify TC patients (1975-2016). Univariate and multivariable Cox regression analyses were used to identify predictors of OS and CSS, which were used to construct nomograms. The nomograms were evaluated using the concordance index (C-index), calibration curve, receiver operating characteristic curve, and decision curve analysis (DCA). Subgroup analysis was performed to identify high-risk patients.

RESULTS

The analysis identified six predictors of OS (Masaoka stage, surgical method, lymph node metastasis, liver metastasis, bone metastasis, and radiotherapy) and five predictors of CSS (Masaoka stage, surgical method, lymph node metastasis, tumor size, and brain metastasis), which were used to create nomograms for predicting three-year and five-year OS and CSS. The nomograms had reasonable C-index values (OS: 0.687 [training] and 0.674 [validation], CSS: 0.712 [training] and 0.739 [validation]). The DCA curve revealed that the nomograms were better for predicting OS and CSS, relative to the Masaoka staging system.

CONCLUSION

We developed nomograms using eight clinicopathological factors that predicted OS and CSS among TC patients. The nomograms performed better than the traditional Masaoka staging system and could identify high-risk patients. Based on the nomograms' performance, we believe they will be useful prognostication tools for TC patients.

Prognostic Value of Preoperative Nutritional Assessment and Neutrophil-to-Lymphocyte Ratio in Patients With Thymic Epithelial Tumors

Introduction

Systemic nutrition and immune inflammation are the key factors in cancer development and metastasis. This study aimed to compare and assess four nutritional status and immune indicators: prognostic nutritional index (PNI), nutritional risk index (NRI), neutrophil-to-lymphocyte ratio (NLR), and the systemic immune-inflammatory index (SII) as prognostic indicators for patients with thymic epithelial tumors.

Materials

We retrospectively reviewed 154 patients who underwent thymic epithelial tumor resection at our hospital between 2004 and 2015. The optimal cutoff value for each nutritional and immune index was obtained using the X-tile software. Kaplan-Meier curves and Cox proportional hazards models were used for survival analysis.

Results

Univariate analysis showed that PNI, NRI, NLR, SII, albumin (ALB), the albumin/globulin ratio (A/G), WHO stage, T stage, and drinking history were associated with the overall survival (OS) of patients (P < 0.05). The NRI, NLR, A/G, ALB, T stage, and WHO stage were significant independent prognostic factors of OS in multivariate analysis (P < 0.05). Finally, we constructed a coNRI-NLR model to predict OS and recurrence-free survival (RFS).

Conclusions

This study suggests that the preoperative NRI, NLR, and coNRI-NLR model may be important prognostic factors for patients with thymic epithelial tumors who undergo surgical resection.

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.

Masaoka-Koga and TNM Staging System in Thymic Epithelial Tumors: Prognostic Comparison and the Role of the Number of Involved Structures

Simple Summary

Thymic epithelial tumors were originally staged using the Masaoka–Koga staging system, even if recently the adoption of the tumor node metastases staging system was recommended. However, it remains controversial as to which staging system is the most effective in prognosis prediction for these patients. The aim of this study was to analyze the prognostic effectiveness of these staging systems and to verify a possible improvement.

Abstract

Background: The aim of this study was to evaluate the Masaoka–Koga and the tumor node metastases (TNM) staging system in thymic epithelial tumors (TET) considering possible improvements. Methods: We reviewed the data of 379 patients who underwent surgical resection for TET from 1 January 1985 to 1 January 2018, collecting and classifying the pathological report according to the Masaoka–Koga and the TMN system. The number of involved organs was also considered as a possible prognostic factor and integrated in the two staging systems to verify its impact. Results: Considering the Masaoka–Koga system, 5- and 10-year overall survival (5–10YOS) was 96.4% and 88.9% in stage I, 95% and 89.5% in stage II and 85.4% and 72.8% in stage III (p = 0.01), with overlapping in stage I and stage II curves. Considering the TNM system, 5–10YOS was 95.5% and 88.8% in T1, 84.8% and 70.7% in T2 and 88% and 76.3% in T3 (p = 0.02), with overlapping T2–T3 curves. Including the number of involved structures, in Masaoka–Koga stage III, patients with singular involved organs had a 100% and 76.6% vs. 87.7% 5–10YOS, which was 76.6% in patients with multiple organ infiltration. Considering the TNM, T3 patients with singular involved structures presented a 5–10YOS of 100% vs. 62.5% and 37.5% in patients with multiple organ involvement (p = 0.07). Conclusion: The two staging systems present limitations due to overlapping curves in early Masaoka–Koga stages and in advanced T stages for TNM. The addition of the number of involved organs seems to be a promising factor for the prognosis stratification in these patients.

Survival impact of concurrent chemoradiotherapy for elderly patients with synchronous oligometastatic esophageal squamous cell carcinoma: A propensity score matching and landmark analyses

PURPOSE

To evaluate the potential benefits of concurrent chemoradiotherapy (CCRT), and to establish a nomogram for predicting survival outcomes of elderly patients with synchronous oligometastatic esophageal squamous cell carcinoma (SOEC).

MATERIALS AND METHODS

This study eventually enrolled 314 elderly patients who initially diagnosed with SOEC from two centers. Treatment responses and outcomes of 151 patients receiving CCRT and 163 patients undergoing chemotherapy alone (CT) were compared. Propensity score matching and landmark analyses were performed to control potential confounding factors. A nomogram was established on the basis of the Cox regression model.

RESULTS

After a median follow-up of 42.3 months, CCRT was superior to CT alone in objective response rate (ORR, 59.6% vs. 39.9%, P < 0.001), median progression-free survival (PFS, 10.0 vs. 7.2 months, P < 0.001), and median overall survival (OS, 18.5 vs. 15.6 months, P < 0.001). The propensity score matching (PSM) and landmark analyses redemonstrated the same trend (P < 0.01). On hierarchical analysis, patients with 1-3 metastatic lesions involving one organ displayed longer median PFS (9.0 vs. 7.8 months, P = 0.008) and OS (17.8 vs. 15.2 months, P < 0.001) than those with 4-5 metastatic lesions involving 2-3 organs. The major toxicities of grade III or higher for CCRT included leukocytopenia (23.2%), radiation esophagitis (7.3%), and radiation pneumonitis (8.6%). Cox multivariate analysis showed that the number of metastatic lesions (P = 0.012) and tumor response (P < 0.001) were independent prognostic factors associated with OS. A nomogram was established by incorporating the number of metastatic lesions and tumor response, with a concordance index of 0.743 after internal cross-validation. Calibration curves and decision curve analysis confirmed that nomogram had a favorable predictive value for individualized survival.

CONCLUSIONS

Compared with CT alone, CCRT exhibited superior efficacy and acceptable toxicity in the first-line treatment for elderly patients with SOEC. The current study supports the oligometastatic definition of ≤3 metastatic lesions involving one organ for esophageal cancer patients. The constructed nomogram can effectively predict the individualized survival.

Diagnostic and prognostic values of 2-[18F]FDG PET/CT in resectable thymic epithelial tumour

OBJECTIVES

We aimed to evaluate the diagnostic ability for the prediction of histologic grades and prognostic values on recurrence and death of pretreatment 2-[¹⁸F]FDG PET/CT in patients with resectable thymic epithelial tumours (TETs).

METHODS

One hundred and fourteen patients with TETs who underwent pretreatment 2-[¹⁸F]FDG PET/CT between 2012 and 2018 were retrospectively evaluated. TETs were classified into three histologic subtypes: low-risk thymoma (LRT, WHO classification A/AB/B1), high-risk thymoma (HRT, B2/B3), and thymic carcinoma (TC). Area under the receiver operating characteristics curve (AUC) was used to assess the diagnostic performance of PET/CT variables (maximum standardised uptake value [SUVmax], metabolic tumour volume [MTV], total lesion glycolysis [TLG], maximum diameter). Cox proportional hazards models were built using PET/CT and clinical variables.

RESULTS

The tumours included 52 LRT, 33 HRT, and 29 TC. SUVmax showed good diagnostic ability for differentiating HRT/TC from LRT (AUC 0.84, 95% confidence interval [CI] 0.76 - 0.92) and excellent ability for differentiating TC from LRT/HRT (AUC 0.94, 95% CI 0.90 - 0.98), with significantly higher values than MTV, TLG, and maximum diameter. With an optimal cut-off value of 6.4, the sensitivity, specificity, and accuracy for differentiating TC from LRT/HRT were 69%, 96%, and 89%, respectively. In the multivariable Cox proportional hazards analyses for freedom-from-recurrence, SUVmax was an independent prognostic factor (p < 0.001), whereas MTV and TLG were not. SUVmax was a significant predictor for overall survival in conjunction with clinical stage and resection margin.

CONCLUSION

SUVmax showed excellent diagnostic performance for prediction of TC and significant prognostic value in terms of recurrence and survival.

KEY POINTS

• Maximum standardised uptake value (SUVmax) shows excellent performance in the differentiation of thymic carcinoma from low- and high-risk thymoma. • SUVmax is an independent prognostic factor for freedom-from-recurrence in the multivariable Cox proportional hazard model and a significant predictor for overall survival. • 2-[¹⁸F]FDG PET/CT can provide a useful diagnostic and prognostic imaging biomarker in conjunction with histologic classification and stage and help choose appropriate management for thymic epithelial tumours.

Nomogram predict relapse-free survival of patients with thymic epithelial tumors after surgery

Background

Hematological indicators and clinical characteristics play an important role in the evaluation of the progression and prognosis of thymic epithelial tumors. Therefore, we aimed to combine these potential indicators to establish a prognostic nomogram to determine the relapse-free survival (RFS) of patients with thymic epithelial tumors undergoing thymectomy.

Methods

This retrospective study was conducted on 156 patients who underwent thymectomy between May 2004 and August 2015. Cox regression analysis were performed to determine the potential indicators related to prognosis and combine these indicators to create a nomogram for visual prediction. The prognostic predictive ability of the nomogram was evaluated using the consistency index (C-index), receiver operating characteristic (ROC) curve, and risk stratification. Decision curve analysis was used to evaluate the net benefits of the model.

Results

Preoperative albumin levels, neutrophil-to-lymphocyte ratio (NLR), T stage, and WHO histologic types were included in the nomogram. In the training cohort, the nomogram showed well prognostic ability (C index: 0.902). Calibration curves for the relapse-free survival (RFS) were in good agreement with the standard lines in training and validation cohorts.

Conclusions

Combining clinical and hematologic factors, the nomogram performed well in predicting the prognosis and the relapse-free survival of this patient population. And it has potential to identify high-risk patients at an early stage. This is a relatively novel approach for the prediction of RFS in this patient population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08585-y.

Vascular Involvement in Thymic Epithelial Tumors: Surgical and Oncological Outcomes

BACKGROUND

The involvement of mediastinal great vessels is common in advanced stage thymic tumors, which makes their surgical resection challenging. Moreover, the impact of vascular involvement on the oncological prognosis is still unclear. The aim of this study is to investigate the surgical and oncological outcomes and the impact of vascular involvement in a population of patients operated for advanced stage thymic tumors.

METHODS

A retrospective analysis on four hundred and sixty-five patients undergoing resection for advanced stage (Masaoka III-IV) thymic tumors in a single high-volume center was performed. One hundred forty-four patients met the inclusion criteria and were eligible for the study. Patients were divided in two groups according to the presence or absence of vascular involvement.

RESULTS

the two groups did not differ for the baseline characteristics and showed comparable surgical outcomes. Vascular involvement was not associated with worse overall survival but with an increased recurrence rate (p = 0.03). Multivariable analysis demonstrated a higher risk of recurrence in patients without R0 resection (HR 0.11, 0.02-0.54, p = 0.006) and with thymic carcinoma (HR 2.27, 1.22-4.24, p = 0.01).

CONCLUSIONS

resection of thymic tumors with vascular involvement can be performed with optimal surgical results in a high volume center. From the oncological point of view, the involvement of the great vessels seems to be associated with a higher recurrence rate without affecting long-term survival.

Surgical feasibility and long-term outcome of superior vena cava replacement for advanced thymoma in patients undergoing preoperative chemotherapy or chemoradiotherapy

Background

The aim of this study was to investigate the long‐term outcome of superior vena cava (SVC) replacement after chemotherapy or chemoradiotherapy for advanced thymoma.

Methods

The medical information of patients with advanced thymoma who underwent thymoma resection and SVC replacement in Beijing Tongren Hospital from 2002 to 2017 were reviewed. We compared surgical outcomes, postoperative complications and long‐term prognosis in the chemoradiotherapy + surgery group (CRT + surgery group, 19 cases) and the surgery group (26 cases).

Results

The operation time (486.05 ± 148.01 vs. 370.77 ± 124.32 min; p = 0.007) and intraoperative blood loss (1400 ml [IQR 1125–2105 ml] vs. 855 ml [IQR 555–1682.5 ml], p = 0.036), poor wound healing (three cases [15.79%] vs. zero cases [0.0%], p = 0.036) in the CRT + surgery group were significantly higher than those of the surgery group. There was no significant difference between the CRT + surgery group and the surgery group in postoperative chest tube drainage time, hospitalization time, postoperative arrhythmia and incidence of pneumonia. Kaplan Meier analysis showed that the recurrence‐free survival (RFS) curves of the CRT + surgery group patients were better than those of the surgery group (p = 0.031). However, overall survival (OS) between the two groups was not significantly different (p = 0.069).

Conclusions

Thymoma resection and SVC replacement is feasible for patients undergoing preoperative induction chemotherapy or chemoradiotherapy for advanced thymoma. Although patients in the CRT + surgery group had a longer operation time and increased intraoperative bleeding, the RFS rate seemed to be better than that in the surgery group.

Impact of expert pathologic review of thymic epithelial tumours on diagnosis and management in a real-life setting: A RYTHMIC study

BACKGROUND

Classification of thymic epithelial tumours (TETs) is known to be challenging; however, the level of discordances at a nationwide level between initial and expert diagnosis and their clinical consequences are currently unknown. RYTHMIC is a national network dedicated to the management of TET based on initial histological diagnosis, followed by an additional expert review of all cases. Our aim was to evaluate the discordances between initial and expert diagnoses and whether they would have led to different clinical management.

PATIENTS AND METHODS

We conducted a retrospective analysis of the cohort of patients discussed at RYTHMIC tumour board from January 2012 to December 2016. Assessment of disagreement was made for histological typing and for staging. The discordances were classified as major or minor based on whether they would have changed or not the proposed therapeutic strategy, respectively. Follow-up of the patients with major discordances was conducted until December 2018.

RESULTS

Four hundred sixty-seven patients were reviewed, and 183 (39%) discordances were identified either related to histological subtype (132) and/or stage (72). Major discordances were identified in 27 patients (6%). They included 16 patients with TET for whom treatment recommendation based on the central review would have been post-operative radiotherapy, whereas it had not been the case. However, follow-up did not show any progression among the 15 patients with high-grade histology and/or stage resected thymomas. On the other hand, among the remaining 11 patients including 7 with a diagnosis other than TET, the overall management or follow-up would have been completely different with the expert diagnosis.

CONCLUSION

Our real-life cohort reveals a high level of discordances considering TET diagnosis and supports expert review for optimal clinical management.