Influence of Smoking and Histologic Subtype on Developing Extrathymic Malignancy in Thymoma Patients

Prognostic impact of surgery on thymic malignancies with concurrent or previous extrathymic malignancies: a retrospective analysis from 1998 to 2021

OBJECTIVE

There is limited research on the impact of surgery on the cancer-specific survival (CSS) of patients with malignant thymoma and concurrent or previous extrathymic malignancies (PMTEMs). This retrospective analysis evaluated the prognostic value of surgery in PMTEMs.

METHODS

Data were sourced from the SEER database, encompassing PMTEMs aged 20-90 with confirmed diagnoses and comprehensive clinical information. Patients were categorized into surgical (n = 105) and nonsurgical (n = 25) groups. Propensity score matching (PSM) was employed to mitigate selection bias, resulting in well-balanced baseline characteristics between the groups. Kaplan-Meier curves and the log-rank test were used to investigate the prognostic value of surgery in PMTEMs.

RESULTS

Using PSM, the matching of characteristics between the surgical and nonsurgical groups was well-balanced, ensuring the reliability of subsequent analyses. Pre-PSM, the CSS in the surgical group was significantly better than that in the nonsurgical group (p <.001). Similarly, according to the post-PSM data, the CSS for PMTEMs in the surgical group remained superior to that in the nonsurgical group, which indicates that the survival advantage of the surgical group persisted after PSM (p =.030). Additionally, PMTEMs with smaller thymomas (≤ 5 cm) had a significant advantage in CSS compared to those with larger thymomas (p = .046).

CONCLUSIONS

In conclusion, this study shows that surgery may significantly improve the survival rate of PMTEMs.

Genomic landscape and molecularly informed therapy in thymic carcinoma and other advanced thymic epithelial tumors

BACKGROUND

Thymic epithelial tumors (TETs) are rare malignancies with limited treatment options and underexplored molecular features.

METHODS

We examined the genomic landscape and therapeutic outcomes in 81 patients with advanced TETs, including thymic carcinomas (TCs), thymomas, and thymic neuroendocrine neoplasms (TNENs), who were enrolled in the MASTER trial, a prospective observational precision oncology trial.

FINDINGS

Using whole-genome-sequencing and whole-exome-sequencing analysis, transcriptome analysis, and methylome analysis, we identified distinct molecular features across TET subtypes, including a higher tumor mutational burden in TC and pathogenic germline variants in 18% of cases. We performed transcriptome- and methylome-based unsupervised clustering and were able to divide TCs into immunologically hot and cold subsets, with hot TCs exhibiting higher T cell infiltration and significantly longer overall survival. In 65 out of 76 (86%) patients, we recommended molecularly informed therapies, which were applied in 29 out of 65 (45%) cases, leading to a disease control rate of 62% and an objective response rate of 23% (both n = 26). The progression-free survival ratio (PFSr) was > 1.3 in 8 out of 24 (33%) patients, 7 of them having TC. Among TCs, patients achieved a mean PFSr of 1.4, indicating potential therapeutic advantages in this subgroup. The PFSr between the PFS of immune checkpoint inhibition and preceding therapies was significantly higher in the hot cluster compared to the cold cluster (median 1.7 vs. 0.3; p = 0.01945).

CONCLUSIONS

Our findings expand the understanding of TET biology and emphasize the role of precision oncology in informing treatment decisions and improving outcomes for patients with advanced TETs, particularly in TCs.

Prognostic factors in patients with thymoma who underwent surgery

PURPOSE

Thymoma is the most common primary tumor in the anterior mediastinum. The prognostic factors of patients with thymoma still need to be clarified. In this study, we aimed to investigate the prognostic factors of patients with thymoma who received radical resection and establish the nomogram to predict the prognosis of these patients.

MATERIALS AND METHODS

Patients who underwent radical resection for thymoma with complete follow-up data between 2005 and 2021 were enrolled. Their clinicopathological characteristics and treatment methods were retrospectively analyzed. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared by the log-rank test. Univariate and multivariate Cox proportional hazards regression analyses were performed to identify the independent prognostic factors. According to the results of the univariate analysis in the Cox regression model, the predictive nomograms were created.

RESULTS

A total of 137 patients with thymoma were enrolled. With a median follow-up of 52 months, the 5-year and 10-year PFS rates were 79.5% and 68.1%, respectively. The 5-year and 10-year OS rates were 88.4% and 73.1%, respectively. Smoking status (P = 0.022) and tumor size (P = 0.039) were identified as independent prognostic factors for PFS. Multivariate analysis showed that a high level of neutrophils (P = 0.040) was independently associated with OS. The nomogram showed that the World Health Organization (WHO) histological classification contributed more to the risk of recurrence than other factors. Neutrophil count was the most important predictor of OS in patients with thymoma.

CONCLUSION

Smoking status and tumor size are risk factors for PFS in patients with thymoma. A high level of neutrophils is an independent prognostic factor for OS. The nomograms developed in this study accurately predict PFS and OS rates at 5 and 10 years in patients with thymoma based on individual characteristics.

Uniportal video-assisted thoracic surgery approach for simultaneous lung cancer and thymic carcinoma: Case report and literature review

Thymic carcinoma is an epithelial tumor derived from thymic epithelial cells. Thymic tumors may be associated with other simultaneous and/or metachronous extra‐thymic tumors (e.g., lung cancer). Here, we report a case of simultaneous surgical management of lung and mediastinal neoplasm together with a review of the literature. During radiological follow‐up for prostate and colorectal cancer, an 82‐year‐old man was diagnosed with lung cancer with simultaneous mediastinal suspected neoplasm. Both were surgically removed with a single intervention performed via a uniportal video‐assisted thoracic surgery (uni‐VATS) approach. The literature emphasizes how extra‐thymic cancer can be diagnosed before, concurrently and consecutively with thymic neoplasia. The surgical treatment of such simultaneous cancer is challenging. We succeeded in the excision of both neoplasia with a mini‐invasive surgical technique. This report highlights the feasibility of uniportal VATS in a patient with very unusual clinical and oncological history.

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.

Mortality from extrathymic malignancy after thymic tumour resections: incidences and risk factors

OBJECTIVES

To identify risk factors associated with extrathymic malignancy-related mortality after thymic epithelial tumour resection.

METHODS

The Japanese Association for Research on the Thymus database registered the records of 2835 patients collected from 32 Japanese institutions from 1991 to 2010. The cumulative incidence function of death due to extrathymic malignancies or recurrence was calculated, with other causes of death as competing risks. Relevant risk factors associated with extrathymic malignancy-related deaths in patients with thymoma were evaluated using the Fine and Gray model.

RESULTS

In total, 2701 patients were eligible for the analysis (thymoma, 2374; thymic carcinoma, 273; thymic neuroendocrine tumour, 54). The median follow-up period was 4.6 years. The cumulative incidence function of death due to extrathymic malignancies at 10 years was 2.2% (3.2% due to recurrence) in patients with thymoma, 1.6% (38.6% due to recurrence) in patients with thymic carcinoma and 0% (36.6% due to recurrence) in patients with thymic neuroendocrine tumour. In the multivariable analysis, age (every 10 years) at thymectomy [hazard ratio (HR) 2.19, 95% confidence interval (CI) 1.53-3.14; P < 0.001], male gender (HR 2.62, 95% CI 1.19-5.77; P = 0.017) and previous malignancies (HR 3.09, 95% CI 1.18-8.11; P = 0.022) were significant factors for death due to extrathymic malignancies after thymectomy.

CONCLUSIONS

Continued management and early detection of extrathymic malignancies may improve survival of patients with thymoma who are male, of advanced age, or have previous malignancies. Prospective studies are required to further investigate the management of extrathymic malignancies.