Second malignancy versus recurrence after complete resection of thymoma

Incidence of second malignancies in patients with thymic carcinoma and thymic neuroendocrine tumor

OBJECTIVES

Thymic carcinoma and thymic neuroendocrine tumor (NET) are rare and are more likely to develop second malignancies. The purpose of this study was to explore the incidence and lifetime risk of second malignancies in thymic carcinoma and thymic NET.

METHODS

The standardized incidence ratio (SIR) and the age-adjusted cancer incidence of the thymic carcinoma and thymic NET patients with second malignancies were retrospectively calculated by using the Surveillance, Epidemiology, and End Results (SEER) database. Prognosis results were also determined by Kaplan-Meier analysis and Cox regression.

RESULTS

1130 patients with thymic carcinoma (73 patients had second malignancies) and 263 patients with thymic NET (19 patients had second malignancies) from 2000 to 2018 are included. Patients with thymic carcinoma (SIR: 1.36, 95% CI 1.08-1.69) and with thymic NET (SIR: 1.73, 95% CI 1.13-2.54) demonstrate an increased overall risk of developing second malignancies in various organ systems. The age-adjusted cancer incidence of second malignancies in patients with thymic carcinoma is 3058.48 per 100,000 persons (4178.46 per 100,000 persons in patients with thymic NET). Age at diagnosis is a significant risk factor for the development of second malignancies.

CONCLUSION

The incidence of second malignancies in patients with thymic carcinoma and thymic NET is significantly higher than the patients in the normal population. The occurrence of second malignancies is not related to the use of different treatments. It is important to extend the follow-up period and add other screening methods.

Simultaneous resection of coexisting pulmonary and mediastinal lesions by video-assisted thoracic surgery: a case-series study

BACKGROUND

With the growing number of patients with coexisting pulmonary and mediastinal lesions detected, reports about simultaneous video-assisted thoracic surgery (VATS) for these concurrent diseases are still rare. To further explore the safety and effectiveness of simultaneous resection of pulmonary and mediastinal lesions by uniportal or biportal VATS, we retrospectively analyzed the clinical data of the largest series of cases to date.

METHODS

From July 2018 to July 2021, all patients whose pulmonary lesions and mediastinal tumors were resected simultaneously in our institution were retrospectively reviewed. Their demographic and clinical data were collected and analyzed.

RESULTS

A total of 54 patients were enrolled, of whom 44 underwent unilateral uniportal VATS, 3 underwent bilateral uniportal VATS and 7 underwent unilateral biportal VATS. Seven cases were converted to thoracotomy during surgery. For the remaining 47 patients with various demographic and clinical characteristics, most of the operations were completed within 3 h (n = 33, 70.2%) with blood loss of no more than 100 mL (n = 43, 91.5%). The duration of chest tube drainage was 5.66 ± 3.34 days, and the average daily volume was 196.90 ± 122.31 mL. Four cases of postoperative complications occurred during hospitalization. The length of postoperative hospital stay was 8.60 ± 3.63 days. No severe complications or deaths were observed during follow-up.

CONCLUSIONS

Uniportal and biportal VATS are safe and effective for simultaneous resection of selected coexisting pulmonary and mediastinal lesions, but the indications and operational details need more evaluation.

Secondary Malignancy Risk Following Proton vs. X-ray Radiotherapy of Thymic Epithelial Tumors: A Comparative Modeling Study of Thoracic Organ-Specific Cancer Risk

Simple Summary

Proton beam radiotherapy (PBT) offers the possibility to significantly reduce dose to surrounding organs at risk due to their physical advantages compared to X-ray based techniques. The aim of this analysis was to demonstrate whether PBT reduces secondary malignancy risks in patients with thymic malignancies compared to 3D conformal and intensity-modulated radiotherapy with photons. By using two different mechanistic calculation models we could demonstrate significant reductions of secondary malignancy risks with the use of PBT for all independent thoracic organs analyzed with the exception of the thyroid gland. This technology-driven improvement might translate into clinically relevant benefits for patients with thymic malignancies.

Abstract

Background: Proton beam radiotherapy (PBT) offers physical dose advantages that might reduce the risk for secondary malignancies (SM). The aim of the current study is to calculate the risk for SM after X-ray-based 3D conformal (3DCRT) radiotherapy, intensity-modulated radiotherapy (IMRT), and active pencil beam scanned proton therapy (PBS) in patients treated for thymic malignancies. Methods: Comparative treatment plans for each of the different treatment modalities were generated for 17 patients. The risk for radiation-induced SM was estimated using two distinct prediction models—the Dasu and the Schneider model. Results: The total and fatal SM risks estimated using the Dasu model demonstrated significant reductions with the use of PBS relative to both 3DCRT and IMRT for all independent thoracic organs analyzed with the exception of the thyroid gland (p ≤ 0.001). SM rates per 10,000 patients per year per Gy evaluated using the Schneider model also resulted in significant reductions with the use of PBS relative to 3DCRT and IMRT for the lungs, breasts, and esophagus (p ≤ 0.001). Conclusions: PBS achieved superior sparing of relevant OARs compared to 3DCRT and IMRT, leading to a lower risk for radiation-induced SM. PBS should therefore be considered in patients diagnosed with thymic malignancies, particularly young female patients.

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.

Thymoma appearing 9 years after the resection of squamous cell carcinoma of the lip: A case report of triple primary tumors and literature review

The occurrence of second primary tumor (SPT)following malignancy treatment is common. In patients with head and neck (H&N) cancer, SPTs principally occur in the H&N region, lungs or esophagus. Therefore, patient follow-up after cancer treatment is important in order to detect recurrence, metastasis and new primary tumors. However, no standard guidelines on lifelong follow-up imaging are available. Herein, we report a patient who presented with three metachronous primary tumors-squamous cell carcinoma (SCC) of the tongue, SCC of the lip and type A thymoma. The third tumor was incidentally detected during follow-up using contrast-enhanced computed tomography (CT) 9 years following resection of the second tumor. To the best of our knowledge, this specific combination of metachronous tumors has not yet been reported. Based on the literature review, we observed that thymoma occurs following H&N cancer treatment. Therefore, to ensure that the presence of subsequent thymomas is not overlooked, we suggest regular lifelong follow-up using contrast-enhanced CT in patients who had previously been diagnosed with H&N cancer. The literature review revealed that thymomas occur in patients with H&N cancer and should be detected at the earliest convenience.

Low incidence of and mortality from a second malignancy after resection of thymic carcinoma†

OBJECTIVES

Previous studies have suggested that a second malignancy often develops after resection of thymoma; however, it remains unknown whether this is applicable to thymic carcinoma.

METHODS

A retrospective chart review was performed based on our multi-institutional database of resected thymic epithelial tumours between 1991 and 2016. A second malignancy was defined as newly diagnosed after thymic tumour resection. The cumulative incidence of and related death from a second malignancy after thymic and neuroendocrine carcinoma resections were estimated using a competing risk model and were compared to those of patients undergoing a thymoma resection.

RESULTS

Two hundred and thirty-eight patients were identified (thymic carcinoma 59; thymoma 179). A second malignancy developed in 1 patient (1.7%) with thymic carcinoma and in 17 patients (9.5%) with thymoma. Deaths from second malignancies were noted in 7 patients with thymoma. There was a tendency towards a lower cumulative incidence of and a lower cumulative death from a second malignancy after thymic carcinoma resection (P = 0.139 and P = 0.20, respectively) than after thymoma resection. The cumulative incidence of a second malignancy in patients with thymic carcinoma was 2.8% at 5 years and at 10 years (8.0% at 5 years and 11.8% at 10 years in patients with thymoma).

CONCLUSIONS

After resection of thymic and thymic neuroendocrine carcinoma, the probability of developing a second malignancy, as well as mortality from a second malignancy, is very low. A prospective study with a larger sample size is required to validate our results.