Standard Outcome Measures for Thymic Malignancies

Treatment updates in advanced thymoma and thymic carcinoma

OPINION STATEMENT

Thymomas and thymic carcinomas are rare diseases of the anterior mediastinum. Although some thymomas are quite indolent and able to be resected in a curative fashion, the treatment of metastatic disease remains a challenge, especially for the more aggressive thymic carcinoma histology. Based on the results of single-arm trials, combination chemotherapy is the standard of care in the first-line, and anthracycline-based treatments should be used if patients are reasonably fit. Several single-agent cytotoxic chemotherapy agents have some effectiveness in subsequent lines of therapy, especially pemetrexed and, in octreotide scan-positive patients, octreotide. Prospective trials of new agents are difficult to conduct given the rarity of thymoma, but various targeted therapies do show promise. Greater international research collaboration, as well as modern techniques in molecular and genomic characterization, should help to advance the treatment of thymic malignancies in the near future.

Preoperative CT findings of thymoma are correlated with postoperative Masaoka clinical stage

RATIONALE AND OBJECTIVES

Both preoperative computed tomography (CT) staging and postoperative surgical Masaoka clinical staging are of great clinical importance for diagnosing thymomas. Our study aimed to investigate the relationships between these two staging systems.

MATERIALS AND METHODS

This was a retrospective review of 129 patients who had undergone thymoma surgery. Helical CT and 16-slice CT were performed preoperatively. Surgical findings were evaluated according to the Masaoka clinical staging system.

RESULTS

A significant association was shown between Masaoka clinical staging and CT staging, especially of features including tumor size (P = .004), tumor shape (P < .001), tumor density (P < .001), capsule completeness (P < .001), and involvement of surrounding tissues (P < .001). Based on the CT findings, there were 35.09% of Masaoka stage I patients who had a tumor size <5 cm as compared to 14.81% of stage IV patients. Only 8.77% of Masaoka stage I patients had a tumor size ≥10 cm as compared to 40.74% of stage IV patients. In stages III and IV, most tumors were irregularly shaped with an uneven density and incomplete capsule. Invasive tumors were more frequently found in stages III (81.48%) and IV (88.89%) than in stages I (0%) and II (38.89%). The incidence of myasthenia gravis was comparable in different stages. Consistency between CT and Masaoka clinical stages was higher in stage I (37.98%) than other stages (approximately 10%).

CONCLUSION

This study documented a close relationship between preoperative CT thymoma staging and postoperative Masaoka clinical staging. Thus, preoperative CT findings can be beneficial for determining the proper management and prognosis of thymoma patients.

Thymectomy for thymoma and myasthenia gravis. A survey of current surgical practice in thymic disease amongst EACTS members

Thymic disorders, both oncological and non-oncological, are rare. Multi-institutional, randomized studies are currently not available. The Thymic Working Group of the European Association for Cardio-Thoracic Surgery (EACTS) decided to perform a survey aiming to estimate the extent and type of current surgical practice in thymic diseases. A questionnaire was addressed to the thoracic and cardio-thoracic members of the society, and the answers received from 114 participants were analysed. High-volume surgeons cooperate more frequently with a dedicated neurologist and anaesthesist (P = 0.04), determine more frequently neurological scores pre- and postoperatively (P = 0.02) and do not operate on thymic hyperplasia in stage I myasthenia gravis (MG) (P = 0.04). High-volume thymoma surgeons more often use a transpleural approach for stage I thymoma < 4 cm (P = 0.01), induction therapy (P = 0.05) and are more likely to have access to a tissue bank (P = 0.04). Both in thymoma and MG surgery, cooperative prospective studies seem to be feasible in dedicated thoracic surgical associations as EACTS.

Thymoma: from chemotherapy to targeted therapy

Thymic malignancies are rare epithelial tumors that may be aggressive and difficult to treat. Thymomas are frequently eligible for upfront surgical resection. However, nearly 30% of patients present with locally advanced tumor at time of diagnosis, and chemotherapy is then used to reduce the tumor burden-possibly allowing subsequent surgery and/or radiotherapy. Metastatic and recurrent thymic malignancies may be similarly treated with chemotherapy. More recently, the molecular characterization of thymoma led to the identification of potentially druggable targets, laying the foundation to implement personalized medicine for patients.