ReviewThymomas: Review of Current Clinical Practice
Section snippets
Classification of Thymomas
Several classification systems of thymomas have been developed and described. However, clinical, pathologic, and surgical classification of thymomas remains controversial. The histomorphologic variability and heterogeneity of cells within thymomas is a major factor guiding this intense debate [8, 9, 10, 11]. The most commonly used classification systems are summarized in Table 1.
In 1961, Bernatz and colleagues [12] described thymomas according to their dominant cell type: predominantly spindle
Methods
To determine the state of the art in thymoma therapy, prognostic factors, and outcome, we searched the PubMed database for “thymoma” (with 6,981 hits listed). Only abstracts published in English were considered, and clinical studies with a case load with greater than 100 patients (n > 100) were selected for complete review. As no large prospective studies have been conducted as yet, all reviewed studies were retrospective. Due to the lack of larger studies evaluating diagnostic methods and the
Patient Characteristics
Twenty-eight studies that include 5,487 patients overall diagnosed with thymoma were identified, reviewed, and analyzed. Within these studies, patients' median age ranged from 45 to 59.5 years with an average follow-up of 95.2 months.
Applying the Masaoka staging system, 36% of all study patients had a stage I thymoma, 26% were stage II, 22% were stage III, and 10% were stage IV. Applying the World Health Organization classification system, 8% were type A, 26% were type AB, 15% were type B1, 28%
Radiological Imaging
Currently, computed tomography is the first choice technique to characterize a mediastinal mass with regard to its anatomic dissemination and invasion of neighboring structures, as well as possible distant metastases. Chest roentgenograms show merely a nonspecific broadened mediastinum [31], as shown and represented in Figure 1. Applying computed tomography, thymomas can often be distinguished from benign mediastinal lesions or from lymphoma in the case of multiple mediastinal abnormalities [32
Surgery
As the only curative treatment, surgery remains the baseline attempt in thymoma therapy. Complete or partial median sternotomy with complete thymectomy is the operative approach of choice [22, 23, 26, 46, 47, 48, 49], as first described by Blalock in 1941 [50]. In advanced tumors, especially if the lung or pleural space is invaded, the extension of a sternotomy to a hemi-clamshell incision or a full clamshell incision can be suitable. Approaches like transcervical and video-assisted
Comment
In summary, the Masaoka staging system seems to be the current state of the art in thymoma diagnostics and therapy. Computed tomography is the diagnostic tool of choice to image the mediastinal lesion and its anatomical extent. For histopathologic diagnosis, especially if the lesion is invading the neighboring structures, a preoperative specimen acquisition by FNA or core biopsy should be considered, especially if neoadjuvant therapy is considered.
Median sternotomy is the surgical approach of
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2021, Annals of Medicine and SurgeryCitation Excerpt :Although the transthoracic biopsy indicated thymic hyperplasia, not thymoma, both are indications of surgical resection. The median sternotomy is the operative approach of choice to excise normal-sized thymomas [6], but there is no consensus in the medical literature on the best approach to remove giant thymomas that extend to the pleural cavities. Only a median sternotomy was used in a few cases [7,8], as the innominate vein was invaded.
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