How to obtain adequate biopsy specımen in suspected thymic tumors

Abstract

Pathologic diagnosis of thymic tumors (TTs) can be made by surgical or nonsurgical procedures. About 20% of TTs had been diagnosed by pretreatment biopsy methods while the rest had gone to surgery for diagnosis and treatment. However, in the last two decades there was an increase in pretreatment procedures for optimal management of locally advanced or metastatic TTs. Pretreatment tissue diagnosis of a noninvasive TT is not a standard option but is required if there is suspect or atypical clinical presentation and imaging, an invasive tumor requiring a nonsurgical approach or preoperative chemotherapy or chemoradiotherapy, strong possibility of lymphoma or unclear differential diagnosis between lymphoma or other solid tumor by imaging studies, or suspicion of a metastatic lesion. In surgical diagnosis anterior mediastinotomy, video-assisted thoracic surgery or mediastinoscopy can be chosen for invasive TTs whereas total resection is performed for small, noninvasive tumors. Nonsurgical diagnosis can be made by transthoracic fine or core needle biopsies (TTFNA, TTCNB), conventional bronchoscopy, endobronchial ultrasonography-guided transbronchial needle aspiration (EBUS-TBNA), endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) or medical thoracoscopy depending on procedural amenability according to tumor extension. TTFNA and TTCNB have been the most frequently used nonsurgical methods. However, there is an upward trend in using conventional bronchoscopy, EBUS-TBNA, EUS-FNA and medical thoracoscopy recently. To increase the diagnostic performance of these procedures in TTs, recommendations are (I) obtaining histologic specimens, (II) combining smears or liquid based cytology preparations and cell blocks, (III) obtaining multiple sufficient samples, (IV) combining histologic and cytologic specimens, (V) performing morphologic, immunohistochemical and molecular analyses on all specimens, (VI) using rapid onsite evaluation for cytologic specimens, (VII) correlating pathologic, clinical and radiologic findings, (VIII) consulting experienced pathologists.

Effect of wet-heparinized suction on the quality of mediastinal solid tumor specimens obtained by endoscopic ultrasound-guided fine-needle aspiration: a retrospective study from a single center

“…It is generally believed that a larger sample volume performs better in final diagnosis. Bilaçeroğlu S et al [ 19 ] believed that sufficient sample volume is an important factor that facilitates diagnosis, since it can not only fulfill the criteria for a pathologic diagnosis but also be used for adjuvant examinations such as IHC staining [ 20 , 21 ]. Here, we selected a 19G needle for puncture, as a large-bore needle contributes to a higher positive rate and accuracy in diagnosis of mediastinal lesions and more ideal tissue specimens [ 22 – 25 ].…”

Giant thymoma presenting as a large bilateral intrathoracic mass: A case report and a comparison between median sternotomy and hemiclamshell approach

“…The differential diagnoses of a giant intrathoracic mass include sarcoma, solitary fibrous tumor, lymphoma, mesothelioma, and metastatic tumors. A Transthoracic core needle biopsy accurately differentiates thymic tumors from other intrathoracic masses and has high sensitivity and specificity (90–100%) [ 5 ]. Although the transthoracic biopsy indicated thymic hyperplasia, not thymoma, both are indications of surgical resection.…”