Invasive methods for the diagnosis and management of intrathoracic extramedullary hematopoiesis: A literature review.

Background: Extramedullary hematopoiesis is defined as hematopoiesis occurring outside of the bone marrow. It usually compensates insufficient bone marrow function or ineffective erythropoiesis and is observed mostly in hematological disorders. Most common locations of extramedullary hematopoiesis are the spleen, the liver and the lymph nodes. Intrathoracic extramedullary hematopoiesis is rare presenting as bilateral lobulated masses of lower paravertebral regions. This review summarizes the role of invasive techniques in the diagnosis and management of intrathoracic EMH and its complications.

Methods: An electronic search in PubMed and Google Scholar was conducted with the keywords "intrathoracic extramedullary hematopoiesis" AND "surgery" OR "video-assisted thoracic surgery (VATS)" OR "medical thoracoscopy" OR "biopsy" OR "thoracotomy" OR "image-guided biopsy" OR "median sternotomy", within 1970 to 2020 with the limitation of English language to include those articles reporting data on invasive techniques in intrathoracic extramedullary hematopoiesis.

Results: Overall, 93 articles were originally identified using our search criteria and from the reference list of the previously identified documents. Following elimination of duplicates, 29 were excluded after title, abstract or full text screening, since they did not report the use of invasive techniques in the diagnosis and management of intrathoracic extramedullary hematopoiesis.

Conclusions: Although in some cases radiological features are typical for the diagnosis of intrathoracic extramedullary hematopoeisis, invasive methods such as bronchoscopy with transbronchial biopsy, ιmage-guided fine needle aspiration, endobronchial ultrasound-guided fine needle aspiration of the mass and mediastinoscopy, medical thoracoscopy, median sternotomy, video-assisted thoracoscopic surgery and thoracotomy, are essential for definite diagnosis and management.