From the Guidelines
Calcified mediastinal and hilar lymphadenopathy are distinct radiological findings that differ primarily in location, with mediastinal lymphadenopathy involving enlarged lymph nodes in the mediastinum and hilar lymphadenopathy affecting lymph nodes at the hilum of the lungs. The distinction between these two conditions is crucial for accurate diagnosis and management. According to the study by Munden et al 1, the size, texture, and distribution of the lymph nodes, as well as the presence of calcification, are important factors to consider when evaluating these conditions. The study suggests that a short-axis size threshold of 15 mm can guide the decision process, and that pulmonary findings and clinical history are also important in determining management. Calcification in lymph nodes typically indicates a chronic or healed inflammatory process, and common causes include granulomatous diseases such as tuberculosis, histoplasmosis, and sarcoidosis, as well as silicosis, coal worker's pneumoconiosis, and treated lymphoma 1. Some key points to consider when evaluating calcified mediastinal and hilar lymphadenopathy include:
- Location: Mediastinal lymphadenopathy involves the central compartment of the thoracic cavity, while hilar lymphadenopathy affects the hilum of the lungs.
- Size: A short-axis size threshold of 15 mm can guide the decision process.
- Texture and distribution: The presence of calcification, as well as the texture and distribution of the lymph nodes, are important factors to consider.
- Clinical history: A thorough clinical evaluation, including patient history and physical examination, is necessary to differentiate between these conditions.
- Additional testing: CT scans, PET scans, or tissue sampling may be recommended if malignancy is suspected or if symptoms develop. In terms of management, a thorough clinical evaluation and possibly additional testing such as CT scans, PET scans, or tissue sampling are necessary to differentiate between calcified mediastinal and hilar lymphadenopathy and to determine the underlying cause. While calcified lymph nodes often represent benign conditions, follow-up imaging may be recommended to ensure stability, particularly in patients with risk factors for malignancy or if symptoms develop 1.
From the Research
Distinction between Calcified Mediastinal and Hilar Lymphadenopathy
The distinction between calcified mediastinal and hilar lymphadenopathy can be understood by examining the causes and characteristics of each condition.
- Mediastinal lymphadenopathy refers to the enlargement of lymph nodes in the mediastinum, which can be caused by various benign and malignant conditions, including lung cancer, lymphoma, and granulomatous diseases such as sarcoidosis and tuberculosis 2.
- Hilar lymphadenopathy, on the other hand, refers to the enlargement of lymph nodes in the hilar region of the lungs, which can be caused by similar conditions, including sarcoidosis, tuberculosis, and malignancies 3.
Calcification in Lymphadenopathy
Calcification in lymphadenopathy can occur in both mediastinal and hilar lymph nodes, and is often associated with granulomatous diseases such as sarcoidosis 4, 5.
- A study found that hilar lymph node calcification was observed in 22.8% of patients with sarcoidosis, with punctate calcification detected in 15.4% of cases and diffuse calcification observed in 84.6% of cases 4.
- Another study reported a case of enlarging mediastinal/hilar lymphadenopathy with calcification, which was diagnosed as monoclonal gammopathy of undetermined significance (MGUS) associated with mediastinal amyloidosis using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) 5.
Diagnosis and Distinction
The diagnosis and distinction between calcified mediastinal and hilar lymphadenopathy can be made using various imaging modalities, including computed tomography (CT) and positron emission tomography (PET), as well as tissue diagnosis modalities such as EBUS-TBNA and transbronchial forceps biopsy 2, 6, 3.
- A study found that transbronchial forceps biopsy was safe and effective in diagnosing mediastinal lymphadenopathy, with a diagnostic yield of 100% in cases of sarcoidosis and 85.7% in cases of malignant lymph nodes 6.