With increasing use of chest CT, incidental mediastinal lymphadenopathy seems to be frequently discovered and subsequently biopsied using EBUS. The “if it’s enlarged, stick a needle in it” mantra is challenged by a paper by Stigt et al.
83 people (age ~59) with at least one incidentally discovered mediastinal lymph node > 1 cm were enrolled. None had an associated mass.
- In 43%, a CT-angiogram for suspected pulmonary embolus identified the incidental lymphadenopathy.
- Most (>50%) had at least 3 stations with lymph nodes > 10 mm.
- Most (77%) had hilar lymphadenopathy, too.
- PET was done in 29, and showed high uptake in mediastinal nodes in 25 (87%).
All got endoscopic ultrasound / endobronchial ultrasound with fine needle aspiration. 76 of the 83 had adequate samples. The main results:
- 55 reactive lymph nodes
- 18 granulomatous disease, likely sarcoidosis
- 1 non-TB mycobacterial infection
- 1 metastatic breast cancer – who had a history of breast cancer and a loculated (cytology-negative) pleural effusion
- No new diagnoses of cancer
Follow-up CTs (~4 months later) were available for 36 of the 62 patients deemed to have no final diagnosis from the biopsy:
- 24 of the 36 had unchanged lymphadenopathy.
- In 9, it went away.
- 2 had progressive lymphadenopathy. Further biopsies revealed metastatic lung cancer in both. Both initial EUS/EBUS biopsies were negative, with adequate samples. A harder look back at the original CT scans revealed … still no masses identifiable.
When it comes to staging known lung cancer, EBUS / EUS looks equal or superior to mediastinoscopy, and (if it becomes standard care) could prevent thousands of unnecessary mediastinoscopies and thoracotomies. See recent articles in JAMA and CHEST.