The aim of our study is to investigate if CK19 mRNA-detection via OSNA can accurately detect lymph node metastases in lung cancer patients using EBUS-TBNA samples.

Regional lymph nodes are assessed before tumor resection and before initiation of chemo- or radiotherapy. Endobronchial ultrasound-guided needle aspiration (EBUS-TBNA) is a well-established method for mediastinal and hilar lymph node staging [2, 3]. Samples obtained via this route are much smaller than surgical lymph node biopsies, yet they are able to provide complete and thorough evaluation, this includes current molecular testing.

One Step Nucleic Acid Amplification (OSNA), a molecular test that utilizes CK 19 mRNA-concentration as a target marker is becoming a rapidly dynamic method in quick detection of sentinel lymph node (SLN) metastases in breast cancer, colon cancer and other cancers.

In lung cancer, the role of SLN is not well established. However, recent publications suggest an accurate and rapid detection of lymph node metastases in NSCLC. However this requires complete lymph node dissection either with mediastinoscopy or by other surgical means such as thoracotomy.

The aim of our study is to investigate if CK19 mRNA-detection via OSNA can accurately detect lymph node metastases in lung cancer patients using EBUS-TBNA samples.

Inclusion Criteria:

• CT-scan suspicious for lung cancer,
• enlarged mediastinal lymph nodes (>10 mm),
• EBUS-TBNA to be performed,
• age: 18-99 years

Exclusion Criteria:

• age: <18 years

Patients with CT-scans suspicious for primary diagnosis of lung cancer and enlarged mediastinal lymph nodes Patients with known diagnosis of lung cancer and newly enlarged mediastinal lymph nodes