Short summary

This project will investigate if ctDNA from pleural fluid can be used in the diagnostic evaluation in patients under suspicion of cancer with involement.

Rationale

Lung cancer is the leading cause of cancer deaths in Denmark, partly because lung cancer is often diagnosed in an advanced stage when curative treatment is not possible. Pleural effusion is a frequent condition with approximately 20,000 cases per year in Denmark, and thoracic malignancy is a common cause. However, many benign diseases such as pneumonia and heart failure can also lead to pleural effusion. The fluid can be analyzed for malignant cells thereby verifying a diagnosis of cancer, but cytology has a moderate level of sensitivity and depends on the histologic type and organ of origin. If pleural effusion is cancer-related, obtaining a diagnosis might be challenging and prolonged, requiring multiple imaging tests and potentially thoracoscopy. A marker for pleural malignancy with high sensitivity and specificity is desirable. Aberrant methylation occurs in almost all tumors, and analysis of aberrantly methylated tumor DNA has gained increasing interest. A number of studies have suggested its potential for early diagnosis and screening. Plasma is one of the most commonly used biological sample types, but organ-specific samples such as bronchial lavage fluid or pleural effusion might contain more tumor DNA. We have developed a multiplex panel of genes which are aberrantly methylated in lung cancer compared to DNA from normal cells. The panel includes the HOXA9 gene, which showed the ability to detect lung cancer with a sensitivity and specificity of 75% and 80%, respectively, in bronchial lavage fluid. The application of a multiplex panel may be able to increase the diagnostic accuracy compared to a single-gene marker in pleural effusion samples.

Description of the cohort

Patients with pleuraeffusion under investigation.

Data and biological material

Pleura fluid, data from patient journal (demographic, cancer diagnosis).

Collaborating researchers and departments

Department of Oncology, Vejle Hospital

• Sara Wen

Respiratory Department Zealand University Hospital

• Uffe Bødtger