Combining PETCT with a glutamate based blood test improves cancer diagnosis in solitary pulmonary nodules. (R-12282)

PET-CT is an indispensable technique in lung cancer staging, where almost no lung lesion goes undetected since its sensitivity reaches 96%. However, PET-CT often fails to discriminate between malignant and non-malignant PET-positive solitary pulmonary nodules (SPNs) with a specificity of only 23%. 40-50% of those patients are advised to repeat their CT after three to six months to follow up on their lesions' progression, delaying a clear and correct cancer diagnosis and subsequent therapy. In more than 10% of the patients with an SPN on the PET-CT scan, an uncertain lung cancer diagnosis based on the PET-positive lesion leads to surgery that appears to be unnecessary. This project aims to use the plasma glutamate concentration as a biomarker to complement PET-CT in the discrimination between malignant and non-malignant PET-positive SPNs. We will validate a plasma glutamate determination by high-performance liquid chromatography (HPLC) since this test needs to be rapid, cheap, minimally invasive, and available in every hospital. Together with the PET-CT's basic parameters, a quick measurement of fasted plasma glutamate levels right before undergoing a PET-CT scan will support a more rapid lung cancer diagnosis and treatment, resulting in less risk for disease progression. In conclusion, our approach will improve the accuracy of lung cancer diagnosis, and avoid unnecessary surgery.

Keywords:glutamate, lung cancer, PET-CT

Disciplines:Cancer diagnosis, Cancer biology, Cancer prevention, Cancer therapy