Introduction: Lung cancer is the fifth most common form of cancer in Sweden. Patients are often diagnosed in a late stage of the disease. Within radiology, often a conventional chest x-ray is performed first, and if positive (ie. suspicious for malignancy) a computer tomography (CT) examination is later performed in order to be able to accurately diagnose and measure tumor size. The patient may be involved in many different x-ray examinations, after being diagnosed with lung cancer and digital x-ray tomosynthesis (DTS) is one of them. DTS is a more sensitive examination method in comparison with conventional chest radiography. Objective: Our aim was to investigate whether DTS is diagnostically justifiable compared to a CT scan for measurement of tumor size in the lungs and see what possibilities and limitations DTS has. Method: We have written a literature review based on our questions and purpose, which includes ten articles that we have found in various databases. Results: Our results show that CT scan of the lungs is the best for assessment of lungcancer. DTS is superior to conventional two-view chest x-ray when it comes to measure tumor sizes. Conclusion: To assess tumor size of lung cancer by DTS is superior to conventional chest x-ray, but inferior to CT of the lungs.