Can a cavity in chest X-ray confirm the diagnosis of tuberculosis? The diagnosis of tuberculosis cannot be confirmed by a chest X-ray with a cavity. In addition to chest X-ray and chest CT, there are other tests such as PPD test, sputum to find tuberculosis bacteria, and even bronchoscopy and biopsy for diagnosis, not by chest X-ray alone. If a lung lesion is found on chest X-ray and a cavity is found in the lesion, it is not necessarily tuberculosis, but can also be seen in lung tumors, fungal infections of the lung, lung abscesses and other diseases, which need to be further judged in combination with clinical, or even other tests for further diagnosis.