Certified Respiratory Therapist Practice Exam

A PET scan is most useful in diagnosing which of the following diseases?

1. COPD

2. Bronchogenic carcinoma

3. Tuberculosis

4. Pneumonia

The correct answer is: Bronchogenic carcinoma

A PET scan, or positron emission tomography scan, is particularly useful in diagnosing bronchogenic carcinoma, which is a type of lung cancer originating in the bronchial tubes. The PET scan works by using a radioactive substance that highlights areas of increased metabolic activity, which is characteristic of cancerous cells. This allows for a more accurate identification of malignant tumors compared to conventional imaging techniques. In contrast, while other conditions listed, such as COPD (chronic obstructive pulmonary disease), tuberculosis, and pneumonia, have specific imaging techniques and diagnostic criteria, they do not generally present the same level of metabolic activity detectable by a PET scan. Instead, these conditions are often diagnosed using physical exams, chest X-rays, CT scans, or laboratory tests, which assess lung function and infection rather than the metabolic processes indicative of malignancy found in bronchogenic carcinoma. Therefore, the effectiveness of a PET scan in detecting hypermetabolic activity makes it a superior choice for diagnosing lung cancer.