American Board of Internal Medicine (ABIM) Certification Practice Exam

For stage I non-small cell lung cancer, what size must the solitary tumor be?

1. Less than 3 cm

2. Between 3 cm and 5 cm

3. Greater than 5 cm

4. Any size

The correct answer is: Less than 3 cm

Stage I non-small cell lung cancer (NSCLC) is defined by the presence of a solitary tumor that has not spread beyond the lung or to lymph nodes. For a tumor to be classified specifically as stage I, it needs to be relatively small and confined. The threshold for size in determining the classification is crucial. A solitary tumor that is less than 3 cm indicates a lower stage of cancer where the disease is still localized. This is significant because smaller tumors are typically associated with a better prognosis, and the treatment options may be less invasive, including surgical resection. A tumor greater than this size may indicate progression to a higher stage, either due to size alone or due to other factors such as nodal involvement or metastasis. Overall, the classification criteria based on tumor size in stage I NSCLC emphasize the importance of early detection, where smaller tumors generally present a greater opportunity for successful treatment outcomes. Understanding this distinction helps in the effective management and treatment planning for patients with lung cancer.