Basic and Clinical Sciences (BCSE) Practice Exam

Which organ is most likely to show asymptomatic extra thoracic metastases in lung cancer?

1. Kidney

2. Liver

3. Heart

4. Pancreas

The correct answer is: Liver

The liver is the organ most likely to show asymptomatic extra thoracic metastases in lung cancer. This is primarily due to the liver's rich blood supply and its anatomical position, which makes it a common site for hematogenous spread from lung malignancies. In many cases of lung cancer, metastases can develop in the liver without causing noticeable symptoms. This asymptomatic nature is particularly significant because patients may not exhibit any clinical signs until the disease has progressed. Late-stage liver metastases can lead to symptoms, but early detection through imaging studies may reveal liver involvement before symptoms arise. Other organs such as the kidney, heart, and pancreas can also be involved in metastatic disease; however, they do not have the same propensity for asymptomatic involvement in the context of lung cancer metastases. The liver tends to be the most frequently affected extra-thoracic site, which is why it is the best answer for this question.