Question

You are a junior doctor on your primary care rotation. You see Pascal, a man recently diagnosed with lung cancer. He wants to discuss a 'rash' that has been gradually arising in his axillae, and also now on his abdomen. While talking to him, you notice that he has moon facies and facial plethora.

To what type of lung cancer can these symptoms all be attributed?

Answer 1

Paraneoplastic syndrome, particularly Cushing's syndrome seen as moon facies and facial plethora, can be caused by small cell lung cancer, a condition that leads to ectopic production of ACTH and subsequent cortisol overproduction.

Step-by-step explanation:

The symptoms of moon facies, facial plethora, and a gradually arising rash in the axillae and abdomen can all be attributed to a condition known as paraneoplastic syndrome, which is associated with lung cancer. This syndrome occurs when cancer-fighting antibodies or other immune substances mistakenly attack normal cells in the body, leading to various symptoms, including skin rashes and changes in appearance. The presence of moon facies, in particular, is a classic sign of Cushing's syndrome, which can be a paraneoplastic phenomenon caused by small cell lung cancer (SCLC). SCLC can produce ectopic adrenocorticotropic hormone (ACTH), leading to an overproduction of cortisol and resulting in the characteristic features of Cushing's syndrome.